2019/09/10 City Council Resolution 2019-116 RESOLUTION NO. 2019-116
A RESOLUTION OF CITY COUNCIL OF THE CITY OF ROHNERT PARK
AMENDING THE CITY OF ROHNERT PARK GENERAL PLAN CHAPTER 7
SECTION 7.5 "EMERGENCY MANAGEMENT" TO INCORPORATE THE CITY OF
ROHNERT PARK—2018 LOCAL HAZARD MITIGATION PLAN BY REFERENCE
INTO THE HEALTH AND SAFETY ELEMENT AND ADOPTING THE LOCAL
HAZARD MITIGATION PLAN
WHEREAS,the City of Rohnert Park is mandated by the State of California to maintain
an adequate and proper General Plan; and
WHEREAS, because of that mandate, the City of Rohnert Park's General Plan and the
various elements thereof must be continually updated with current data, recommendations and
policies; and
WHEREAS, Rohnert Park is vulnerable to natural hazards that may result in loss of life
and property, economic hardship, and threats to public health and safety; and
WHEREAS, Assembly Bill 2140 provides that the State of California will not exceed 75
percent of total state eligible costs for disaster relief unless the city has adopted a local hazard
mitigation plan in accordance with the Federal Disaster Mitigation Act of 2000 as part of the
safety element of its General Plan adopted pursuant to California Government Code §65302.6;
and
WHEREAS,the City of Rohnert Park Local Hazard Mitigation Plan(LHMP)has been
developed by the Rohnert Park Department of Development Services in cooperation with the
Department of Public Safety and other City departments with input from local, regional, state and
federal agencies; and
WHEREAS,the Federal Emergency Management Agency (FEMA) has further reviewed
the changes made in response to California Office of Emergency Services (Ca1OES) comments
and determined that the City of Rohnert Park Local Hazard Mitigation Plan is eligible for final
approval pending amendment into the General Plan; and
WHEREAS, on July 11, 2019,the Planning Commission held a duly noticed public
hearing at which time interested persons had an opportunity to testify either in support or
opposition to the proposal and the Planning Commission recommended that the City Council
approve the changes to the LHMP and amendments to the text of the General Plan; and
WHEREAS, on September 10, 2019, the City Council held a duly noticed public hearing
at which time interested persons had an opportunity to testify either in support or opposition to
the proposal; and
WHEREAS,the City Council has reviewed and considered the information contained in
the General Plan Amendment application for the proposal.
NOW, THEREFORE, BE IT RESOLVED,that the City Council of the City of
Rohnert Park makes the following findings and determinations with respect to the proposed
General Plan Amendment and City of Rohnert Park Local Hazard Mitigation Plan:
Section 1. The above recitations are true and correct.
Section 2. Environmental Review:
A. This project does not have the potential to cause a significant effect on the
environment. As a planning document it does not result in any development activity
that could impact the environment. The plan identifies ways to mitigate hazards
which will have a positive impact on the environment when implemented..
Therefore, it can be seen with certainty that there is no possibility that project may
have a significant effect on the environment, and the project is exempt from
environmental review pursuant to the "General Rule" exemption in CEQA Guidelines
Section 15061(b)(3).
Section 3. Findings related to the General Plan Amendments, including the Local Hazard
Mitigation Plan. The City Council makes the following findings concerning the General
Plan Amendments proposed by Planning Application No. PLGP19-0003:
1. The proposed General Plan Amendment would be consistent with specific policies in
the in the Health and Safety Element.
Criteria Satisfied. The proposed amendments are consistent with specific policies, as
amended, in the Health and Safety Elements of the General Plan applicable to the
Emergency Management section. The policies establish guidelines for emergency
preparedness and ensuring future protection of the City from hazards. The LHMP sets
forth concrete actions that are consistent with those policies regarding emergency
management.
2. A duly noticed public hearing has been held to receive and consider public testimony
regarding the proposed General Plan Amendment.
Criteria Satisfied. A duly noticed public hearing on the proposed General Plan
amendment was held on September 10, 2019.
3. The proposed General Plan Amendment is consistent with the General Plan.
Criteria Satisfied. The Health and Safety title of the General Plan calls for the
adoption of a LHMP. These goals and policies within the LHMP were drawn directly
from the City's General Plan. These goals shape future actions taken by the City and
community to reduce risk and minimize losses from natural disasters. To ensure
implementation of the LHMP is completed as planned,the goals serve as checkpoints
that responsible departments can use to check progress of mitigation action items. The
proposed amendments implement the General Plan and also identify a web page link
where the full copy of the LHMP can be found.
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4. The General Plan Amendments will not cause the General Plan to become internally
inconsistent
Criteria Satisfied. The General Plan Amendment provides documentation of and
incorporates the LHMP. The amendment serves to further implement the General
Plan goals and policies. The LHMP will work in conjunction with the General Plan
and has been created as an addition to the General Plan.
Section 4. The City Council hereby adopts General Plan Amendment PLGP 19-0003,
amending City of Rohnert Park General Plan Chapter 7 Section 7.5 "Emergency Management"
as shown in Exhibit A attached hereto,to incorporate the City of Rohnert Park—2018 Local
Hazard Mitigation Plan, and adopts the City of Rohnert Park—2018 Local Hazard Mitigation
Plan, incorporated by reference in the General Plan and attached hereto.
DULY AND REGULARLY ADOPTED on this 10th day of September, 2019 by the
City of Rohnert Park City Council by the following vote:
CITY OF ROHNERT PARK
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ATTEST:
JoAnne M. Buergler, City Cler
Attachment: Exhibit A
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Resolution 2019-116
3
7-1
7 Health and Safety
State law requires that the Health and Safety Element address the protection of the community from
risks posed by environmental hazards. These include effects of seismically induced surface rupture,
ground shaking, and ground failure, geologic hazards including landslides and subsidence,
flooding, and hazardous materials and waste. The Health and Safety Element addresses these topics
as well as emergency preparedness and management.
Exhibit A to Resolution
Rohnert Park General Plan
7-2
7.1 SEISMIC AND GEOLOGIC HAZARDS
GEOLOGY AND SOILS
Rohnert Park is located in the Santa Rosa-Petaluma Valley where the underlying geologic structure
is characterized by sediments deposited by streams on floodplains, alluvial deposits, and basins.
This geologic structure is depicted in Figure 7.1-1. Overall, general geologic conditions, slopes,
and soils do not vary significantly from one part of the city to another.
The geologic formations in Rohnert Park range in age from Jurassic to Holocene. The Franciscan
Complex of Jurassic-Cretaceous age is the oldest geologic unit and constitutes the basement rock
in the vicinity. The Franciscan Complex consists of a chaotic mixture of deformed sedimentary,
igneous, and metamorphic rocks. Although at a great depth beneath Cotati valley, the Franciscan
is exposed in the surrounding highlands. During the late Tertiary age, marine sediments and
volcanic rocks were deposited over a large area of the Franciscan Complex. Sedimentary rocks of
the Petaluma formation and volcanic rocks of the Sonoma group underlie the valley alluvium and
are exposed in the hills to the east. Several hundred feet of alluvial sediments of Quaternary age
have been deposited in the Cotati Valley by streams draining the surrounding highland area 1.
Soils within the city are almost entirely Clear Lake clays, as shown in Figure 7.1-2. The soils,
typical of poorly drained basins and floodplains, were formed from alluvial sediments derived from
the surrounding highlands. Clear Lake clays typically have low permeability, slow runoff
characteristics, low erosion potential, high shrink-swell potential, and may be corrosive to uncoated
steel products 2.
SEISMIC HAZARDS
There are no known active faults within Rohnert Park. The Healdsburg-Rodgers Creek fault zone
lies about five miles to the east of the city. The San Andreas Fault System is located approximately
15 miles west of the city. During the 1989 Loma Prieta Earthquake, Rohnert Park experienced
sustained shaking lasting 15 seconds and little damage. Secondary seismic hazards that could affect
Rohnert Park include ground-shaking, liquefaction, and ground settlement. Since virtually all
construction in Rohnert Park occurred after the incorporation of earthquake safety design in
California construction, there are no known structures in Rohnert Park that would be specifically
hazardous during an earthquake, such as unreinforced masonry buildings. The City’s Emergency
Management Plan is discussed in Section 7.5.
1 Herzog Associates, Preliminary Geologic and Soil Evaluation, New Civic Center, Rohnert Park, CA, 1989
2 USDA, 1972
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Figure 7.1-1: Geology
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Elevations range between 230 feet above mean sea level northeast of the city to 90 feet above mean
sea level on the western boundary of the city. Slope gradients are generally less than one-half
percent in the western portions of the city and about one percent in the eastern portions. Elevations
range between 230 feet above mean sea level northeast of the city to 90 feet above mean sea level
on the western boundary of the city. Slope gradients are generally less than one-half percent in the
western portions of the city and about one percent in the eastern portions. Maximum slopes of five
to eight percent exist northeast of the city along the bend in Petaluma Hill Road at the foot of the
Taylor Mountain. The area within the Urban Growth Boundary (UGB) is relatively flat and the
potential for landslides is low. The area outside the UGB but within the Planning Area slopes
eastward to the ridge of Sonoma Mountain, approximately 2,300 feet in height.
LANDSLIDE AND LIQUEFACTION HAZARDS
Given the relatively flat topography and the nature of soils, there is little risk of mudslides,
landslides, or erosion in the immediate Rohnert Park area. Soil liquefaction has the potential to
impact the Rohnert Park area during a significant earthquake. Liquefaction occurs when soils lose
their bearing capacity during a seismic event. The potential for liquefaction depends on the type of
soil and the extent that the soils are saturated with ground water. Soils underlying almost the entire
area within the city exhibit moderate susceptibility to liquefaction. Liquefaction susceptibility is
shown on Figure 7.1-2.
The seasonal expansion and contraction of Clear Lake clays can cause gradual cracking, differential
settling, and weakening of structures and roadways. Perhaps the most visible example of the effects
of Clear Lake clays is the cracked driveways and foundations in older sections of Rohnert Park.
GOALS: SEISMIC AND GEOLOGIC HAZARDS
HS-A Minimize the risk to life and property from seismic and geologic hazards in Rohnert Park.
POLICIES: SEISMIC AND GEOLOGIC HAZARDS
HS-1 Require new construction to utilize site preparation, grading, and foundation designs in
accordance with site specific soil conditions. Require submittal of a preliminary soils
report, prepared by a registered civil engineer.
Development should undertake necessary studies and structural precautions to prevent
structural damage due to soil expansion and contraction. The existing Subdivision
regulations require submission of a soils report. For areas in the city that have a moderate
or high liquefaction potential, information is available in the California Division of Mines
and Geology Special Publication 117, Guidelines for Evaluating and Mitigating Seismic
Hazards in California.
HS-2 Continue requiring all new buildings in the city to be built under the seismic requirements
of the Uniform Building Code and Uniform Plumbing Code.
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The City has adopted the Uniform Building Code and the Uniform Plumbing Code, which
mandates earthquake resistant building construction design standards. The City has
amended these codes, in part, to address soil conditions. The amendments require added
reinforcement of slabs and slab floors, protection of slabs from ground water, use of non-
expansive fill for building pads and beneath footings, and non-corrosive water piping
material underground.
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Figure 7.1-2: Liquefaction Susceptibility
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7.2 DRAINAGE, EROSION, STORMWATER, AND FLOODING
DRAINAGE
Creeks that drain the mountainsides flow into drainage channels that transverse Rohnert Park
generally from east to west. Excluding a small area near East Railroad Avenue, the city drains
westerly to the Laguna de Santa Rosa Creek. The area near East Railroad Avenue drains south to
Lichau Creek, which flows into the Petaluma River.
Gravel and silt may wash from the slopes into these drainage channels. In recent years, gravel and
silt were deposited in an enclosed stormwater drain underneath Goldridge Elementary School and
Golis Park. The materials reduced the capacity of the stormwater drain resulting in localized street
flooding. The problem has been addressed by annual clearing of the stormwater drain. The Sonoma
County Water Agency (SCWA) installed a siltation basin east of Petaluma Hill Road to intercept
the gravel and silt. The city’s drainage and 100- and 500-year flood zones are shown in Figure 7.2-
1.
Mud and Debris Flows
Mud and debris flows originate in hillside areas having deep topsoil with poor drainage
characteristics. Sloped hillsides, which may be the source of mud and debris flows, are located
approximately a mile east of Petaluma Hill Road. Given the topography, such mud and debris flows
would be channeled into drainage ways that generally flow east to west within the Rohnert Park
area. The SCWA regularly removes gravel and silt from these channels to maintain their ability to
adequately handle stormwater flows.
EROSION
As shown in Figure 7.2-1, erosion potential is low for almost all soils in the city, according to US
Soil Conservation Service ratings. This low potential is primarily related to high soil stability since
the slopes in the city are generally less than 2 percent. Erosion is presumably higher for soils in the
vicinity of creeks, as well as for loam soils and ponded clay soils. Instances of significant erosion
are most likely during construction. The formation of embankments or uneven topography, the
effects of machinery, and the removal of vegetation, can contribute to increased rates of erosion.
STORMWATER
Rohnert Park’s storm drainage is under joint management of the City and the SCWA. The City
maintains responsibility for the system of underground pipes that provides for minor and
intermediate drainage, while SCWA maintains the system of open channels that diverts major
drainage flows west towards the Laguna de Santa Rosa. Both the open channels and pipe systems
are designed to meet SCWA standards and comply with the National Flood Hazard Insurance
Program.
Amendments to the Clean Water Act established a two-phased approach to addressing storm water
discharges. Phase I, which is currently being implemented, requires National Pollutant Discharge
Elimination System (NPDES) permits for separate storm water systems serving large- and medium-
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7-8
sized communities (those with over 50,000 inhabitants), and for storm water discharges associated
with industrial and construction activity involving at least five acres. Buildout of this General Plan
is expected to increase Rohnert Park’s population to about 50,000.
Phase II, which is currently under development by the US Environmental Protection Agency
(EPA), will address remaining storm water discharges, including urban areas with populations
under 50,000, smaller construction sites, and retail, commercial, and residential activities. NPDES
requirements and regulations are expected to be similar for all cities with populations greater than
10,000.
As shown in Figure 7.2-2, there are a few isolated areas within the 1999 City Limits that are located
within the 100-year flood zone. Approximately 60 acres of land designated for future development
in the eastside is located in the 100-year flood zone, primarily along Copeland Creek and the
Hinebaugh Flood Control Channel. A small portion of land within the Wilfred-Dowdell Specific
Plan Area in the westside is located in the 500-year flood zone.
The City enforces flood control standards within 100-year flood hazard areas in accord with the
requirements of the National Flood Hazard Insurance Program. In addition to 100-year flood hazard
areas, localized, relatively minor flooding has occurred within Rohnert Park in recent years.
Natural flooding results from major rainstorms that cause overflows of stream courses, and may be
aggravated by inadequacies in local storm drain facilities. Flooding may occur in two ways:
• Stormwater may overflow the banks of drainage ways because the water flow exceeds the
channel capacity; or
• Stormwater may back up and collect in a low area because it cannot flow into a receiving
drainage channel.
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Figure 7.2-1: Soil Types and Erosion Potential
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Figure 7.2-2: Drainage and Flood Zones
Chapter 7: Health and Safety
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One area that experienced street flooding prior to 1999 was in the “G” Section neighborhood.
Gravel and silt partially filled and reduced the capacity of an underground storm water drain.
During a subsequent storm, storm water backed up street drains. The storm drain has since been
cleared of gravel and silt. The SCWA installed a siltation basin to intercept gravel and silt east of
Petaluma Hill Road.
Localized flooding also occurred in the “F” Section. In this instance, storm water backed up into
low lying streets, the North Rohnert Park Municipal Golf Course, and adjacent parcels because
storm water was unable to flow into the Bellevue-Wilfred Channel and the Laguna de Santa Rosa.
Another area of local flooding in 1999 included portions of the Rancho Verde Mobile Home Park,
parts of Martin Avenue, and adjacent commercial/industrial parcels. In this instance storm water
backed up and was unable to flow into the Labath Channel. As the rain tapered off and the level of
the Laguna de Santa Rosa fell, storm water drained from the flooded areas.
Silt deposited over the years in the Bellevue-Wilfred, Laguna de Santa Rosa, and Labath Flood
Control Channels has reduced the capacity of these channels, which has contributed to the flooding
problems. The SCWA widened both the Bellevue-Wilfred Flood Control Channel and the Laguna
de Santa Rosa and plans to remove accumulated silt in the near future.
SCWA Capital Projects Plan
Rohnert Park participates in the planning and development of drainage and flood control activities
within the Laguna-Mark West Zone 1A, administered by SCWA. In March 1998, SCWA circulated
a revised Capital Projects Plan for Fiscal Year 1999 to Fiscal Year 2003. Projects in the Capital
Projects Plan include improvements for the County’s seven designated flood control zones.
The Capital Projects Plan identifies 17 projects for funding in Zone 1A. Projects were identified by
an Advisory Committee for the Flood Control Zone, appointed by the SCWA’s Board of Directors.
Information and criteria used for selecting projects include historical flooding problems, areas
benefited, alternative funding available, special safety and health factors, coordination with other
public projects, and environmental concerns. Several of the projects will directly help improve
potential flooding problems in the Rohnert Park area. All projects are scheduled for completion by
the end of Fiscal Year 2000.
GOALS: DRAINAGE, EROSION, STORMWATER, AND FLOODING
HS-B Minimize the risk to life and property from flooding.
HS-C Control erosion and sedimentation to provide flood protection and protect water quality.
POLICIES: DRAINAGE, EROSION, STORMWATER, AND FLOODING
HS-3 Prepare and implement a Storm Water Management Plan to ensure protection of the surface
and groundwater resources.
The Storm Water Management Plan should include requirements for periodic monitoring
of storm water outfalls, public outreach and education, and the implementation of Best
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Management Practices (BMPs) for a variety of industrial, construction, and municipal
activities. Until such time that a Storm Water Management Plan is prepared, the City
should use existing regulations pertaining to subdivision design, zoning, building, and
grading ordinances and policies to reduce discharge of non-point source pollutants into
local streams.
HS-3A Work with the County to ensure that any new development east of Petaluma Hill Road
does not interfere with groundwater recharge.
HS-4 Ensure that the City’s regulations pertaining to subdivision design, zoning, building, and
grading ordinances and policies continue to include measures to minimize erosion and
sedimentation.
Policy EC-13 in Chapter 6: Conservation establishes creek protection zones and standards
to protect the city’s creeks.
HS-5 As part of the building permit process, require all development projects to comply with
hydrology and drainage policies incorporated in the applicable Specific Plans. Require the
project proponent to design and construct a storm drain system in accordance with the
SCWA Flood Control Design Criteria (latest revision), specific to the project. Encourage
the use of environmentally sensitive drainage improvements including flow reduction and
flood bypass systems in order to ensure protection of surface water quality and stream
integrity.
Policy LU-10A stipulates that all specific plans shall address hydrology and drainage for
their respective areas, as well as practices to be incorporated as part of individual
development projects.
The storm drain system may include:
• Street and underground storm drain improvements; and
• New underground storm drainage facilities.
The City should recommend the use of high infiltration measures to reduce stormwater
discharge into the regional storm drain system. Measures to divert surface runoff into open
areas that have high infiltration capabilities could include ponds built into landscapes,
unlined runoff channels, and dispersion points into landscaped areas. Where possible and
technically feasible, roof tops and paved areas should drain into underground dispersal
pipes or vegetated percolation beds. Landscaping in parking lots and around building
perimeters should be maximized.
The City shall review and approve the proposed drainage system requirements prior to
construction on the project site.
HS-6 As part of the building permit process, require new development greater than five acres in
size to prepare and implement a site-specific storm water pollution prevention plan
(SWPPP) that effectively reduces discharges of stormwater containing sediment and other
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pollutants resulting from site construction activities. In addition, require all projects,
regardless of size, to comply with any other stormwater provisions of the specific plans for
their respective areas.
Policy LU-10A stipulates that all specific plans shall address storm-water pollution for
their respective areas, as well as practices to be incorporated as part of individual
development projects.
The proponent shall comply with all requirements set forth in the State Water Resources
Control Board (SWRCB) General Construction Activity Storm Water Permit. SWRCB
requires site owners of development projects with construction activity resulting in soil
disturbance of an area greater than five acres to comply with the California General
Permit to Discharge Storm Water Associated with Construction Activity (NPDES General
Permit CAS000002). The Permit requires development and implementation of a SWPPP
emphasizing BMPs. The RWRCB maintains a list of suggested BMPs, which are schedules
of activities, prohibitions of practices, maintenance procedures, and other management
procedures to prevent or reduce pollution.
Policy EC-19 requires site preparation, grading, and foundation designs for erosion
control to prevent sedimentation and contamination of creeks.
Policy EC-21 establishes development standards for new construction adjacent to riparian
zones to reduce sedimentation and flooding.
HS-7 Prepare engineering studies when necessary to update drainage and flood zone maps and,
during rainstorms, conduct surveys and document locations of flooding.
HS-8 Systematically conduct maintenance, make repairs, or improve drainage facilities to
minimize localized flooding during rainstorms. Provide treatment to first-flush runoff
flows, street sweeping programs, and additional source controls to minimize non-point
source pollution.
Maintenance should occur more frequently during the winter.
HS-9 Use the City’s development review process to ensure that proposed development located
in 100-year flood zones undertakes measures to provide adequate protection from flood
hazards.
HS-10 Continue to use the National Flood Insurance Program standards and regulations as
guidelines for implementation of flood damage control programs in Rohnert Park. Work
with Federal Emergency Management Agency to update the 1991 Flood Insurance Rate
Maps to reflect improvements to Copeland Creek.
HS-11 In cooperation with the Sonoma County Water Agency, maintain flood plain areas,
drainage channels, and other drainage structures and improve drainage channel capacity in
ways that will preserve the natural character of habitat areas, riparian corridors, and
waterways to the maximum extent feasible.
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(Rev. 10/02)
Chapter 7: Health and Safety
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7.3 SOLID WASTE MANAGEMENT AND RECYCLING
The City is responsible for waste collections and diversion within the incorporated limits. Solid
waste disposal facilities are owned and operated by the Sonoma County Department of
Transportation and Public Works, which also helps maintain the County Integrated Waste
Management Plan (CoIWMP) jointly with the Sonoma County Waste Management Agency
(SCWMA).
The California Waste Management Act, passed in 1989, required cities to prepare solid waste
management planning documents that demonstrate how they would reduce the amount of waste
sent to landfills by 25 percent by 1995 and 50 percent by the year 2000. These planning documents
are known as the Source Reduction and Recycling Element (SRRE) and Household Hazardous
Waste Element (HHWE). The SRRE includes four main components: source reduction, recycling,
composting, and special waste. Each component identifies existing diversion programs and
examines, evaluates, and selects future diversion programs. Hazardous waste is discussed in
Section 7.4.
Rohnert Park’s SRRE and HHWE, both adopted in 1992, were incorporated into the 1994
CoIWMP, which consolidates the SRREs and HHWEs prepared by each jurisdiction in Sonoma
County. The CoIWMP, which includes a Facility Siting Element, is required to demonstrate the
county’s long-term ability to ensure the implementation of countywide diversion programs and to
provide adequate disposal for local jurisdictions through the siting of disposal and transformation
facilities.
SOLID WASTE
In 1995, Rohnert Park achieved a diversion or source reduction rate of 39 percent, which was 14
percent higher than the 1995 statewide diversion goal. However, in 1997, this rate fell to 38 percent,
which is 6 percent higher than the estimated state diversion rate. Some of this success was due to
the County’s comprehensive approach to waste reduction. Diversion goals are met through a
combination of local and countywide source reduction, recycling, and composting programs. In
adopting this approach, Rohnert Park has agreed in concept to sponsor or develop jointly some
programs and facilities with neighboring communities or with the County.
COLLECTION AND RECYCLING
Municipal solid waste is transported to the Central Disposal Site owned and operated by Sonoma
County Public Works Department. The site is located approximately five miles southwest of the
city in unincorporated Sonoma County. The City does not currently hold a disposal contract directly
with the landfill, but contracts for collection and disposal services with private haulers. In 1997,
Rohnert Park disposed of 50,528 tons of solid waste (see Table 7.3-1). Of the solid waste generated,
51 percent was used for fuel, 25 percent was recycled, 12 percent was landfilled, eight percent was
incinerated, and four percent was treated. Over 4,000 tons of recyclables were collected through
residential curbside and commercial collection. Furthermore, over 5,000 tons of yard debris and
wood waste was composted.
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Table 7.3-1:
Rohnert Park Solid Waste, 1997 Total Waste Generated 50,528 tons % Used for Fuel 51% % Recycled 25% % Landfilled 12% % Incinerated 8% % Treated 4%
Source: Integrated Waste Management Report Card, 1997.
The City contracts out to Empire Waste Management for refuse hauling and curbside recycling
services for single-family residents. Although there are no buy-back centers in Rohnert Park, two
are located north of the city. Commercial recycling includes cardboard, glass, newspaper, and office
paper collection. Approximately 2,951 tons of materials were collection through residential
curbside collection and 1,070 tons through commercial collection.
The SCWMA sponsors several other waste reduction efforts including the Eco-Desk hotline, the
annual Sonoma County Recycling Guide, the SonoMax waste exchange, master gardener home
composting workshops, the Recycling Market Development Zone, and Household Toxics
Roundups. The regional approach of the SCWMA has helped Sonoma County reduce solid waste
at the lowest possible cost.
Expansion of Solid Waste Disposal Facilities
Given current capacity and projected diversion rates, the Central Landfill is expected to reach
capacity in approximately 2005. The expansion of the Central Landfill was recently approved by
the County, allowing for disposal of solid waste up to 2010.
GOALS: SOLID WASTE MANAGEMENT AND RECYCLING
HS-D Reduce the generation of solid waste and recycle those materials that are used, to slow the
filling of local and regional landfills, in accord with the California Integrated Waste
Management Act of 1989.
POLICIES: SOLID WASTE MANAGEMENT AND RECYCLING
HS-12 Continue to work toward reducing solid waste and increasing recycling, in compliance with
the Sonoma County Integrated Waste Management Plan.
Rohnert Park has a responsibility to meet regional source reduction and recycling
initiatives in order to achieve State-mandated waste reduction targets and extend the useful
life of existing landfill facilities.
HS-13 As part of development review and environmental analysis, ensure that new multifamily
residential and all non-residential development comply with the City’s Source Reduction
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and Recycling Element (SRRE) and Household Hazardous Waste Element (HHWE), as
well as the Sonoma County Integrated Waste Management Plan (CoIWMP).
Multifamily residential development includes any residential structures with two or more
dwelling units.
HS-14 As part of the City’s Capital Improvement Program (CIP), the Parks, Recreation, and Open
Space (PROS) Master Plan, and other programs, explore the feasibility of installing
recycling receptacles for plastic and glass beverage containers and papers in parks and
other public areas (for example, community recreational facilities, transit stops, and mixed-
use districts).
The City and SCWA should consider other recycling strategies, including expanding
recycling collection at commercial and multifamily housing.
HS-15 Require new multifamily residential and all non-residential development to incorporate
attractive and convenient interior and exterior storage areas for recyclables into new or
remodeled buildings, to make recycling activities more convenient for those who use the
buildings.
Existing commercial businesses and business parks should be encouraged to install
recycling receptacles on their premises. Multifamily residential development includes any
residential structures with two or more dwelling units.
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7.4 HAZARDOUS MATERIALS
Hazardous materials include a large number of substances that may be dangerous to the public if
improperly stored, handled, or disposed. These include toxic metals, chemicals, and gases;
flammable and/or explosive liquids and solids; corrosive materials; infectious substances; and
radioactive material. Hazardous materials, according to the State Health and Safety Code §
25501(o), “include, but are not limited to, hazardous substances, hazardous waste, and any material
which a handler or the administering agency has a reasonable basis for believing that it would be
injurious to the health and safety of persons or harmful to the environment if released into the
workplace or the environment.”
WASTE MANAGEMENT AGENCY
In accordance with local Households Hazardous Waste Elements (HHWE) and the CoIWMP, the
Sonoma County Waste Management Agency (SCWMA) conducts a range of hazardous waste
programs. SCWMA conducts hazardous waste collection events at sites throughout Sonoma
County. Over ten events are held each year, generally during dry weather months. At least one
event is held in Rohnert Park. Rohnert Park businesses and residents may dispose of hazardous
waste at any event in the County. Hazardous materials collected are packaged and taken to disposal
sites outside Sonoma County.
The Agency plans to establish a permanent hazardous waste collection and temporary storage
facility at the Central Landfill. The facility will be open to collect hazardous materials on a weekly
basis. Hazardous materials will be transported to disposal sites outside Sonoma County.
SCWMA annually conducts hazardous waste education efforts. These education efforts include
distribution of a recycling guide to nearly all households in Sonoma County. The guide lists how
to avoid, store, and dispose of household hazardous materials. Ongoing public education campaigns
are funded by the SCWMA and grant funds.
Industrial and Commercial Hazardous Materials
State law requires that communities form a Consolidated Unified Protection Agency (CUPA). The
CUPA manages the acquisition, maintenance, and control of hazardous waste by industrial and
commercial businesses. Rohnert Park contracts with Sonoma County for this service.
HOUSEHOLD HAZARDOUS WASTE
Hazardous waste is generated in homes and businesses alike, and includes products such as paint,
batteries, fertilizers, and used motor oil. These wastes are of concern because they are often
improperly managed, resulting in injuries to sanitation workers and damage to collection vehicles,
as well as possible toxics leaching from sanitary landfills. Management of hazardous waste in
Rohnert Park occurs under the 1992 HHWE, which was incorporated into the Sonoma County
Hazardous Waste Management Plan.
The City’s HHWE addresses the wastes that stem from a variety of common household products.
Rohnert Park’s household hazardous waste management program, outlined in the HHWE,
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emphasizes public education, source reduction and recycling, mobile and permanent collection
facilities, and hazardous waste load checking. Household hazardous waste is collected and disposed
of by licensed haulers. Furthermore, SCWMA and the City created a network of private businesses
that collect used oil in Rohnert Park. In 1990, it was estimated that Rohnert Park residents generated
20 tons of hazardous waste per year – of which 13 tons are estimated to be either illegally disposed
of or stored in homes in Rohnert Park. Only four percent of Rohnert Park’s households participated
in the County Disposal Program in 1997.
The City currently participates in a SCWMA hazardous waste disposal program, allowing Rohnert
Park residents to dispose of hazardous waste in nearby cities. SCWMA plans to establish a
permanent collection facility at the Central landfill and reduce the periodic collection events in
urban areas.
HAZARDOUS MATERIALS DISPOSAL SITES
There are no hazardous material disposal sites in operation in the Rohnert Park area. All hazardous
waste is placed in containers and shipped to sites outside the community.
The Rohnert Park area does not contain any known historical hazardous material disposal sites.
Underground tanks containing petroleum products at scattered sites in the community may have
contaminated subsurface earth. Regular, highly detailed, laboratory testing of water from the city’s
wells, scattered throughout the community, has not detected contaminants from underground tanks
or other hazardous materials.
The City’s Department of Public Safety investigates illegal hazardous waste dumping. Most illegal
hazardous waste dumping in Rohnert Park consists of the disposal of oil and gasoline in storm
drains. Signs discouraging hazardous waste dumping were installed in 1997 above all storm drain
inlets in the city.
Hazardous Materials Transfer Station
The Safety Kleen Corporation operates a hazardous materials transfer station in Rohnert Park. The
total amount of hazardous materials stored at any given time is 2,000 gallons. Hazardous materials
are shipped to the company’s plant in Reedley, California, for treatment. The primary hazardous
material is 1,450 gallons per day, on average, of the mineral spirit Stoddard Solvent. In addition,
the transfer station stores approximately 40 gallons of Percloethylene (Perk), a cleaning solvent
used by dry cleaning businesses, and 40 gallons of lacquer thinner per day. Toxic materials are
obtained from an area extending from San Francisco to Eureka. The recycled materials are sold
back to the same businesses. The company does not treat or dispose of any hazardous materials on
the Safety Kleen site in Rohnert Park.
GOALS: HAZARDOUS MATERIALS
HS-E Minimize the risk to life and property from the generation, storage, and transportation of
hazardous materials and waste in Rohnert Park and assure the proper disposal of all
hazardous waste that may be generated in Rohnert Park.
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HS-F Comply with all applicable regulations and provisions for the storage, use and handling of
hazardous substances as established by federal (EPA), State (DTSC, RWQCB, Cal OSHA,
Cal EPA), and local (County of Sonoma, City of Rohnert Park) regulations.
HS-G Protect groundwater and soil from contamination by hazardous materials.
POLICIES: HAZARDOUS MATERIALS
HS-16 Promote joint, countywide programs to address the generation and disposal of hazardous
materials including the Sonoma County Hazardous Waste Management Plan.
HS-17 Develop and implement programs which provide convenient means for residents to
properly dispose of household hazardous waste materials.
HS-18 Support efforts to establish a permanent hazardous waste collection and temporary storage
facility at the Central Landfill.
This policy would allow hazardous waste collection events in Rohnert Park and other
nearby cities to be phased out. Given the risks of spills and accidents, it would be preferable
to have residents and businesses take hazardous waste to a controlled environment away
from built-up urban areas.
HS-19 Maintain existing signs discouraging hazardous waste dumping above all storm drain in
the city.
The signs should also note locations of current disposal sites.
HS-20 Support SCWMA in their hazardous waste education efforts.
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7.5 EMERGENCY MANAGEMENT
EMERGENCY PREPAREDNESS
The California Emergencies Services Act (State Government Code § 8550-8668) requires each city
to prepare and maintain an Emergency Plan for natural, manmade, or war-caused emergencies
which result in conditions of disaster or in extreme peril to life. Peacetime emergencies that should
be addressed by the Plan include earthquakes, fires, and floods. In 1995, the City adopted a
Standardized Emergency Management Plan, which describes the principles and methods to be
applied in carrying out emergency operations or rendering mutual aid during emergencies. The
Department of Public Safety (DPS) has developed the Standardized Emergency Management
System with Annexes, which is consistent with the requirements of the California Emergencies
Services Act. The System is updated and revised on an annual basis.
The Local Hazard Mitigation Plan (LHMP) for the City of Rohnert Park planning area,
incorporated herein by reference, was developed in accordance with the Disaster
Mitigation Act of 2000 (DMA 2000) and California Government Code Section 65302.6 and
follows FEMA’s 2011 Local Hazard Mitigation Plan guidance. The LHMP incorporates a
process where hazards are identified and profiled, the people and facilities at risk are
analyzed, and mitigation actions are developed to reduce or eliminate hazard risk. The
implementation of these mitigation actions, which include both short and long-term
strategies, involve planning, policy changes, programs, projects, and other activities. The
approved Local Hazard Mitigation Plan and related documents can be found on the City’s
Website at: https://www.rpcity.org/cms/One.aspx?portalId=3037873&pageId=15757359.
All City departments play a role in the plans and have specific assignments to perform in
emergencies. The City coordinates its planning with the County Office of Emergency Services to
keep the plans up to date. The City also participates in periodic city and countywide disaster drills
that are held to evaluate and critique emergency service preparedness. The Public Safety
Headquarters has been designed to function as an Emergency Operations Center for the community.
City emergency preparedness planning focuses on immediate threat to life and property. One
generally accepted rule-of-thumb is that citizens and businesses should not expect assistance until
72 hours after a disaster, unless there is an immediate threat to life or property. After a disaster,
municipal resources may be limited and must be dispatched to the most serious emergencies.
Earthquake Response
The City is prepared to meet the emergency service needs after a “worst case” earthquake. In 1995,
the City revised the “Threat Summary, Earthquake” section of the Standardized Emergency
Management Plan. This summary details the impacts of an earthquake of a magnitude of 8.3 on the
northern San Andreas Fault.
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Response to Hazardous Materials Spills
The City currently maintains a hazardous materials response plan. The Plan builds upon the
Sonoma County Operational Area Hazardous Materials Incident Response Plan. The goals of the
City’s hazardous materials planning are to contain and identify hazardous materials spills and to
implement evacuation, clean up, and disposal.
The DPS maintains a hazardous materials team. Members of this team have completed extensive
training and qualify as Hazardous Materials Technicians or Specialists. Should a hazardous
materials event occur within the city, the hazardous materials team will take a leading role in
protecting the public. The team will follow general response guidelines but must fit the response to
the specific incident.
Numerous types of hazardous materials are transported on US 101. The California Highway Patrol
is responsible for hazardous materials accidents on the Highway. The City maintains
communication links with these agencies and participates, as necessary, in responses to hazardous
materials accidents.
EMERGENCY MEDICAL CARE
Sonoma Life Support provides ambulance service in Rohnert Park. Sonoma Life Support is a
private emergency medical provider that was granted the contract to provide emergency services
for the central Sonoma County Franchise area in 1991. The purpose of the franchise is to provide
emergency medical services to all sectors of the population regardless of ability to pay, support the
system through fees and minimize cost through public regulation of the service provider. Sonoma
County monitors the service provider, ensuring that Sonoma Life Support maintains the required
service levels.
A single ambulance station serves the City of Rohnert Park. The station is housed in leased space
generally located near the center of the city. Units located elsewhere in the county provide backup
service as needed. A paramedic and other necessary staff at all times staff the station. Emergency
services are provided 24 hours a day, seven days a week. The ambulance contains full
communications including radio and phone linking the ambulance with the Santa Rosa and
Petaluma hospitals.
POLICE, FIRE, AND RELATED SERVICES
DPS provides police, fire, and related services in the community according to the public safety
administrative concept. Cross-trained personnel under a single administrative umbrella furnish
police and fire services.
Key procedures help implement the public safety concept in Rohnert Park. First, DPS personnel
are issued personal pagers and home alert devices. This allows personnel to be contacted by
dispatchers in cases when additional staff is needed during an emergency. Second, public safety
officers must live within a reasonable proximity to the community. Third, the City issues vehicles
to officers. The vehicles are parked at officers’ homes during off-duty hours. Officers carry fire
Chapter 7: Health and Safety
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turnout gear, water and dry chemical fire extinguishers, emergency medical, and other items in
their vehicle.
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GOALS: EMERGENCY MANAGEMENT
HS-H Use the Standardized Emergency Management Plan as the guide for emergency management
in Rohnert Park.
HS-I Cooperate with other public agencies to store, organize, distribute, and administer
emergency medical equipment, supplies, services and communication systems.
HS-J As part of the concurrency requirement for development on the westside, construct a public
safety station west of US 101 in the general vicinity of the Wilfred Avenue/Labath Avenue
intersection.
A Westside station will be necessary if additional construction occurs west of US 101 in
order to respond to emergency calls within an acceptable response time. If the station were
located in the general vicinity of the Wilfred Avenue/Labath Avenue intersection,
emergency vehicles could respond within four minutes to calls in the area west of US 101.
POLICIES: EMERGENCY MANAGEMENT
HS-21 Maintain and regularly update the Standardized Emergency Management Plan.
The Department of Public safety shall administer the plan and revise it as needed.
Evacuation routes should be adopted and updated as part of the plan. The routes should
be flexible to respond appropriately to various emergencies (such as exposure to
hazardous materials, flood, fire, or earthquake).
HS-22 Conduct periodic emergency management exercises to familiarize key City personnel and
surrounding jurisdictions and agencies with their roles and responsibilities to ensure
emergency facilities will function in the event of a disaster.
HS-23 Prepare and disseminate information to help households prepare for emergency situations.
This information should include pre-fire and earthquake plans, guidebooks, and
instruction kits identifying how emergency response will be coordinated and how
evacuation of residents will proceed. Households should be encouraged to take the
necessary preparations to be self-sufficient for at least 72 hours after a disaster strikes the
community.
HS-24 Require adequate access for emergency vehicles, including adequate street width and
vertical clearance, on new streets.
The DPS should establish street width, vertical clearance, and access standards in the
Standardized Emergency Management Plan.
HS-25 Ensure that new traffic signals include a system which allows emergency vehicles to
change the signal.
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HS-26 Locate a new public safety station in the Stadium Lands Planned Development; require
new development on the west side (west of Highway 101) to contribute funds to the Public
Facilities Financing Plan for construction.
The Wilfred-Dowdell Village Specific Plan establishes a Public Facilities Financing Plan
to provide funding for a new station. The Wilfred-Dowdell Village development is
providing a portion of the total funding required; other development benefiting from the
station will also be required to contribute. The new station on the westside is expected to
require seven additional public safety staff, whose salaries would be provided through the
General Fund.
ROHNERT PARK - LHMP
City of Rohnert Park - 2018
Local Hazard Mitigation
Plan
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ROHNERT PARK - LHMP i
Table of Contents
Introduction........................................................................................................................................................................................ 1
Purpose ............................................................................................................................................................................................. 1
Compliance ...................................................................................................................................................................................... 2
Mitigation Goals and Priorities ......................................................................................................................................................... 4
Planning Process ................................................................................................................................................................................ 5
FEMA Element A: Planning Process ................................................................................................................................................ 5
Scoping and Kick-Off ....................................................................................................................................................................... 5
Schedule and Process ........................................................................................................................................................................ 6
Team Members ................................................................................................................................................................................. 7
Public Outreach and Stakeholder Involvement Opportunities ............................................................................................................ 8
Review of Existing Plans and Technical Information ...................................................................................................................... 10
Physical Setting and Community Profile ........................................................................................................................................ 11
Physical Setting .............................................................................................................................................................................. 11
Historic and C urrent Conditions...................................................................................................................................................... 12
Community Profile ......................................................................................................................................................................... 12
Land Use ........................................................................................................................................................................................ 14
Downtown Development ................................................................................................................................................................ 16
Housing Development .................................................................................................................................................................... 17
Population Data .............................................................................................................................................................................. 18
Economic Trends ............................................................................................................................................................................ 22
Critical F acilities ............................................................................................................................................................................ 23
Hazard Identification, Analysis, and Assessment .......................................................................................................................... 29
FEMA Element B: Hazard Identification and Risk Assessment ....................................................................................................... 29
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Hazard Prioritization ....................................................................................................................................................................... 31
Primary Hazard Profiles .................................................................................................................................................................. 32
Earthquake (Shaking) ............................................................................................................................................................. 34
Earthquake (Liquefaction) ...................................................................................................................................................... 36
Flooding (Local) ..................................................................................................................................................................... 41
Flooding (FEMA) ................................................................................................................................................................... 47
Drought .................................................................................................................................................................................. 50
Wildfire/Wildland-Urban Interface Fir e .................................................................................................................................. 55
Minor or Secondary Hazard Profiles ............................................................................................................................................... 63
Hazardous Materials ............................................................................................................................................................... 63
Landslide ................................................................................................................................................................................ 64
Dam Inundation ...................................................................................................................................................................... 68
Earthquake Faulting ................................................................................................................................................................ 69
Summary of Vulnerabilities ............................................................................................................................................................ 71
Vulnerability Analysis .................................................................................................................................................................... 72
Social Vulnerability Analysis .......................................................................................................................................................... 81
Mitigation and Adaptation Strategy ................................................................................................................................................ 82
FEMA Element C: Mitigation Strategy ........................................................................................................................................... 82
Mitigation Goals ............................................................................................................................................................................. 83
Mitigation Activities ....................................................................................................................................................................... 88
Capabilities Assessment .................................................................................................................................................................104
Plan Maintenance and Adoption Process .......................................................................................................................................112
FEMA Element D: Plan Review, Evaluation, and Implementation .................................................................................................112
Coordinating Group .......................................................................................................................................................................112
Plan Update Process ......................................................................................................................................................................114
Adoption and Implementation Process ...........................................................................................................................................115
FEMA Comments and Tips ...........................................................................................................................................................116
Technical Appendices and Documents ..........................................................................................................................................116
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List of Tables
Table 2.1: Potential Housing Growth by Development Area ............................................................................................................... 18
Table 2.2: Population and Housing Data Comparison ......................................................................................................................... 19
Table 2.3: Race and Ethnicity Data Comparison ................................................................................................................................. 20
Table 3.1: Critical Facilities ............................................................................................................................................................... 23
Table 3.2: Parks, Recreation Facilities, and Open Space ..................................................................................................................... 25
Table 3.3: Infrastructure ..................................................................................................................................................................... 26
Table 3.4: Evaluated Hazards ............................................................................................................................................................. 30
Table 3.5: Hazard Criteria Ranking Scores and Weighing Factors ...................................................................................................... 31
Table 3.6: Scores and Threat Levels for Included Hazards ................................................................................................................. 32
Table 3.7: Wildfire Hazard History and Extent ................................................................................................................................... 60
Table 4.1: Vulnerability Analysis ....................................................................................................................................................... 72
Table 4.2: Infrastructure Vulnerability and Exposure.......................................................................................................................... 78
Table 4.3: Community-Wide Social Vulnerability Metrics ................................................................................................................. 81
Table 5.1: STAPLE/E Criteria ............................................................................................................................................................ 86
Table 5.2: Mitigation Actions ............................................................................................................................................................. 88
Table 5.3: Available Resources .........................................................................................................................................................104
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APPENDICES
Appendix A – Acronyms, Abbreviations, and Glossary
Appendix B – Planning Process Documents
Appendix C – Mapping
Appendix D – 2010 ABAG Annex and 2009 Mitigation Spreadsheet
Appendix E – Supplemental Materials
Appendix F – Plan Review
Appendix G – FEMA Comments
ROHNERT PARK - LHMP 1
INTRODUCTION
Purpose
No one is free of natural hazards which may vary across landscapes and time. With Natural hazards comes disasters that can cause
loss of life, and damage to our built environment resulting in depletion of the community’s economic, social, and environmental well-
being. Resiliency and adaptation is crucial, because a community must have sustained ability to use available resources to respond to,
withstand and recover from adverse situations. It is the responsibility of the City to protect the health, safety, and welfare of our
residents. This LHMP sets in stone the community’s emergency management activities that address preparedness, response, recovery
and mitigation.
The City of Rohnert Park Local Hazard Mitigation Plan:
• Meets the requirements of federal assistance grant programs, including FEMA’s Hazard Mitigation Grant Program (HMGP)
and Pre-Disaster Mitigation (PMD) funding.
• Works in conjunction with other plans, including the City’s General Plan and the City’s Emergency Management Plan.
• Establishes a basis for coordination and collaboration among community entities such as private and public agencies, key
stakeholders, and residents to provide for the fullest amount of transparency.
• Identifies and prioritizes future mitigation projects.
The term “Hazard” is defined by FEMA as “any event or physical condition that has the potential to cause fatalities, injuries, property
damage, infrastructure damage, agricultural losses, damage to the environment, interruption of business, or other types of harm or loss.
Hazard Mitigation is defined as “any sustained action taken to reduce or eliminate long term risk to human life and property from
natural, human-caused, and technological hazards and their effects.”
A hazard mitigation plan should not be confused with emergency response or preparedness plans that are focused on being ready
and responding when a hazard or disaster event occurs and may include such actions as providing emergency response, equipment,
food, shelter, and medicine. However, hazard mitigation and emergency preparedness go hand-in-hand and are part of the City’s
multi-pronged approach to minimizing personal injury and property damage from Hazards in the residential and commercial areas. It
compliments other planning documents and regulatory authorities governing pre-disaster land use planning and post-disaster response
and recovery.
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Compliance
FEMA Regulations
The Federal Emergency Management Agency’s (FEMA) mission:
“to support our citizens and first responders to ensure that as a nation we work
together to build, sustain and improve our capability to prepare for, protect against,
respond to, recover from and mitigate all hazards.”
Hazard mitigation planning is directed by the Robert T. Stafford Disaster and Relief and
Emergency Assistance Act (Stafford Act), as amended by the Disaster Mitigation Act of
2000 (DMA 2000). DMA 2000 amended the Stafford Act to require state, local, and tribal
governments to develop and submit to FEMA a mitigation plan that outlines processes for
identifying the natural hazards, risks, and vulnerabilities of the jurisdiction. Plan approval
by FEMA is a prerequisite to receiving federal hazard mitigation grant funds (see 42 USC
Section 5165(a)).
To implement the mitigation planning requirements of the Staffor d Act, FEMA
promulgated 44 Code of Federal Regulations (CFR) Part 201, the federal regulations
gover ning the planning process, plan content, and the process for obtaining approval of the
plan from FEMA. The planning requirements set forth in the CFR, including plan revision
requirements, are identified through the FEMA Regulation Checklist in the Local
Mitigation Plan Review Tool. Local Mitigation Plans must be updated once every five years in order to continue to be eligible for
FEMA hazard mitigation project grant funding. Specifically, 44 CFR 201.6(d)(3) reads:
A local jurisdiction must review and revise its plan to reflect changes in development, progress in local mitigation efforts, and
changes in priorities, and resubmit it for approval within (5) years in order to be eligible for mitigation project grand funding.
For FEMA approval, all Elements including su b-element must be met with current information. The Rohnert Park Local Hazard
Mitigation Plan (LHMP) complies with the DMA 2000, Federal Register 44 CFR Parts 201 and 206, Section 322, Mitigation
Planning. This law, as of November 1, 2004, requires local governments to develop and submit hazard mitigation plans as a condition
of receiving Hazard Mitigation Grant Program (HMGP) and other mitigation project grants.
Figure 1.1: LHMP Handbook
CITY OF ROHNERT PARK - 2018 LOCAL HAZARD MITIGATION PLAN
ROHNERT PARK - LHMP 3
State of California
In addition to the requirements listed above, the State of California has also enacted revisions to California Government Code Sections
8685.9 and 65302.6 (commonly known as Assembly Bill [AB] 2140 [Chaptered 2006]) which addresses the requirements to have a
local hazard mitigation plan. Excerpts of these government code sections are included below.
California Government Code Section 8685.9:
Notwithstanding any other provision of law, including Section 8686, for any eligible project, the state share shall not exceed 75
percent of total state eligible costs unless the local agency is located within a city, county, or city and county that has adopted a local
hazard mitigation plan in accordance with the federal Disaster Mitigation Act of 2000 (P.L. 106-390) as part of the safety element of
its general plan adopted pursuant to subdivision (g) of Section 65302. In that situation, the legislature may provide for a state share of
local costs that exceeds 75 percent of total state eligible costs.
California Government Code Section 65302.6:
(a) A city, county, or a city and county may adopt with its safety element pursuant to subdivision
(g) of Section 65302 a local hazard mitigation plan (HMP) specified in the federal Disaster
Mitigation Act of 2000 (Public Law 106-390). The hazard mitigation plan shall include all of the following elements called for
in the federal act requirements:
(1) An initial earthquake performance evaluation of public facilities that provide essential services, shelter, and critical
governmental functions.
(2) An inventory of private facilities that are potentially hazardous, including, but not limited to, multiunit, soft story, concrete
tilt-up, and concrete frame buildings.
(3) A plan to reduce the potential risk from private and governmental facilities in the event of a disaster.
(b) Local jurisdictions that have not adopted a local hazard mitigation plan shall be given preference by the Office of Emergency
Services in recommending actions to be funded from the Pre-Disaster
Mitigation Program, the Hazard Mitigation Grant Program, and the Flood Mitigation Assistance
Program to assist the local jurisdiction in developing and adopting a local hazard mitigation plan, subject to available funding from
the Federal Emergency Management Agency.
This LHMP includes the information required by California Government Code Sections 8685.9 and 65302.6.
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Plan Use
Individual components of the LHMP provide information and resources to assist citizens and city staff in comprehending the potential
hazard related issues facing the City of Rohnert Park. The structure of the plan is intended to enable users to quickly and easily access
and understand each section as necessary. The structure allows the City of Rohnert Park to assess and update sections with new and
additional data as it becomes available. This is designed to increase the ease of the updating process – resulting in a more practical and
relevant plan.
Mitigation Goals and Priorities
The City of Rohnert Park established LHMP mitigation priorities and goals as a component of the planning process in order to guide
the development of a thorough plan. The goals were developed by the planning team and drawn from the previous LHMP and the
City’s General Plan. The mitigation goals and priorities for the LHMP are:
1. Implement the Local Hazard Mitigation Plan to increase Rohnert Park’s
level of preparation for potential disasters and to minimize the impacts
associated with natural and man-made hazards.
2. Identify strategies and tools to facilitate community disaster and hazards
awareness and education.
3. Provide for the safety of Rohnert Park citizens by maintaining efficient, well-
trained, and adequately equipped City personnel.
4. Encourage a disaster-resistant City and surrounding area by reducing the
potential for loss of life, property damage, and environmental degradation from
disasters and hazards.
5. Reduce the vulnerability of public and private facilities and infrastructure to
the effects of earthquakes, flooding, and drought.
6. Promote conditions and strategies that will accelerate the capacity for
physical and economic recovery from disasters and hazards.
Figure 1.2: Mitigation Cycle
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PLANNING PROCESS
The Rohnert Park LHMP Planning process was defined from the get-go by the community and its needs. Bringing together local
officials, stakeholders and the public in a community‐driven plannin g process to develop the plan also helps build the community’s
overall hazard mitigation program. The LHMP is the written record, or documentation, of the planning process. This is why some of
the plan requirements ask for a “discussion” or “description” of generally, what must be documented in the plan, rather than specify
exactly how it must be done. Element A dictates the requirements for what should be included in the Planning Process.
FEMA Element A: Planning Process
• A1. Does the Plan document the planning process, including how it was prepared and who was involved in the process for each
jurisdiction? 44 CFR 201.6(c)(1)
• A2. Does the Plan document an opportunity for neighboring communities, local and regional agencies involved in hazard
mitigation activities, agencies that have the authority to regulate development as well as other interests to be involved in the
planning process? 44 CFR 201.6(b)(2)
• A3. Does the Plan document how the public was involved in the planning process during the drafting stage? 44 CFR 201.6(b)(1)
and 201.6(c)(1)
• A4. Does the Plan document the review and incorporation of existing plans, studies, reports, and technical information? 44 CFR
201.6(b)(3)
• A5. Is there discussion on how the community(ies) will continue public participation in the plan maintenance process? 44 CFR
201.6(c)(4)(iii)
• A6. Is there a description of the method and schedule for keeping the plan current (monitoring, evaluating and updating the
mitigation plan within a 5‐year cycle)? 44 CFR 201.6(c)(4)(i)
Scoping and Kick-Off
Planning for the City of Rohnert Park’s Local Hazard Mitigation Plan can be traced back to the summer of 2016 when the City
became aware that the 2010 Association of Bay Area Governments and accompanying Rohnert Park specific annex had expired. A
review of available literature including FEMA and State guides was commenced. The team initially assembled in late September with
an official initial kick-off meeting held on October 5, 2016. The team was primarily composed of City staff, specifically members of
the Development Services Department. Additional team members from the Administrative Unit, Public Works, and Public Safety
were also included. An ambitious scope of work was developed. While the general outline of the scope was followed in the
preparation and completion of the plan, the overall timeline did get extended.
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Schedule and Process
Meetings and events were held on the following dates:
• October 5, 2016 – Team Meeting: discussed
LHMP process and team member roles; began
preparation of the public involvement campaign.
• October 20, 2016 – Team Meeting: reintroduced
project with more team members, refined plan
for public engagement
• November 2, 2016 – Community Open House
and Presentation: open house focused on
emergency preparedness followed by
presentation and Q&A session about the LHMP.
• November 10, 2016 – Planning Commission:
provided update to planning commissioners on
project and solicited their ideas and feedback
• November 16, 2016 – Team Meeting: recap of activities and steps to date, mapping refinement, risk assessment and critical
facilities inventory
• December 9, 2016 – Team Meeting: mapping updates and mitigation goal setting exercise
• January 10, 2017 – Team Meeting: discussed further mitigation goals and activities, discussed critical facilities and
vulnerabilities
• January 31, 2017 – Team Me eting: draft mitigation measures and activities
• August 31, 2017 – Team Meeting: update on draft and current status of tasks, preliminary discussions regarding further
outreach
• September 14, 2017 – Team Meeting: review draft and updated completion timeline, refine plans for public outreach
• September 20, 2017 – Community Open House and Presentation: present draft to public during open house
• TBD, 2017 – Presentation to Sonoma County Area LHMP Task Force
• November 1, 2017 – Planning Commission
• November 28, 2017 – City Council
Figure 1.3: November 2016 Community Open House
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Team Members
The planning team for the LHMP was made of various city staff members representing a cross-section of relevant departments within
the City of Rohnert Park. Team members brought a variety of strengths and backgrounds to the group.
• Mary Grace Pawson, Director of Development Services – Provided overall guidance and supervision for the team and project.
• Jeffrey Beiswenger, Planning Manager, Development Services – Served as the primary point person in terms of Planning
Documents.
• Zach Tusinger, Planner II, Development Services – Overall
project manager, responsible for coordination, plan assembly,
and drafting.
• Jay Bradford, Building Official, Development Services –
Technical advisor regarding building standards and assessment
of city facilities.
• Caitlin Saldanha, Deputy City Clerk – Administration liaison.
Responsible for community outreach coordination.
• Marc Bautista, Environmental Coordinator (until March 2017) –
Contributed information regarding flooding and infrastructure.
• Nick Bennett, Environmental Coordinator (from August 2017) –
Provided supplemental information regarding flooding.
• Jim Thompson, Fire Marshal – Served as Public Safety liaison
and provided technical expertise regarding preparedness and
hazards.
• Jahfer Aguirre, GIS Analyst – Synthesized data and prepared
maps and exhibits for outreach events, analysis, and the plan
itself.
• Bonnie Betts, Planning Intern, Development Services – Created the plan template, and contributed to plan and appendices
preparation.
• Kevin Locke, Planning Intern, Development Services – Revised the plan based on CalOES comments and contributed to
updating and creating new sections.
Figure 1.4: Rohnert Park City Hall
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Public Outreach and Stakeholder Involvement Opportunities
Letters were sent out to multiple neighboring communities requesting
input and review of the plan, including; Cotati, Santa Rosa, and the
County of Sonoma. No formal response was given from any city. But,
Rohnert Park entered cooperative agreements to mitigate hazards wit h
Cotati and Santa Rosa. As well, Letters were sent to stakeholders to
provide review and input regarding the plan. Multiple opportunities for
public participation were offered throughout the planning, drafting, and
approval processes. The planning team held an event at the Rohnert
Park-Cotati Library on the evening of November 2, 2016. This was an
opportunity for the team to present some of its initial findings and ideas
(as well as draft components of the plan – primarily maps) to citizens
and other inter ested stakeholders. The team felt like this was a great
opportunity to invite other relevant departments and agencies to be
available with information and materials.
The first thirty minutes of the event were geared as an open house with various booths ran
by stakeholders, many focused on safety, emergency preparedness, and resiliency. Booths
were run by Sonoma-Marin Area Rapid Transit (SMART), The Fire & Emergency Services
Department of Sonoma County -- Sonoma County Alerts (SoCo Alerts), the Rohnert Park
Pet Shelter, the American Red Cross, The Rohnert Park Department of Public Safety, and
The Rohnert Park Department of Public Works (to share information about their
sandbagging program). The remaining hour of the event was reserved for a presentation by
the planning team as well as a question and answer session, where community members
provided initial feedback and reactions to the planning process. A copy of the PowerPoint,
advertising materials, and handout are included in the Appendix. Much time was spent at
the meeting discussing the differences between emergency preparedness and response, and
mitigation.
Figure 1.5: Community Meeting Flyer
Figure 1.6: Resiliency Concept
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Earthquakes were a primary concern of the residents who attended. The memory of the 2014 Napa earthquake was still fresh in
everyone’s minds, and while there was not any significant damage in Rohnert Park from that earthquake, the shaking was felt within
the City.
After the meeting, main points and ideas from the public were taken into consideration. A summary input from the November 2nd
meeting includes:
• Identifying and assessing the risk of impact and mitigate (structural, physical changes, things like building a wall a little bit
stronger or reinforcing something, planning or zoning, education, awareness of options.)
• Identifying critical facilities.
• Mobile home park preparedness for seniors. Mobile home parks looks to be a big focus.
• What are the mitigation activities? Outline goals, objectives and priorities.
• Plan for if technology is not available to be used. (Power outages, no communication, etc.)
• Identify real concrete steps that can actually be implemented, look for measurable goals, look for benchmarks we can set when
we evaluate this down the line, and things cost money so we have to look for funding sources for those whether it comes from
local sources or the state or the federal government or possible grants.
Each of these ideas were deemed to be related to Rohnert Park and has been included within the Hazard Mitigation Plan. Other
provided input was considered but was found to be unrelated to hazards specifically in Rohnert Park.
Public Review Draft
On September 20, 2017, the City of Rohnert Park made available the public review draft of the Rohnert Park LHMP. The completed
draft was released to the general public for review and comment for a period of more than 30 days. Letters were sent to relevant
stakeholders and area agencies letting them know that the draft was available and directing them to an electronic copy for their review
and comment. Physical copies of the document were placed at the public counter in Development Services, with the Department of
Public Safety, and with the City Clerk.
On the same day, the City held a community meeting to present the general outcomes of the planning process, to discuss mitigation
goals and activities, to solicit additional feedback from members of the public, and to describe the next steps in the plan approval and
adoption process
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Review of Existing Plans and Technical Information
The planning team relied on many already existing plans and technical information to help guide hazard mapping, public discussions,
and developing the LHMP. Existing information can be found in the appendix, and includes:
Source Relation to LHMP
Taming Natural Hazards – Association of
Bay Area Governments (ABAG) Multi-
Jurisdictional Local Hazard Mitigation
Plan for the San Francisco Bay Area
2010
Determining risks related to Rohnert
Park.
City of Rohnert Park - Annex to 2010
ABAG Plan
Providing guidance on goals and
priorities for Rohnert Park.
City of Rohnert Park – 2009 ABAG
Mitigation Goals Spreadsheet
Used as a reference for current
mitigation actions.
City of Rohnert Park Emergency
Management Plan 2012
Aided in providing effective
mitigation actions to ensure smart
emergency response.
City of Rohnert Park General Plan 2020,
8th Edition
Set goals and priorities for the plan.
Sonoma County Hazard Mitigation Plan
2016
Provided maps and graphics such as
the fire risk map (Figure 3.17).
City of Santa Rosa Hazard Mitigation
Plan 2016
Used as reference for organization of
plan.
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PHYSICAL SETTING & COMMUNITY PROFILE
Physical Setting
Rohnert Park is located in central Sonoma County along US 101. It is the county’s third
largest city. The Pacific Ocean to the west with its cool marine air, and the warm Sonoma
Valley to the east combine to create a mild climate. Rohnert Park lies within the Cotati
Valley, with coastal hills to the west and the Sonoma Mountains to the east. Sonoma State
University sits just outside Rohnert Park’s eastern boundary. Rohnert Park is comprised of
approximately 6.9 square miles and with an elevation of 105 feet above sea level. The
City has a population of about 40,971 people, based on 2010 census information.
Rohnert Park was founded as a master-planned community on the former site of the
Rohnert Park Seed Farm. Thoughtfully designed for families, bikeways, and walkways
connect its tree-lined boulevards. Several creeks run into the city from the eastern
ridgeline. The city is surrounded by farms and grazing land.
Rohnert Park is located in the Santa Rosa-Petaluma Valley where the underlying geologic
structure is characterized by sediments deposited by streams on floodplains, alluvial deposits, and basins. Overall, general geologic
conditions, slopes, and soils do not vary significantly from one part of the city to another.
There are no known active faults within Rohnert Park. The Healdsburg-
Rodgers Creek fault zone lies approximately 5 miles to the east of the city.
The San Andreas Fault System is located approximately 15 miles west of
the city. Secondary seismic hazards that could affect Rohnert Park include
ground-shaking, liquefaction, and ground settlement.
Elevations range between 230 feet above mean sea level northeast of the
city to 90 feet above mean sea level on the western boundary of the city.
Given the relatively flat topography and the nature of soils, there is little
risk of mudslides, landslides, or erosion in the immediate Rohnert Park
area. Soil liquefactio n has the potential to impact the Rohnert Park area
during a seismic event. Soils underlying almost the entire area within the
city exhibit moderate susceptibility to liquefaction (City of Rohnert Park
Emergency Management Plan 2012).
Figure 1.7: Emergency Management Plan
Figure 2.1: Rohnert Park Location
Figure 2.2: Rohnert Park US 101 Sign
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Community Profile
When gathering data regarding the community profile of Rohnert Park, staff looked towards the 2016 Rohnert Park Local Economic
Profile. This document was published by The Sonoma County Economic Development Board (EDB), in partnership with the Sonoma
County Workforce Investment Board (WIB), the City of Rohnert Park, and the Rohnert Park Chamber of Commerce. This document
offers projections through 2020 that is useful when looking at economic, and social trends.
Historical Context
Beginning in the fall of 1954 a plan for a new town
north of Cotati in Sonoma County was beginning to
emerge. The core of the plan was the "Neighborhood
Unit" concept. The plan was a modification of
Pennsylvania's Levittown. It provided that each
neighborhood would consist of 200-250 homes centered
on a 10-acre school site and 5 -acre pool-park site. No
child would have to walk more than 1/3 of a mile to
school; the school would be the nucleus of a cohesive
community. The commercial and industrial development
would be large enough and diverse enough to support
the entire community. Eight such subdivisions would
constitute a city of 30,000 people. With planned pools,
parks, and service the city would be a "country club for
the working class".
On August 28, 1962, Rohnert Park was officially
incorporated: 1,325 acres, housing an estimated 2,775
persons. It was the fourt h largest city in Sonoma County
and the first town to incorporate since 1905.
Since 1962, Rohnert Park has grown incrementally into a town of over 40,000 people across numerous neighborhood sections (see
Figure 2.4). Today, Rohnert Park is also the home for Sonoma State University, and is the gateway for Graton Resort & Casino.
Figure 2.3: Rohnert Park Aerial Circa 1960s.
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Figure 2.4: Rohnert Park Neighborhood Section Map
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Existing Land Use and General Plan
Existing land use information was taken from the Rohnert Park
General Plan. Specific Details came from the Land Use Element,
Specific Plans, and the adopted Zoning Map. The documents
used to implement the General Plan are the zoning code
inclusive of the various specific plans.
The Rohnert Park General Plan is a document required by State
law and adopted by the City Council that is a comprehensive,
long -term plan for the physical deve lopment and growth of the
city. It is the city's "constitution" for development; the
framework within which decisions on how to grow, provide
public services and facilities and protect and enhance the
environment are made.
The land use framework of the General Plan is embodied in the
General Plan Diagram, a graphic representation of the themes
and policies in the Plan. The General Plan Diagram designates
the proposed general location, distribution, and extent of land
use throughout the City.
The Planning Division is responsible for regularly updating the
City's General Plan Housing Element. The purpose of the
Housing Element is to make adequate provisions for the existing
and projected housing needs of all economic segments of the
community and to determine how the city will meet its fair share
of regional housing needs. The California Department of
Housing and Community Development has found that the most
recent update, adopted by the City Council in November of
2014, is in full compliance w ith State Housing Element Law. Figure 2.5: Rohnert Park General Plan Map
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Specific Plan and Other Areas
Specific Plans
A Specific Plan is a tool for the systematic implementation of the
General Plan. It effectively establishes a link between implementing
policies of the General plan and the individual development proposals in
a defined area. A Specific Plan may be as general as setting forth broad
policy concepts, or as detailed as providing direction to every facet of
development from the type, location and intensity of uses to the design
and capacity of infrastructure, from the resources used to finance public
improvements to the design guidelines of a subdivision.
Planned Development
The Planned Development (P-D) zoning district is intended to
accommodate a wide range of residential, commercial and industrial land
uses, which are mutually-supportive and compatible with existing and
proposed development on surrounding properties. P-D zoning districts
shall encourage the use of flexible development standards designed to
appropriat ely integrate a project into its natural and/or man-made setting
and shall typically be intended for projects that provide for a mix of land
uses to serve identified community needs. Furthermore, the P-D zoning
process may be used to implement the various specific plans adopted by
the city. Once established, the P-D zoning district becomes, in effect the
zoning for the area within its respective boundaries. New development
within Rohnert Park is not expected to change hazard vulnerability.
Priority Development Area Plan
Priority Development Areas, known as PDAs, are areas within existing
communities that city or county governments have identified and
approved for future growth. PDAs are accessible by one or more transit
services and are often located near established job centers and shopping districts.
Figure 2.6: Rohnert Park Development Areas
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Downtown Development Trends – Priority Development Area Plan
Creating a Vision for Central
Rohnert Park, in March 2016, the
City Council adopted the Central
Rohnert Park, Priority
Development Area Plan, along with
related General Plan and Zoning
Ordinance Updates. The plan covers
an approximately 330-acre
developed area of the city, roughly
centered along Rohnert Park
Expressway and State Farm Drive.
The plan features the creation of a
new Downtown District – approximately 50 acres in size, to create a hub of
activity within Central Rohnert Park. The downtown is envisioned to include a
vibrant mix retail, office and residential uses, centered at the intersection of
Rohnert Park Expressway and State Farm Drive. A key destination in
downtown will be the new train platform for the SMART train, which recently
completed testing and has entered full revenue service. This new development is
not expected to affect or change Rohnert Park’s vulnerability to hazards.
In addition to the new Downtown, the Central Priority Development Area Plan
will help incentive the construction of the following development over the next
20 or so years: over 800 residential units (concentrated within the one-half mile
radius of the SMART rail station); up to 450,000 square feet of retail and
services; up to 200,000 square feet of new office facilities; up to 60,000 square
feet of public buildings; up to 130,000 square feet of light industrial uses; and
8.5 acres of public parks and a comprehensive network of bicycle and walking
pathways.
Figure 2.8: New Construction
Figure 2.7: Central Rohnert Park PDA
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Housing Development
Over the last five years (2012-2016) a total of 1,753 new housing
units have received final discretionary approvals. The bulk of these
are planned to be constructed in the University District. Over that
same period 506 units were included in Final Map approvals. The
number of building permits approved over the last five years for
new housing totals 464. The bulk of those permits have been issued
in either the Stadium Lands area or the University District. This
new housing is expected to have flood risk involved due to five
creek and Hinebaugh Creek. But, in order to prevent further risk,
Rohnert Park is developing retention basins to protect flood risk
and wildfire risk. This will be discussed further in the mitigation
actions.
Building Permits for model homes in Southeast Rohnert Park are
expected to
begin being
issued before
the end o f
2017.
Additional
multi-family
developments
have been
approved on
both sides of
Highway 101.
Figure 2.10: New Housing in the University District
Figure 2.9: Recent Housing Development
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Potential Housing Growth
Table 2.1: Potential Housing Growth by Development Area
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Population Data
2010 2015
Total Population 40,971 41,651
Male 19,793 19,221
Female 20,728 22,430
Total Housing Units 16,000 16,424
Median Household Income $51,942 $58,719
Median House Value $300,000 $511,000
Source all: Bay Area Census 2010, ACS 2015, & 2016 Rohnert Park: Local Economic Profile
When looking at potential population growth and change as we move
closer to the year 2020, the population bracket of 65 and older is expected
to increase the greatest amount by 2020. While more people are moving
into the age of retirement this is creating a decrease in individuals 10-24
and 45-64 between 2015 and 2020. This population growth is not
expected to change the risk of hazards within Rohnert Park.
Table 2.2: Population and Housing Data Comparison
Figure 2.11: Population Comparison
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Race and Ethnicity Data
Race and Ethnicity Population
(2010)
Percentage of Population
(2010)
Population
(2015)
Percentage of Population
(2015)
White 31,178 76.1% 31,065 74.6%
Black or African American 759 1.9% 916 2.2%
American Indian and Alaska
Native
407 1.0% 261 0.6%
Asian 2,144 5.2% 2,658 6.4%
Native Hawaiian and Other
Pacific Islander
179 0.4% 147 0.4%
Other Race 3,967 9.7% 4.022 9.7%
Two or More Races 2,337 5.7% 2,582 6.2%
Hispanic or Latino (of any race) 9,068 22.1% 10,035 24.1%
Source: Bay Area Census 2010, United States Census 2010, American Community Survey, 2015
According to the Sonoma
County’s 2016 Rohnet Park
Local Economic Profile as the
community moves closer to the
year 2020, a new trend
developing is the increase of
the hispanic population within
the City of Rohnert Park.
Between 2010 and 2020 there
is predicted to be a 4
percentage point increase.
Table 2.3: Race and Ethnicity Data Comparison
Figure 2.12: Race and Ethnicity Data Comparison
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Educational Attainment
The information and pie chart below are obtained from the 2016
Rohnert Park Local Economic Profile. In 2015 the population
of those 25 and older, 23% of residents had obtained a High
School Diploma. This is higher than Sonoma County in the
same year with 20% of residents obtaining diplomas. The
category of Some College, consisting of individuals who have
taken college courses but who have never received their degree.
In 2015, about 18% of residents had obtained a Bachelor’s
Degree and around 7% had received a Graduate or Professional
Degree.
Figure 2.13: Educational Attainment
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Economic Trends & Employment
Rohnert Park is located in Sonoma County which is a world destination for tourism. A local Economic Profile of Rohnert Park
completed by the City and Sonoma County in 2016 illustrates how the diverse economy and economic growth in the larger Bay Area
has impacted Rohnert Park. Tourism is not expected to have an increase on hazard risk for Rohnert Park.
Rohnert Park’s seasonally unadjusted unemployment rate was 4.5% in June 2015, higher than Sonoma County (4.3%) for the same
month. Compared to June of the previous year, Rohnert Park’s unemployment rate is down 1.2 points from 5.7%. Unemployment
remains significantly lower in Rohnert Park compared to its peak of 11% in March of 2010. Rohnert Park’s unemployment rate is
below the state (6.2%), as well as the nation (5.5%).
Total employment in Rohnert Park was 22,100 in June 2015,
which is up 2.3% from a year earlier. Although it is
following an increasing trend, we are noticing a pattern of
seasonal employment spikes in the numbers, and
employment in Rohnert Park has not regained its maximum
from 2008. The total number of business establishments in
2015 in Rohnert Park is 1,555. Sonoma County has about
25,800 business establishments.
About 52% of Rohnert Park’s employed population is in the
category of Services, which includes education, health care,
tourism and legal services. The second largest sector is
Retail Trade. This is very similar to the county average,
though there is a higher prevalence of Services and Retail
Trade in Rohnert Park, while the county has higher
percentages of agriculture and manufacture. Rohnert Park
also supports Sonoma State University (SSU). The campus is
214 acre that supports 7,000 full time equivalent (FTE)
students and 1,200 employees, making it one of the largest
employers in the area. In the future SSU looks to extend its
capacity to support up to 10,000 FTE students.
Figure 2.14: Rohnert Park Unemployment
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Critical Facilities
The LHMP Team identified a number of critical facilities for study and incorporation into the hazard vulnerability and risk analysis.
Because of the confidential nature of some facilities (like water pumps), they are not included in the table below. Damage to these
facilities has the potential to impact the quality of life of residents and to impair the response and recovery from disaster events.
In addition to City-owned properties, several other facilities that provide important services to the city were included. These include,
medical facilities, schools, and mobile home parks.
Table 3.1: Facility Address Facility Type
City Properties
City Hall 130 Avram Avenue Government Center
Corporation Yard (Public Works) 600 Enterprise Drive Public Works
Senior Center 6800 Hunter Drive Community
Community Center 5401 Snyder Lane Community
Burton Avenue Recreation Center 7421 Burton Avenue Community
Spreckels Performing Arts Center 5409 Snyder Lane Community
Callinan Recreation Center 5405 Snyder Lane Community
Animal Shelter 301 J Rogers Lane Community
Pump Facility 201 J Rogers Lane Public Works
Public Safety Facility (Main) 500 City Center Drive Government Center
Fire Station 2 (North) 5200 Country Club Drive Fire
Fire Station 3 (West) (Future) 5870 Labath Avenue Fire
Fire Station 4 (South) 1312 Maurice Avenue Fire
State Farm Expressway Landscaping State Farm Expressway Public Works
Enterprise Avenue Landscaping Enterprise Avenue Public Works
Water Tanks Various Locations Public Works
Parks
Alicia Park 300 Arlen Drive Park
Benicia Park 7471 Bernice Avenue Pool
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Table 3.1: Facility Address Facility Type
Benicia Pool 7421 Burton Avenue Park
Caterpillar Park 7430 Circle Drive Park
Colegio Vista 1200 Southwest Boulevard Park
Dorotea Park 895 Santa Dorotea Park Park
Eagle Park 1115 Emily Avenue Park
Gold Ridge Park 1455 Golf Course Drive Park
Golis Park 1450 Golf Course Drive Park
Honeybee Park 1170 Golf Course Drive Park
Honeybee Pool 1170 Golf Course Drive Pool
Ladybug Park 8517 Liman Way Park
Magnolia Park 1401 Middlebrook Park
Magnolia Pool 1501 Middlebrook Way Pool
Oak Grove Park (Future) Keiser Avenue Park
Rainbow Park 1345 Rosana Way Park
Sunrise Park 5201 Snyder Lane Park
Twin Creeks Park Kerry Road Park
Willow Glen Park (Future) Bodway Parkway Park
Robert's Lake 5010 Robert's Lake Road Park
Rohnert Bark (Dog Park) 5010 Robert's Lake Road Park
Field of Friends (Dog Park) 7471 Bernice Avenue Park
Creekside Multi-Use Paths N/A Multi-Use Paths
Municipal Golf Course (North) 100 Golf Course Drive Park
Municipal Golf Course (South) 100 Golf Course Drive Park
Non-City Facilities
California Highway Patrol 6100 Labath Avenue State
SMART Station N/A (Rohnert Park Expressway) Transportation
Sutter Pacific 1400 Medical Center Drive Medical
Kaiser Permanente 5900 State Farm Drive Medical
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Table 3.1: Facility Address Facility Type
Rohnert Park Cancer Center 301 Professional Center Drive Medical
Schools
Marguerite Hahn Elementary 825 Hudis Street School
Evergreen Elementary 1125 Emily Avenue School
Technology Middle School 7165 Burton Avenue School
Rancho Cotate High School 5450 Snyder Lane School
Monte Vista Elementary 1400 Magnolia Avenue School
Lawrence E. Jones Middle School 5154 Snyder Lane School
Richard Crane Elementary 1290 Southwest Boulevard School
John Reed Elementary 390 Arlen Drive School
Waldo Rohnert Elementary 550 Bonnie Avenue School
Technology High School 1801 East Cotati Avenue School
La Fiesta Elementary 8511 Liman Way School
Sonoma State University 1801 East Cotati Avenue University
Credo High School 1300 Valley House Drive School
Mobile Home/RV Parks
Rancho Verde 650 Rohnert Park Expressway Mobile Home Park
Rancho Grande 5099 Snyder Lane Mobile Home Park
Rancho Feliz 6607 Redwood Drive Mobile Home Park
Valley Village 6401 Country Club Drive Mobile Home Park
Las Casitas 7545 Bridget Drive Mobile Home Park
Wine Country RV Park 7450 Cristobal Way RV Park
Table 3.2: Parks, Recreation Facilities, and Open Space Acres Total per 1,000 residents
Neighborhood, Community, and Mini-Parks 116 2.9
Golf Courses 310 7.8
Other Recreational Facilities 47.5 1.1
TOTAL 473.5 10.9
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Table 3.3: Infrastructure
Roads 130 miles
Rail 4 miles
Bridges and Overpasses 20 (total)
Other Infrastructure
The City of Rohnert Park has the typical types of buildings, water and power systems of a community that experienced the majority of
its growth between 1980 and 1999. A brief description follows:
Buildings – Rohnert Park does not have a historic central business district. The majority of the city’s structures are single-family, one-
story homes built from wood built after 1960. Rohnert Park has no unreinforced masonry buildings. A, B, and C Sections of the city
are most at risk because they are the oldest; A Section being built between 1958-1962, B Section from 1963-1965, and C Section from
1977-1980.
Water – The City of Rohnert Park currently derives its drinking-water supply from a well field consisting of 42 municipal supply
wells, 31 of which were active in 1999; and eight active connections to the Sonoma County Water Agency (SCWA) Petaluma
Aqueduct, which supplies water from the Russian River. The Sonoma County Water Agency operates and maintains a water
transmission system authorized by the Agreement for Water Supply and Construction of Russian River-Cotati Intertie Project. Parties
to the Agreement are the Agency and eight public entities, including Rohnert Park. The total amount of water pumped from the 31
operational wells in 1999 was approximately 1.5 billion gallons. Agricultural users in the vicinity of Rohnert Park use a combination
of private well water and reclaimed water for irrigation. Canon Manor residences use both shared and individual wells as their water
supply.
Sewer – All development within the 1999 City limits was connected to sewer service as of 1999. The City also provides sewer service
to the Sonoma State University (SSU) campus, located east of the 1999 City limits. Residential development in Canon Manor, located
outside the 1999 City limits but within its sphere of influence, is served by septic systems, not City sewers. Sewer mains collect
wastewater and transport it to the Rohnert Park Pumping Station. As of 1999, the wastewater mains were adequate in size to serve the
area within the 1999 City limits. A 24-inch interceptor sewer main extends westward from the pumping station to the treatment plant.
Power - the only significant generating plant in the County is the Geyser’s Project. The largest geothermal plant in the world, the
Geysers produces 25% of the county’s non-hydro green electricity.
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Evacuation Routes
US Highway 101 is the primary evacuation route from Rohnert Park. The highway is primarily a north-south route. Other evacuation
routes include Petaluma Hill Road on the east side of town, Stony Point Road on the west side of town, Crane Creek Road, leading to
Bennett Valley on the east, and Highway 116 leading west (via Cotati) towards Sebastopol.
Figure 3.1: Map of Rohnert Park Transportation
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Figure 3.2: Critical Facilities
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HAZARD IDENTIFICATION, ANALYSIS AND ASSESSMENT
Hazards are risks that Rohnert Park wants to identify in order to determine the
potential impacts to people, economy, and the built and natural environments of
the community. Identifying hazards is just one step in the planning process, but
provides the foundation for the rest of the mitigation planning process, which
focus on identifying and prioritizing actions to reduce risk to hazards.
Rohnert Park wants to be prepared in emergency situations by being resilient
which will minimize the risk for loss of community livelihood and assets.
Rohnert Park looks to FEMA’s definition of risk which states: “the potential for
damage, loss, or other impacts created by the interaction of natural hazards with
community assets (5-1).” Natural hazards, risk, and community are inevitably
connected. It is up to the City to be as prepared as possible to make sure risk is
minimalized, overall making it easier for the City to respond. The image below from
FEMA illustrates the concept of risk as the relationship between hazards and community. Risk is overlapping both, but the LHMP will
help identify key information such as Rohnert Park’s own geographic environment, and the hazards associated with that. This
awareness closes the overlap of risk making Rohnert Park more resilient.
Using FEMA’s hazard mitigation planning resources as guidance, the Rohnert Park LHMP team analyzed the relevance of a
comprehensive list of natural hazards in Rohnert Park. The team used the 2012 Emergency Management Plan as a start to identify the
risks and hazards that were most pertinent to the City.
FEMA Element B: Hazard Identification and Risk Assessment
• B1. Does the Plan include a description of the type, location, and extent of all natural hazards that can affect each jurisdiction?
44 CFR 201.6(c)(2)(i) and 44 CFR 201.6(c)(2)(iii)
• B2. Does the Plan include information on previous occurrences of hazard events and on the probability of future hazard events
for each jurisdiction? 44 CFR 201.6(c)(2)(i)
• B3. Is there a description of each identified hazard’s impact on the community as well as an overall summary of the community’s
vulnerability for each jurisdiction? 44 CFR 201.6(c)(2)(ii)
• B4. Does the Plan address NFIP insured structures within each jurisdiction that have been repetitively damaged by floods? 44
CFR 201.6(c)(2)(ii)
Figure 3.3: Risk Assessment
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FEMA has identified 21 unique hazards that it recommends for evaluation and inclusion in a hazard mitigation plan. Several of these
hazards are not applicable to Rohnert Park. Because of past events, communities may also include other hazards not included on
FEMA’s list. The Planning Team evaluated a list of hazards, including those recommended by FEMA and determined which hazards
should and should no t be included in the Plan. Table 3.4 shows the hazards that the LHMP Team evaluated.
Table 3.4: Evaluated Hazards for Rohnert Park LHMP
Hazard Decision Explanation
Avalanche Exclude Rohnert Park is not near mountainous areas where avalanches occur.
Climate Change Include (as factor) Climate change is not stand-alone but affects many other hazards.
Coastal Erosion Exclude Rohnert Park is not a coastal community.
Coastal Storm/Storm Surge Exclude Rohnert Park is not a coastal community.
Dam Failure Include Small portions of Rohnert Park lie within a dam failure inundation zone.
Disease and Pests Exclude These are not considered a sufficiently high threat to the City.
Drought Include Rohnert Park has been affected by severe droughts in the past.
Earthquakes/Liquefaction Include Rohnert Park lies in an area affected by earthquakes in the past.
Erosion/Expansive Soils Exclude Neither are a concern for the City of Rohnert Park.
Extreme Cold and Heat Exclude These are not a concern for the City, although heat may be in the future.
Fault Rupture Include Although not in a fault rupture zone, one is in proximity to the City.
Flood Include Flood zones are present in Rohnert Park.
Hailstorms Exclude Hailstorms are not an issue of concern in Rohnert Park.
Hazardous Materials Include Included, although generally not an issue of concern in Rohnert Park.
Human Caused Hazards Exclude There are no human caused hazards that merit inclusion in Rohnert Park.
Hurricane/Lightning/Wind Exclude Rohnert Park is not affected by hurricanes or other severe storms.
Land Subsidence Exclude This is not a hazard of concern in Rohnert Park.
Landslide Include There is some minor risk of landslides in outlying areas of Rohnert Park.
Sea Level Rise Exclude Rohnert Park is not a coastal community.
Severe Winter Storms Exclude Refers to blizzards and ice storms; not a concern for Rohnert Park.
Tornado Exclude Tornados are not a hazard of concern for Rohnert Park.
Tsunami Exclude Rohnert Park is not a coastal community.
Volcano Exclude There are no known volcanoes near Rohnert Park.
Wildfire Include There are areas of elevated fire risk in and adjacent to Rohnert Park.
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Hazard Prioritization
FEMA guidance recommends that the Planning Team prioritize hazards using four individual criteria. The four criteria are as follows:
• Probability: the likelihood of the hazard occurring in the future in the community
• Location: the size of the affected area in the community if the hazard occurs
• Maximum probable extent: the severity of the direct damage to the community from the hazard
• Secondary impacts: the severity of indirect damages to the community from the hazard (e.g., the loss of water service a s a
consequence of damage to infrastructure)
For each criterion, the Planning Team assigned a score of 1 to 4, consistent with FEMA guidance. The Planning Team then assigned a
weighting factor to each criterion, using values recommended by FEMA, with more important criteria receiving a higher weighing
factor. Table 3.5 shows the FEMA recommended rubric used by the Planning Team for this prioritization.
Table 3.5: Hazard Criteria Ranking Scores and Weighing Factors
Probability Maximum Possible Extent
Based on estimated likelihood of
occurrence from historical date
Weighing Factor: 2.0 Based on percentage of damage to
typical facility in community
Weighing Factor: 0.7
Probability Score Impact Score
Unlikely 1 Weak – little to no damage 1
Occasional 2 Moderate – some moderate damage 2
Likely 3 Severe – devastating damage 3
Highly Likely 4 Extreme – catastrophic damage 4
Location Secondary Impacts
Based on size of geographical area of
community affected by hazard
Weighing Factor: 0.8 Based on estimated secondary impacts
to community at large
Weighing Factor: 0.5
Affected Area Score Impact Score
Negligible 1 Negligible – no loss of function 1
Limited 2 Limited – minimal loss of function 2
Significant 3 Moderate – some loss of function 3
Extensive 4 High – major loss of function 4
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Threat Level for Included Hazards
The LHMP Team combined the assigned value of 1 to 4 for each criterion with its weighing factor to determine an overall score for
each criterion. In accordance with FEMA guidance the team then summed the scores for location, maximum probable extent, and
secondary impacts to calculate the total impact score for each hazard. Lastly, the LHMP Team multiplied the impact score by the
probability score to arrive at a total score for each hazard. A total score of 0 to 12 is considered a low-threat hazard, a score of 12.1 to
42 is considered a high-threat hazard. Table 3.6 shows the criterion scores, total scores, and threat levels for all hazards in the Plan.
Table 3.6: Scores and Threat Levels for Included Hazards
Hazard Probability Location Primary Impact Secondary Impact Total Score Threat Level
Dam Failure 1 1 1 1 4.2 Low
Drought 4 4 3 3 54.4 High
Earthquake 4 4 4 4 64.0 High
Fault Rupture 2 1 1 2 6.5 Low
Flood 3 2 3 3 31.2 Medium
Hazardous Materials 1 1 1 1 4.2 Low
Landslide 1 1 1 1 4.2 Low
Liquefaction 1 2 1 1 5.6 Low
Wildfire/WUI-Fire 3 4 3 3 40.8 Medium
Based on this scoring and calculation, drought and earthquake come in with the highest threat level, with flood and wildfire at a
medium threat level. All other hazards analyzed in this Plan are at a low threat level.
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Future Risk Matrix
In order to rank potential future hazards in Rohnert Park, Table 3.7 will be used to show the probability in years that a hazard will
occur again. Each hazard will be ranked on a scale of one to five. One being the lowest future risk, possibly occurring once every 50
years. Five being the highest future risk, possibly occurring within the next five years. These scores not definitive timelines for future,
in example; Earthquakes are a risk level of five in Rohnert Park, but that does not mean a major earthquake will occur every five
years. They are based on previous occurrences and the hazard prioritization section.
Table 3.7: Future Risk Potential
Risk Level Future Probability
One Very Low Occurrence Probability: 50yrs at the most
Two Low Occurrence Probability: 20-40 years
Three Medium Risk Probability: 10-20 years
Four High Occurrence Probability: 5-10 years
Five Very High Occurrence Probability: Every 5-yrs
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Earthquakes
Hazard Description
Earthquakes happen when two tectonic plates slip past
each other beneath the earth’s surface. At the surface, the
location of this slip is called a fault. As the plates slide
past each other, the stresses between them tend to cause a
buildup of energy that when released causes an
earthquake. The stored energy from this process is
released as seismic waves, causing ground shaking in the
area around the slip. The deformation of plates and
accumulated stress from this process creates faults in a
wider area around the plate boundary, meaning that
earthquakes can happen in areas outside of the plate
boundary itself.
Earthquakes vary in size and intensity with a range of
potential impacts. The amount of damage from an
earthquake is determined not only by the duration and
intensity of ground shaking but also by the conditions in
the impacted area, including soil conditions, construction
quality, distance from the center of the earthquake, and the
type of fault rupture. This hazard profile covers fault
rupture, ground shaking, and liquefaction, the most common impacts from an earthquake. When a fault ruptures this is the actual
movement and displacement of the ground’s surface along the fault boundary which is considered the earthquake. Depending on the
type of fault, this displacement may be horizontal, vertical, or both. Damage from fault rupture can be severe depending on the size of
the displacement, but is limited to the relatively small area along the fault boundary where the slip occurred. Not all earthquakes result
in fault rupture that is visible at the surface, and strong earthquakes can occur without any discernible displacement along the
boundary.
Hazard Location and extent
The City of Rohnert Park is just one out of 97 cities within the Bay Area that are within 10 miles of an active fault. Rohnert Park is in
the vicinity of several known active and potentially active earthquake faults including the San Andreas and Healdsburg/Rodgers Creek
Figure 3.4: Earthquake Intensity Scale
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and the Hayward fault. The City of Santa Rosa is 8 miles to the north of Rohnert Park and has the Rodgers Creek fault running north-
south through the center of the City of Santa Rosa. This does pose a high risk of seismic activity in the greater Santa Rosa area.
A major earthquake occurring in or near this jurisdiction may cause many deaths and casualties, extensive property damage, fires,
hazardous material spills and other ensuing hazards. The Rodgers Creek fault is considered the greatest earthquake threat to Sonoma
County because of the high probability of rupture and its proximity to the County’s greatest concentration of population, governmental
services and infrastructure. The effects could be aggravated by aftershocks and by the secondary effects of fire, hazardous
material/chemical accidents and possible failure of waterways and dams. The time of day and season of the year would have a
profound effect on the number of dead and injured. Such an earthquake would be catastrophic in its effect upon the population and
could exceed the response capabilities of the City of Rohnert Park, the Sonoma County Op Area and the Governor’s Office of
Emergency Services and other state agencies. Damage control and disaster relief support would be required from other local
governmental and pr ivate organizations, and from the state and federal governments.
Hazard Vulnerability and Risk Assessment
Ground shaking: The most significant earthquake action in terms of potential structural damage and loss of life is ground shaking.
Ground shaking is the movement of the earth's surface in response to a seismic event. Ground shaking impacts can lead to surface
rupture, liquefaction, landslides, and infrastructure failures, which could lead to fires and other secondary hazards. The geology of the
impacted area alters the amount of ground shaking felt. Thick, water-saturated, unconsolidated materials will generally experience
greater shaking motion than areas of firm bedrock.
The size and magnitude of an earthquake have different ways of being measured. The magnitude of the earthquake, distance from the
epicenter, and characteristics of surface geology determine the intensit y of the ground shaking and the resultant damages. The
magnitude is a number that characterizes the relative size of an earthquake. Magnitude is based on measurement of the maximum
motion recorded by a seismograph. Many scales, such as the Richter scale, do not provide accurate estimates for the magnitudes of
large earthquakes. To account for these large earthquakes, the moment magnitude scale (abbreviated as MMS; denoted as MW or M)
is preferred for its ability to cover a wide range of earthquake sizes and be applied globally. The moment magnitude scale is based on
the total moment release of the earthquake. Moment magnitude is a product of the distance a fault moved and the force required to
move it. It is derived from modeling recordings of the earthquake at multiple stations. The Modified Mercalli Intensity Scale for
Earthquakes shown in the Table below measures ground shaking intensity in terms of perception and damage and takes into account
localized earthquake effects. The amount of shaking experienced at different locations varies based not only on the overall magnitude
but also on the distance from the fault that ruptured in the earthquake, geologic conditions, and the level of preparedness built into
surrounding infrastructure. This hazard is the primary cause of the collapse of buildings and other structures
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Hazard History
The Bay Area has experienced significant, well-documented earthquakes.
Since 1855, more than 140 earthquakes have been felt in the Santa Rosa area.
Although earthquake records prior to the year 1900 are difficult to interpret,
seven earthquakes are believed to have caused damage to structures in Sonoma
County during the 19th century. Two earthquakes are of note: the 1868 M7.2
earthquake on the Hayward Fault, and the 1898 M6.7 earthquake believed to
have occurred on the Rodgers Creek Fault. Although damage from these two
events was limited due to the area’s sparse population at the time, a recurrence
of either of these events could result in significant damage to today’s
widespread and varied infrastructure and building stock. The April 18, 1906,
M8.3 earthquake on the northern segment of the San Andreas Fault, known for
devastating San Francisco, caused major damage in Santa Rosa, Sebastopol,
Healdsburg, Petaluma and other communities. Santa Rosa, only 20 miles from
the San Andreas Fault, is said to have suffered more damage proportionally to
its size than any other Bay Area city.
Liquefaction: Many areas may have buildings destroyed or unusable due to the phenomenon of liquefaction. Liquefaction is the loss
of shear strength of a soil. The shear strength loss results from the increase of water pressure caused by the rearrangement of soil
particles induced by shaking or vibration. Liquefaction has been observed in many earthquakes, usually in soft, poorly graded granular
materials (i.e., loose sands), with high water tables. Liquefaction usually occurs in the soil during or shortly after a large earthquake.
In effect, the liquefaction soil strata behave as a heavy fluid. Buried tanks may float to the surface and objects above the liquefaction
strata may sink. Pipelines passing through liquefaction materials typically sustain a relatively large number of breaks in an earthquake
(Rohnert Park Emergency Management Plan).
Extent
Rohnert Park is located near the Rogers Creek and Hayward Fault. If one of these fault lines were to set off an earthquake, Rohnert
Park is at a medium risk of liquefaction. This is because Rohnert Park soil is made up of clays which are not susceptible to
liquefaction. But, there are multiple creeks (Hinebaugh, Copeland, and Crane) that run through Rohnert Park. These streams carry
sands, silts, and gravel which are more susceptible to liquefaction. Development located near these streams could expect to see a much
higher risk of liquefaction.
Figure 3.5: 2014 Napa Earthquake
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The 1969 Rodgers Creek / Healdsburg Fault Earthquake was the last major earthquake to occur in the Sonoma County area on
October 1, 1969. Two earthquakes of Magnitudes 5.6 and 5.7 originated near the juncture of the Rodgers Creek and Healdsburg Fault,
approximately two miles north of Santa Rosa. Total building damage was estimated at $6 million, with dwelling contents losses at
$1.25 million. Several County buildings suffered damage, including the Library, Post Office, and Veterans Memorial Building. There
was more than expected damage to the newly constructed two-story Sonoma County Social Services Building at the County
Administration Center. The 1989 Loma Prieta Earthquake, 6.9 magnitude earthquake was caused by a slip along the San Andreas
Fault. Though the damage in Sonoma County from the quake was very minor, the quake killed 63 people and injured 3,757 throughout
Northern California. It caused a total of over 16,700 housing units to be uninhabitable throughout the Monterey and San Francisco
Bay Areas and left some 3,000-12,000 people homeless. The most recent earthquake in this area, the 2014 Napa Quake, was felt
throughout Sonoma County and in Rohnert Park and cause millions of dollars of damage in neighboring Napa County.
Risk of Future Occurrences
A major earthquake occurring in or near this jurisdiction may cause many deaths and casualties, extensive property damage, fires,
hazardous material spills and other ensuing hazards. The Rodgers Creek fault is considered the greatest earthquake threat to Sonoma
County because of the high probability of rupture and its proximity to the County’s greatest concentration of population, governmental
services and infrastructure. The effects could be aggravated by aftershocks and by the secondary effects of fire, hazardous
material/chemical accidents and possible failure of waterways and dams. The time of day and season of the year would have a
profound effect on the number of dead and injured. Such an earthquake would be catastrophic in its effect upon the population and
could exceed the response capabilities of the City of Rohnert Park, the Sonoma County Op Area and the Governor’s Office of
Emergency Services and other state agencies. Damage control and disaster relief support would be required from other local
governmental and private organizations, and from the state and federal governments.
Extensive search and rescue operations may be required to assist trapped or injured persons. Injured or displaced persons could require
emergency medical care, food and temporary shelter. Identification and burial of many dead persons would pose difficult problems;
public health would be a major concern. Mass evacuation may be essential to save lives, particularly in areas downwind from
hazardous material releases. Many families would be separated particularly if the earthquake should occur during working hours, and
a personal inquiry or locator system could be essential to maintain morale. Emergency operations could be seriously hampered by the
loss of communications and damage to transportation routes within, and to and from, the disaster area and by the disruption of public
utilities and services.
The economic impact on the City of Rohnert Park from a major earthquake would be considerable in terms of loss of employment and
loss of tax base. Also, a major earthquake could cause serious damage and/or outage of computer facilities. The loss of such facilities
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could curtail or seriously disrupt the operations of banks, insurance companies and other elements of the financial community. In turn,
this could affect the ability of local government, business and the population to make payments and purchases.
Based on table 3.7, earthquakes have a risk probability of five within Rohnert Park. Previous occurrences and Rohnert Park’s location
make it a very high risk of probability. Future occurrences of liquefaction will only occur if there is an earthquake. Based on the high
risk of earthquakes in the area, liquefaction risk is related and will also be a probability of five. Figure 3.7 shows the risk of
occurrence if an earthquake is to occur.
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Figure 3.6: Probability of Earthquake Intensity (Shaking)
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Figure 3.7: Potential Liquefaction
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According to the USGS, there is a 31% chance of a major earthquake along the Rogers Creek fault by 2038 and a 93% probability of a
magnitude 6.7 or greater in Northern California by 2038.
Climate Change Considerations
Seismic events are not directly impacted by climate change. It is uncertain the likelihood, size and severity of seismic events. Since the
field of climate change science is dynamic, the City will continue to review and summarize new research that occurs on this topic
during the next update cycle.
Flooding
Hazard Description
Flooding is a temporary condition in which land that is normally dry is partially or completely inundated. Flooding occurs when water
bodies, such as streams, rivers, lakes, or reservoirs, are abnormally high and overflow into adjacent low-lying areas. These areas are
known as floodplains, defined by their exposure to risk of recurring floods. Given Rohnert Park’s inland location the City is protected
from coastal flooding which is associated with high tides and coinciding strong winds. Flooding within the City’s planning area are a
result of heavy rains in low-lying areas with limited drainage routs and along creeks that are prone to flooding in 100-year storm
events. Floods can be powerful enough to move large objects swiftly into other objects, cause damage to buildings and infrastructure,
and weaken foundations and soils. Secondary impacts of flooding, including saturated soils and erosion from flooding events can
cause trees to weaken and collapse, increasing the potential for property damage and loss of life. Taken from the City’s Emergency
Management Plan it is stated that floods are generally classed as either slow-rise or flash floods. Slow-rise floods may be preceded by
a warning time lasting from hours to days or possibly weeks. Evacuation and sandbagging for a slow-rise flood may lessen flood-
related damage. Conversely, flash floods are the most difficult to prepare for, due to the extremely short warning time, if any is given
at all. Flash flood warnings usually require immediate evacuation within the hour. Within Sonoma County floods are the most
frequent natural hazard, and causing the greatest amount of property losses. Within the state, floods are second most common types of
disaster, fires being the first.
Before Rohnert Park was developed, mo st rainfall fell onto natural areas. The water soaked into the ground until it reached a
saturation point, at which time it traveled, sometimes below the surface of the soil, sometimes in above-ground swales, via sheet flow,
to the nearest creek or water body. With urban development of the area, impervious surfaces were created. An impervious surface can
be a constructed surface -- like paved roads, parking lots and rooftops -- or a natural surface compacted in some way so that the
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infiltration of surface water is impacted or prevented. Rain falling on impervious surfaces creates runoff that is sent through our storm
water system of street gutters and storm drains, quickly to the nearest creek and downstream.
While our conventional storm water system of gutters, pipes and channels has done its job to protect properties and lives here in this
urbanized area, it also has had replaced some of the beneficial functions of natural surfaces that protect environments and populated
areas downstream, such as lessening the peak storm water level, slowing the velocity of water through the waterbodies, providing
infiltration to groundwater, and filtering out pollutants. The City’s Public Works Department maintains the City-owned portions of the
storm water system, including gutters, inlets, catch basins, pipes and outfalls.
The Sonoma County Water Agency (SCWA) manages most of the flood control channels that course through Rohnert Park. The
channels in Rohnert Park are included in "Zone 1A" (Laguna de Santa Rosa - Mark West Creek watershed), one of nine geographical
zones encompassing a major watershed. These flood control zones were established in 1958 as a means of financing the construction
and maintenance of flood protection works within Sonoma County. SCWA either owns in fee the rights-of-way for constructed flood
control channels, or holds easements on them for maintenance. Maintenance of flood control channels and creek beds are under
contractual agreement with Sonoma County Water Agency.
Hazard Location and extent
Areas in Rohnert Park are flood prone in heavy rains. This can be visualized on the Rohnert Park 2015 Flood Areas Map. There are
several major creeks that intersect with Rohnert Park and could potentially cause flooding within the 100-500 year flood plain and
general low-lying areas. The creeks identified on the map are Wilfred Bellvue Channel, Coleman Creek, Five Creek, Crane Creek,
Hinebaugh Creek, Copeland Creek, and Laguna De Santa Rosa. A large area in the Northwest corner of the City right outside city
limits is prone to flooding, that looks to span 1 square mile in area where the Laguna De Santa Rosa, Hinebaugh Creek and Wilfred
Bellvue channel intersect. Area 1 on the map is adjacent to this area inside the city limits and is designated as Rancho Verde Mobile
Home Park and is lining with Hinebaugh Creek. The Streets across the Hinebaugh creek near Labath Ave are prone to flooding as
well. Areas lining the major creeks such as Copeland Creek on Avram Avenue when City Hall is located is prone to flooding. In the
Northeast corner of the City where the Rohnert Park Municipal Golf Course is located including some streets of the neighboring
residential are prone to flooding during the rainy seasons as Coleman Creek may overflow. Other areas designated on the map have
sporadic locations of low-lying flood prone areas during the rainy season.
Hazard History
Flooding has had a serious impact on the county as a whole in the past. The most recent occurrence was in the winter of 2005-2006
when rainfall measured in the City of Santa Rosa at 17.6 inches (NOAA 2013). The President declared this flood a major disaster, and
more than 100 roadways were blocked due to flooding or landslides. Some 2,100 business and residential properties were inundated
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and 50,000 residents were without power (NOAA 2013). Sonoma County business and residential damages were estimated at $104
million (NOAA 2013). The City was impacted by the 2005/2006 Winter Storms. General impacts from the winter storms were
flooding and power outages. Public works crews assessed the flooded areas and were able to clean out blocked drainage trash gates,
removed debris from ditches and culverts and placed flooded, road closed ahead, and road closed signs, as needed, on flooded road
sections to warn the public of flooded areas. Public works has some provisions for sandbags – primarily available only to areas where
living space would be flooded or impacted. In areas where trees fell in the roadway, the trees were moved out of the roadway and
when the storm cleared the trees were cut up and removed. Vehicles, properties and buildings sustained damage from flood waters
particularly on Martin Avenue and Heartwood Court.
Hazard Vulnerability and Risk Assessment
The most readily available source of information regarding the 100-year flood is the Flood Insurance Rate Maps (FIRMs) prepared by
FEMA to support the National Flood Insurance Program (NFIP). The standard for floodplain management in the United States is to
delineate and address flood risks within the area inundated by the 100-year flood or base flood. Floods may be quantified in terms of
flow (cubic feet per second (CFS), water elevation, inundated area, and reoccurrence interval. For instance, a 100-year flood has a 1‐
percent chance of occurring in any given year. Although the recurrence level is based on statistical averages, the actual occurrence of
events varies and could occur at shorter intervals or even within the same year.
Mobile Home Susceptibility
Statewide, the 1996 floods destroyed 156 housing units. Of those units, 61 % were mobile homes and trailers. Many older
manufactured home parks are located in floodplain areas. Mobile homes have a lower level of structural stability than stick-built
homes, and must be anchored to provide additional structural stability during flood events. Because of confusion in the late 1980s
resulting from multiple changes in NFIP regulations, there are some communities that do not actively enforce anchoring requirements.
Lack of enforcement of manufactured home construction standards in floodplains can contribute to severe damages from flood events.
The City of Rohnert Park has participated in the National Flood Insurance Program since 1981. The City does not participate in the
Community Rating System. Staff antic ipates seeking City Council direction for participation in the Community Rating System. The
City started participation in the NFIP on June 1, 1981. An update, effective December 2, 2008, was released which reflected the
current requirements of the NFIP for non-coastal communities. In addition to using FEMA maps to regulate flood hazard areas, the
City may require elevation certificates at the building permit stage to verify compliance with NFIP requirements. There are no repeat
loss properties within the C ity of Rohnert Park.
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Identification of Flood Areas
Flood maps and Flood Insurance Studies (FIS) are often used to identify flood-prone areas. The NFIP was established in 1968 as a
means of providing low-cost flood insurance to the nation’s flood-prone communities. The NFIP also reduces flood losses through
regulations that focus on building codes and sound floodplain management. NFIP regulations (44 Code of Federal Regulations (CFR)
Chapter 1, Section 60, 3) require that all new construction in floodplains must be elevated at or above base flood level. Flood
Insurance Rate Maps (FIRM) and Flood Insurance Studies (FIS) Floodplain maps are the basis for implementing floodplain
regulations and for delineating flood insurance purchase requirements.
A Flood Insurance Rate Map (FIRM) is the official map produced by FEMA which delineates SFHA in communities where NFIP
regulations apply. FIRMs are also used by insurance agents and mortgage lenders to determine if flood insurance is required and what
insurance rates should apply. Water surface elevations are combined with topographic data to develop FIRMs. FIRMs illustrate areas
that would be inundated during a 100-year flood, floodway areas, and elevations marking the 100-year -flood level. In some cases, they
also include base flood elevations (BFEs) and areas located within the 500-year floodplain. Flood Insurance Studies and FIRMs
produced for the NFIP provide assessments of the probability of flooding at a given location. FEMA conducted many Flood Insurance
Studies in the late 1970s and early 1980s. These studies and maps represent flood risk at the point in time when FEMA complet ed the
studies. However, it is important to note that not all 100-year or 500-year floodplains have been mapped by FEMA.
FEMA flood maps are not entirely accurate. These studies and maps represent flood risk at the point in time when FEMA completed
the studies, and does not incorporate planning for floodplain changes in the future due to new development. Although FEMA is
considering changing that policy, it is optional for local communities. Man-made and natural changes to the environment have
changed the dynamics of storm water run-off since then.
Although many communities rely exclusively on FIRMs to characterize the risk of flooding in their area, there are some flood-prone
areas that are not mapped but remain susceptible to flooding. These areas include locations next to small creeks, local drainage areas,
and areas susceptible to manmade flooding. Communities find it particularly useful to overlay flood hazard areas on tax assessment
parcel maps. This allows a community to evaluate the flood hazard risk for a specific parcel during review of a development request.
Coordination between FEMA and local planning jurisdictions is the key to making a strong connection with GIS technology for the
purpose of flood hazard mapping.
Risk of Future Occurrences
Based on previous occurrences, the City of Rohnert Park should expect a flooding risk of five in the future. Areas that are prone to
flooding are near Copeland Creek and Hinebaugh creek which have been channelized. This causes water to move quicker and build up
rapidly in the event of a storm. As well, areas on the west side of Rohnert Park are at risk due to the Laguna De Santa Rosa floodplain.
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Figure 3.7: Known Flooding from 2005 Flood Event with Mobile Home Parks
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Figure 3.8: Known Flooding from 2005 Flood Event with Critical Facilities
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Figure 3.9: FEMA Flood Hazard Areas with Critical Facilities
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Figure 3.10: FEMA Flood Hazard Areas with Mobile Home Parks
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Impact of Development
When structures or fill are placed in the floodway or floodplain water is displaced. Development raises the river levels by forcing the
river to compensate for the flow space obstructed by the inserted structures and/or fill. When structures or materials are added to the
floodway or floodplain and no fill is removed to compensate, serious problems can arise. Flood waters may be forced away from
historic floodplain areas. As a result, other existing floodplain areas may experience flood waters that rise above historic levels. Local
governments must require engineer certification to ensure that proposed developments will not adversely affect the flood carrying
capacity of the Special Flood Hazard Area (SFHA).
Displacement of only a few inches of water can mean the difference between no structural damage occurring in a given flood event,
and the inundation of many homes, businesses, and other facilities. Careful attention should be given to development that occurs
within the floodway to ensure that structures are prepared to withstand base flood events. In highly urbanized areas, increased paving
can lead to an increase in volume and velocity of runoff after a rainfall event, exacerbating the potential flood hazards. Care should be
taken in the development and implementation of storm water management systems to ensure that these runoff waters are dealt with
effectively.
Climate Change Considerations
Scientific evidence involving climate change include more variation in weather patterns for Sonoma County. Overall there are
significant challenges for planning around water supply and flood control. Sonoma County’s wintertime precipitation comes mainly in
storms from the Pacific Ocean brought on atmospheric rivers. Between 1948 and 2011, 87% of floods on the Russian River were due
to atmospheric rivers (Dettinger et al., 2011). With the wettest scenarios being considered, Sonoma County including Rohnert Park
could see almost a 25% increase in precipitation compared to historical (20th century) conditions while the driest scenario projects an
approximately 20% decrease (Climate Ready Sonoma County). By the year 2100 Sonoma County will see bigger, more variable
floods that will cause potentiality in 1) physical danger and economic impact for people living in low-lying areas along rivers and bay
lands, especially those without reliable transportation 2) Death from drowning and injuries from flood 3) Public health risks from
damage to sanitation, utility, and irrigation systems 4) Limitations on access to critical services and 5) Economic impact to businesses
in or affected by flooded areas.
With the calculated changes in precipitation due to climate change there will still continue to be some years with precipitation similar
to historic averages as the error bars for all scenarios in Figure 3.14 overlap with the 0% change axis. However, the warm/wet scenario
forecasts some years with an almost 75% increase in mean annual precipitation while the dry scenarios project years with decreases
between 25-50% of historical averages (Climate Ready Sonoma County).
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Drought
Hazard Description
Droughts are an effect of prolonged periods of
little to no rainfall which result in shortages of
water. Droughts develop over an extensive
period of time. A year with abnormally little
precipitation would be considered a dry year.
Multiple dry years may develop drought
conditions, whereas multiple years of suitable
rain or wet years will generally alleviate the
drought. In years of drought the inhabitants do
slowly feel the effects. In urban areas, drought
conditions can cause a decrease in available
water supplies, which may lead to increases in
water rates or restrictions in water use.
Communities may need to seek alternative
water supplies to meet demand, which can be
a costly and lengthy process.
Drought conditions change the landscape,
causing vegetation such as street trees,
landscaped areas in public parks to become
water stressed which can lead to plant disease
or death. Drought conditions harden the
ground, which can lead to increased flooding
when rains return because the soil cannot
easily absorb water. Prolonged drought can
also create increased levels of wildfire risk,
with prolonged conflagrations fueled by excessively dry vegetation. Drought is not localized, but occurs simultaneously across the
region, and may extend statewide or across a larger expanse. For the state droughts have been occurring in prolonged stages that
impact every county, as well as local municipalit ies that are unique in their conditions such as based on local and regional water
Figure 3.11: California Drought as of November 2015
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supply systems, soil conditions, and the typical climate and vegetation land covering. The effects of drought are managed in the Bay
Area through the importation of water and the storage of water in reservoirs.
Hazard History, Location and extent
Droughts are known to reoccur in California.
The State have developed advance strategies
and water infrastructure networks to deal
with water shortages. A drought in one part
of the state may have little to no effect in
another part of the state due to water
resources that are localized. From December
of 2011 to April 2017 California experienced
yet another state-wide drought. In January
2014, the Governor declared a State of
Emergency in California in response to
current drought conditions. To date, 2015 is
the driest recorded year on record in
Califo rnia, with statewide reservoirs at 18–
67% of average (California Governor’s
Office of Emergency Services (2015), as
cited in ABAG 2015). Governor Jerry
Brown ordered a statewide 25%t cut in
urban water use. A year ago, 21% of
California was considered in drought
monitor classification D4, 42%in D3-D4 and
100% of California in D0-D4. As of April
2017 the Governor declared the drought
emergency over. Now that California is
flourishing it will not be the last or the
longest in the years to come. A drought from 1928 to 1937 affected all parts of the state and was the longest drought in California’s
recorded history. Between 1976 and 1977, California experienced one of its most severe droughts, and 1977 was the state’s driest year
on record.
Figure 3.12: California Drought as of October 2018
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Major Droughts that affected the Bay Area, according to ABAG were in 1973, 1976–77, 1987–91, and 2007–09. Drought conditions
in 1973 led to a State-declared disaster in Glenn, San Benito, and Santa Clara counties, resulting in $8 million in agricultural loss.
During the statewide drought of 1976 to 1977, four Bay Area counties (Contra Costa, Napa, San Mateo, and Marin) were among those
where a state disaster was declared. Marin, Solano, and Sonoma counties were affected in the 1987–91 drought, which caused $1.7
billion in crop losses nationwide (Cal OES 2013, as cited by ABAG 2015).
Locally, Sonoma County declared an emergency for drought in February of 2014. A proclamation was adopted calling for water
conservation actions and voluntary water reductions. Rohnert Park adopted Stage 1- voluntary reductions in February 2014. And
subsequently adopted Stage 1-mandatory 20% reductions in August 2014 to comply with the State regulations mandating a statewide
25% reduction target. At the drought’s peak in 2015, approximately 9 percent of Sonoma County was classified as level D3 drought
conditions (extreme drought), with the remainder of the county classified as level D2 (severe drought) which included Rohnert Park.
Risk of Future Occurrences
There are multiple causes for a drought and based on previous droughts, a drought is a risk probability of four and will likely occur in
the next 10 years. A few drivers for drought are: climate change, weather cycles such as El Niño, and large water consumers. Due to
droughts affecting multiple regions, it stresses resources from all around the state.
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Recycled Water System
Rohnert Park’s Recycled Water System provides tertiary treated
recycled water to 31 customers including City parks, two
municipal golf courses, Sonoma State University and several
private commercial properties. The City has been at the
forefront of recycled water use having used recycled water for
over 28 years. In 2015, the City used 310 million gallons on
over 580 acres. The use of recycled water significantly lessens
the potential impacts of droughts on connected properties.
Current development and new city infrastructure is required to
connect to the recycled water system where feasible.
Drought Vulnerability and Future Risk Assessment
Given the historical context and extent to which droughts have
happened so far at each spatial level from the state, county, and
local municipality, droughts are unique among hazards in this
LHMP in that droughts are a more regional disaster meaning
that t he direct impact is the same throughout the City. Unlike
earthquakes, floods, or wildfires where the risk and severity of
impacts vary within the community. As a result, all of Rohnert
Park is in the potential hazard zone for droughts, and no single
area faces higher direct risks. While the severity of any drought
conditions will be consistent across Rohnert Park, the indirect
impacts of a drought can vary depending on residents’
socioeconomic factors. Droughts often lead to more stringent
water use regulations, which can include increased service rates
for households that use higher amounts of water.
Figure 3.13: Rohnert Park recycled Water System
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Climate Change Considerations
Scientific evidence suggests that Sonoma County, and California
overall are expected to experience more very hot days than in the
past, and overall higher temperatures over a longer period of dry
weather. This weather is predicted to create more frequent
droughts and longer droughts. Spring will come earlier and fall
will come later, and these extended periods of hotter, drier weather
will impact regional water supply. The heat will also increase soil
moisture deficit and reduce groundwater recharge. Reduction in
the overall regional water supply due to reduced precipitation
would only exacerbate the local effects of drought (Climate Ready
Sonoma County).
Figure 3.14: Climate Change Precipitation Projections
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Wildfire/Wildland-Urban Interface Fires
Hazard Description
The combination of highly flammable fuel, long dry
summers and steep slopes creates a significant natural
hazard of large wildland fires in many areas of Sonoma
County. A wild land fire is a fire in which the primary fuel is
natural vegetation. Wildland fires can consume thousands
of acres of vegetation, timber and agricultural lands. Fires
ignited in wild land areas can quickly spread, if unabated, to
areas where residential or commercial structures are
intermingled with wild land vegetation. Similarly, fires that
start in urbanized areas can grow into wildland fires. Wild-
land-urban interface fire hazards are especially pronounced
in areas of high structure densities adjacent to undeveloped
open space areas w ith dense vegetation. Wildland-urban
interface fire results in death, injury, economic loss and a
lar ge public investment in firefighting activities.
Wildfire behavior is based on three primary factors:
weather, topography and fuel. Wildland fire season in
Sonoma County spans the months after the last spring rains
have fallen and until the first fall or winter rains occur. The
months of August, September and October have the greatest
potential for wild land fires as vegetation dries out, humidity
levels fall, and off shore winds blow. In Northern California,
Diablo Winds, while rare can occur. These are similar to the
Santa Ana winds founds in Southern California which can drive fires swiftly and unpredictably.
The population of tan oak vegetation in various areas of the County has particular risk due to the rise of Sudden Oak Death Syndrome.
In specific areas, tan oak proliferation and the rapid encroachment of the disease has created an environment of increased vu lnerability
to wildland fire.
Figure 3.15: ABAG WUI Fire Predicted Risk (orange)
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Hazard Location and extent
Wildfires can be caused by natural events, such as lightning or
high winds. However, most wildland fires are human caused.
Campfires, careless smokers, electrical sparks, and arson cause
most wildland and wildland-urban interface fires. In the City of
Rohnert Park and the adjacent rural areas of Sonoma County,
electrical equipment, such as power lines and transformers, has
caused numerous fires. An emerging cause for concern is fires
started by mowing, use of power equipment and other work
around very dry vegetation. Trees growing into power lines
have caused large and damaging fires within the county.
The adjacent hillsides surrounding Rohnert Park are a high-risk
area for wildfires. With off shore winds any such fire, once
started, could blow fire brands and ash into the City of Rohnert
Park.
Hazard Vulnerability and Risk Assessment
The risk of wildland fires in Rohnert Park is generally low
compared to peer cities in Sonoma County. The City has very
little area that would be considered Wildland-Urban Interface. The City’s planned development patterns, relatively compact nature,
and the existence of an urban growth boundary have prevented Rohnert Park from sprawling out in low densities into the surrounding
hillsides where the risk of fire is greater. The existence of agriculture on three sides of the City, as well as the presence of the City of
Cotati to the south, also mitigate the chances of an extreme fire event. Current mitigation activities include abatement of grassland
areas adjacent to and within the City Limits.
Climate Change Considerations
Although Rohnert Park may be considered a low risk area for fires. The surrounding area is all high risk and can cause fires in Rohnert
Park with the right conditions. The probability of future fires is based on weather patterns, brush growth, and human activity.
Changing weather and precipitation patterns as a result of climate change and continuing development, will change the way large fires
originate, grow, and ultimately impact Rohnert Park in the future. Increased precipitation during the rainy season will increase the
growth of grass and brush that will later dry out in the summer, increasing the amount of fuel available for fires. Warmer summers
Figure 3.16: Typical hillside adjacent to Rohnert Park
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will contribute to drier conditions and will place more stress on plants, bushes and trees leaving them vulnerable to pests and disease.
Increasing numbers of trees may die out, subsequently leaving increased amounts of fuel ready to burn.
Risk of Future Occurrences
Wildfires have occurred around Rohnert Park in the past. With climate change considerations and recent more regular occurrences, it
is a risk matrix of five that these events will occur in the future. Areas which have high pot ential for wildfire risk include areas near
city boundaries and WUI zones. The tall grasses that surround the city act as fuel for fires. But, due to Rohnert Park’s urban growth
boundary, the risk can be limited due to prevention of growth into higher risk areas.
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Figure 3.17: Very High
Hazard Severity Zones in
LRA
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Figure 3.18: Historic (Pre-2017) Wildfires near Rohnert Park
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Hazard History and Extent – Table 3.7
Wildfire Year and Name Acreage Burned
1945 – Unknown 526.13
1965 – P.G. & E. #5 3,250.37
2007 – Grade 2 59.80
2012 – Stony 5.73
2013 – Crane 158.94
October 2017 Fire Event
During the night of October 8-9, multiple offshore wind
driven fires ignited across the Counties of Napa and
Sonoma. While no official cause has been determined at the
time of this writing, sparks from electrical lines in strong
winds are considered the likely cause. Sonoma County
experienced the wettest winter on record in 2016-2017
(driving vegetation growth), and one of the ho ttest summer
on record in 2017 (drying out the same vegetation). These
factors combined to create conditions favorable for rapid
fire growth. The City of Santa Rosa to the north experienced
significant devastation and loss of life in the Tubbs Fire due
to the sudden and overwhelming nature of the event.
An offshoot of the Nuns/Adobe fires, centered in and around
Sonoma Valley, headed east over the hills, generally staying
south of Crane Canyon Road during the early hours of
Monday October 9. The City of Rohnert Park mobilized
over the coming days to build emergency fire breaks around
the eastern and northern sides of the City. The G, H, and K
Sections were evacuated for a period of time. Actions by
the City, combined with shifting wind patterns prevented
the fire from directly damaging the City of Rohnert Park.
Figure 3.19: October 2017 Sonoma County Fires
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*After more thorough analysis of the fire event conducted by Sonoma County, Cal OES, FEMA, and the City of Rohnert
Park, additional modifications and additions to this LHMP as pertaining to wildfire hazard mitigation will be included.
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Figure 3.20: October 2017 Sonoma County Fires in the Rohnert Park Vicinity
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Minor or Secondary Hazards
While not identified as primary hazards through the planning process, these hazards are still important and have the potential to
directly or indirectly threaten lives, property, and infrastructure in and around Rohnert Park.
Hazardous Materials
Hazard Description
California law defines a hazardous material as follows:
A substance that, because of physical or chemical properties, quantity, concentration, or other characteristics, may either (1)
cause an increase in mortality or an increase in serious, irreversible, or incapacitating illness; or (2) pose a substantial present or
potential hazard to human health or environment when improperly treated, stored, transported, or disposed of, or otherwise
managed (California Health and Safety Code Section 25141b).
Hazardous materials are dangerous substances that encompass a wide range of substances that include toxic substances, flammable or
explosive materials, corrosive substances such as acids, and radioactive substances. While some hazardous materials are dangerous at
all times, others may only be dangerous under specific conditions such as flammable materials, which can be harmless until exposed
to a spark or a heat source. Hazardous materials that are no longer used and have been disposed of or awaiting disposal.
Emergencies involving hazardous materials are often technological and Man-made Hazards. These types of emergencies also
sometimes occur as a secondary impact of another emergency such as an earthquake or flood.
Hazard Location and Extent
Hazardous material releases can occur from buildings such as factories and processing facilities, as well as from vehicles that transport
chemicals or other hazardous substances. Road vehicles, trains, and (more rarely) aircraft can all suffer accidents that cause a release
of hazardous materials. According to the Rohnert Park Emergency Preparedness Plan 2010, the likelihood of occurrence is every so
often, and the severity of an instance could range of low to high.
Hazard History
According to county reco rds indicated by the Rohnert Park Emergency Management Plan, spill history indicates most problems
occurring in the transportation corridors. Although most of these incidents have been easily handled, the potential still exists for an
extreme threat to life, the environment, and property.
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Hazard Vulnerability and Risk Assessment
In the City of Rohnert Park, commercial businesses that use hazardous materials include, but are not limited to, dry cleaners, film
processors, auto service providers, drycleaners and medical clinics. Residences also generate household hazardous wastes in the form
of paints, thinners, pesticides, fertilizers. Earthquake shaking can release hazardous materials. There is the potential that trucks or train
cars carrying dangerous materials could be tipped over by an earthquake and materials dangerous to health or the environment could
be released. Some of these sources may contain gases or liquids that are potentially harmful to human health. Leaking products present
a serious fire hazard (Rohnert Park Emergency Preparedness Plan 2010).
Hazardous materials also pass through the City in route to other designations via the freeway, rail, and surface street system. The
Department of Transportation (DOT) regulates the transport of hazardous materials on state highways and rail lines using established
criteria for safe handling procedures. Federal safety standards are also included in the California Administrative Code and the
California Health Services Department regulates the haulers of hazardous waste (Rohnert Park Emergency Management plan 2010).
Risk of Future Hazards
An accident with hazardous materials can happen every once in a while, and especially during a natural disaster like an earthquake or
sever e flooding. This makes it a risk probability of three due to its relation to high risk probability hazards. Hazardous waste
generators and users in the City are required to comply with regulations enforced by several federal, state, and county agencies. The
regulations aim toward reducing risk associated with human exposure to hazardous materials and minimizing adverse environmental
effects. Sonoma Fire Department in partnership with the Rohnert Park Department of Public Safety for fire protection services
conduct inspections related to hazardous materials. The Hazardous Materials Compliance Division of the County Environmental
Health Services Department ensures compliance and reporting in accordance with the Sonoma County Hazardous Waste Management
Plan. Highways 101 has a greater potential for a Hazardous Materials release, Petaluma Hill Road and the Rohnert Park Expressway also
has materials traveling through on a daily basis. (RP Emergency Management Plan 2010).
Landslides
Hazard Description
Landslides occur when soils on a hill side become unstable and slide down towards the base of the hill. They can occur very quickly
or may transgress slowly over a period of days, weeks, months, or years. Landslides are capable of damaging or destroying any
structures built on or in the moving so il, and the flow of material can cause further damage to any structure in its path. Landslide risk
depends on the types of earth materials of the hillside and the steepness of the slope.
There are multiple types of landslides and they can be triggered by a number of different events, but the two most common forms are
earthquake-induced landslides and moisture-induced (rain, flooding, irrigation) landslides. During Earthquakes a landslide can happen
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because the ground shaking causes the soil unstable and loose. During the rainy season, moister-induced landslides can occur when
the ground soaks up excess water causing the ground to weaken and become unstable. Water is capable of eroding the base of slops on
hillsides causing risk of landslides.
Hazard Location and extent
According to the Rohnert Park Emergency Management Plan, the likelihood of occurrence in very infrequent, and the severity of the
occurrence is low. Landslides can occur in the event of a major Earthquake at a magnitude of 7 to 7.9. However, areas designated at
risk of landslides are entirely outside and away from the city limits.
The rolling hills, coastal ranges, and steep canyons that characterize Sonoma County’s landscape contribute to a widespread landslide
hazard. Landslides are described as downward movement of a slope and materials under the force of gravity. In addition to gravity,
extended periods of intense rainfall during the winter months is the primary cause of landslides in the County. Landslides can also be
triggered by seismic activity. Landslides are a significant secondary hazard to wild land fire, where periods of heavy rainfall on
denuded slopes cause landslides and mudslides.
The main types of landslide activity that can impact Sonoma County include:
• Slides: Mass movements, where there is a distinct zone of weakness that separates the slide material from more stable
underlying material.
• Falls: Abrupt movements of masses of geologic materials, including rocks and boulders that become detached from steep
slopes or cliffs.
• Debris Flows: Rapid mass movement of a combination of loose soil, rock, organic matter, air, and water that mobilize as a
slurry flowing down slope. These are most often caused by heavy precipitation and intense surface water runoff in steep
gullies.
• Mudflows: Earth flow consisting of material that is wet enough to flow rapidly and contains at least 50 percent sand, silt, and
clay sized particles. Mudflows can travel at speeds of 35 mph or greater.
• Creep: Imperceptibly slow, steady, downward movement of slope-forming soil or rock.
• The occurrence of landslides is determined by both natural and human factors. Natural factors include the cohesive strength
and shrink-well characteristics of the affected minerals, the orientation of joints and planes of weakness between slide material
and bedrock, the steepness of slopes, the degree of saturation of ground materials (highly affected by rainfall), and the density
of vegetation. Human factors include the over steepening and overloading of slopes, the removal of natural vegetation, and the
addition of water to the soil by watering of lawns and septic system drain fields, and onsite ponding of storm runoff.
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Hazard History
Numerous minor landslides have occurred in Sonoma County in areas adjacent to Rohnert Park. However, due to Rohnert Park’s
relatively flat topography, and the relative stability of the hillsides immediately adjacent to the City, any impacts from landslides
outside the city limits are anticipated to be indirect and/or minor.
Hazard Vulnerability and Future
Risk Assessment
The landslide risk in Rohnert
Park is largely outside the city.
All of Rohnert Park, and its
critical facilities are located in
flat areas within the City limit,
and none are considered to be at
risk. Landslides are a risk
probability of two due to this.
Figure 3.21: Landslide Risk
around Rohnert Park
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Figure 3.22 Landside Hazard Probability
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Dam Inundation
Hazard Description
The US Army Corps of Engineers built Warm Springs Dam
across Dry Creek. Completed in 1982, this rolled-earth
embankment dam is 319 feet (97 m) high, 3,000 feet (900 m)
long, and 30 feet (9 m) wide at the top. It contains
30,000,000 cubic yards (23,000,000 m3) of earth. The dam
aids in flood control, and a hydroelectric plant produces
electricity from the water released downstream. A minimum
amount of flow must be maintained in Dry Creek to
allow fish migration.
Hazard Vulnerability, Extent, and Future Risk Assessment
The Warm Springs Dam was assessed in 2006 and, after
considering probability of failure and potential failure consequences, categorized it as being in Dam Safety Action Class (DSAC) IV
based upon the Dam Safety risk. Dams in Class IV are considered to be marginally safe, in that the combination of life or economic
consequences with probability of failure is low. No potential failure modes were identified using existing data.
Although no potential failure modes caused by flooding were identified, the consequences of a dam failure were analyzed. A relatively
low probability of failure along with a moderate sized downstream population, residential and commercial structures including
contents, roads, farm land, bridge damage, and utilities, has led to the dam’s inclusion in the DSAC IV category. The consequences
are judged to be similar for breaches caused by seepage, overtopping, or a seismic even. Portions of the communities of Healdsburg,
Windsor, Santa Rosa, Sebastopol, and Guerneville, as well as some rural population areas in the floodplain immediately downstream
of the dam, would be at risk if the dam failed as they are within the 1 to 24 hour flood wave travel time bracket. Half of the rural
population immediately downstream of the dam is important as -half are within a 15 minute flood wave travel time and all are within a
1 hour flood wave travel time. Based on the 2000 Census of Population and flood inundation maps, up to 84,854 people could be
impacted from a dam failure, with an estimated loss of life of up to 100 people from a maximum flood event. Damage includes
industrial and residential structures and their contents, roadways, infrastructure, agriculture (mainly viticulture), and bridge damage
along the Dry Creek. The estimated damages are up to $13 billion, including $219 million for repairing the dam. Potential inundation
areas are found in the County map in the Appendix. Only minor impacts are expected in the worst case scenario along the western
edge of Rohnert Park. Dam failure has been identified as a risk probability of one due to this very low risk.
Figure 3.23: Warm Springs Dam at Lake Sonoma
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Earthquake Faulting
Hazard Description
Surface fault ruptures can result from large magnitude earthquakes.
Surface rupture occurs when movement on a fault deep within the earth
breaks through to the surface. Structures located within the fault rupture
zone are subjected to excessive ground deformations. Most structures are
not designed to withstand such large deformations and experience major
damage. Pipelines crossing the fault zones can also be damaged by the
stresses. During the 1906 San Francisco earthquake horizontal
displacement along the San Andreas Fault averaged 15 feet in Sonoma
County. The Healdsburg, Rodgers Creek and Maacama faults also show
evidence of surface displacement during the past 11,000 years.
Surface rupture is the most easily avoided seismic hazard. The Alquist-
Priolo Earthquake Fault Zoning Act was passed in 1972 to mitigate the
hazard of surface faulting to structures for human occupancy. Its main
purpose is to prevent the construction of buildings used for human
occupancy on the surface trace of active faults. It requires projects to
conduct a geologic investigation to demonstrate that proposed buildings
will not be constructed across active faults. A structure for human
occupancy cannot be placed over the trace of the fault and must be set
back from the fault (generally 50 feet).
Hazard Types
Earthquake Faults: A fault is a fracture along between blocks of the earth’s crust where either side moves relative to the other.
Strike-slip : Strike -slip faults are vertical or almost vertical rifts where the earth’s plates move mostly horizontally. From the
observer’s perspective, if the opposite block looking across the fault moves to the right, the slip style is called a right lateral fault; if
the block moves left, the shift is called a left lateral fault.
Figure 3.24: Earthquake Hazards in California
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Dip-slip: Dip-slip faults are
slanted fractures where the
blocks mostly shift
vertically. If the earth above
an inclined fault moves
down, the fault is called a
normal fault, but when the
rock above the fault moves
up, the fault is called a
reverse fault. Thrust faults
have a reverse fault with a
dip of 45 ° or less.
Hazard Vulnerability, Extent,
and Risk Assessment
No known faults are located
in Rohnert Park. The
Rodgers Creek/Hayward
Fault Zone is several miles
east of the city limits, and
could potentially sever Crane
Canyon Road –
disconnecting the City’s
direct link to the Bennett
Valley area. While
earthquakes are high risk, the
fault zone is located far
enough away that it is a risk
level of one.
Figure 1.1 Risk Assessment Concept
Figure 3.25: Location of nearest fault zone to Rohnert Park
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Summary of Vulnerabilities
This Table identifies the Critical Facilities that are at
risk from potential hazards. The facilities are classified
into separate categories including Government Center,
Community, Fire, Health, Parks, and Schools. Facilities
with more than a low level risk to specific hazard are
denoted accordingly and shaded in orange. As landslide,
and hazardous material risks are low throughout the
community they are omitted from the table.
Primary Vulnerabilities
• Localized Flooding (based on local
experiences from winter storms)
• Flooding based on FEMA 100 and 500 Year
Flood Event Maps
• Earthquake Shaking
• Earthquake Liquefaction
• Drought
• Wildland-Urban Interface Fire
Secondary Vulnerabilities
• Dam Inundation
• Landslides
• Hazardous Materials
• Earthquake Fault Ruptures
Figure 3.26: Winter storm induced flooding on Commerce Blvd.
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Vulnerability Analysis of Critical Facilities
This analysis was conducted by analyzing the location of these facilities in relation to the relative likelihood and intensity of the
potential hazards that could impact them. The table does not include several potential hazards that affect only a few select areas or
facilities in Rohnert Park (such as dam inundation), nor potential hazards that pose only a low level of vulnerability in Rohnert Park
(such as Hazardous Materials). Similarly, landslides, and earthquake faulting are not included in this table as they do not have the
potentially to directly impact the City of Rohnert Park (though there is the potential of secondary impacts from these hazards).
Table 4.1: Vulnerability Analysis
Facility Address Facility Type
Flood
(Local)
Flood
(FEMA)
Earthquake
(Shaking)
Earthquake
(Liquefaction) Drought
WUI-
Fire
City Properties
City Hall
130 Avram
Avenue
Government
Center High High Medium
Corporation
Yard (Public
Works)
600 Enterprise
Drive Public Works High Medium
Senior Center
6800 Hunter
Drive Community Medium High Medium
Community
Center
5401 Snyder
Lane Community Medium High Medium
Burton Avenue
Recreation
Center
7421 Burton
Avenue Community High Medium
Spreckels
Performing Arts
Center
5409 Snyder
Lane Community Medium High Medium
Callinan
Recreation
Center
5405 Snyder
Lane Community High Medium
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Facility Address Facility Type
Flood
(Local)
Flood
(FEMA)
Earthquake
(Shaking)
Earthquake
(Liquefaction) Drought
WUI-
Fire
Animal Shelter
301 J Rogers
Lane Community High Medium
Pump Facility
201 J Rogers
Lane Public Works Medium High Medium
Public Safety
Facility (Main)
500 City
Center Drive
Government
Center High Medium
Fire Station 2
(North)
5200 Country
Club Drive Fire High Medium
Fire Station 3
(West) (Future)
5870 Labath
Avenue Fire High Medium
Fire Station 4
(South)
1312 Maurice
Avenue Fire High Medium
State Farm
Expressway
Landscaping
State Farm
Expressway Public Works High Medium Medium
Enterprise
Avenue
Landscaping
Enterprise
Avenue Public Works Medium High Medium Medium
Water Tanks
Various
Locations Public Works High High High Medium
Parks
Alicia Park
300 Arlen
Drive Park
Benicia Park
7471 Bernice
Avenue Pool
Benicia Pool
7421 Burton
Avenue Park High Medium
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Facility Address Facility Type
Flood
(Local)
Flood
(FEMA)
Earthquake
(Shaking)
Earthquake
(Liquefaction) Drought
WUI-
Fire
Caterpillar Park
7430 Circle
Drive Park Medium
Colegio Vista
1200
Southwest
Boulevard Park
Dorotea Park
895 Santa
Dorotea Park Park
Eagle Park
1115 Emily
Avenue Park High
Gold Ridge Park
1455 Golf
Course Drive Park High
Golis Park
1450 Golf
Course Drive Park Medium Medium High Medium
Honeybee Park
1170 Golf
Course Drive Park High Medium
Honeybee Pool
1170 Golf
Course Drive Pool High High Medium
Ladybug Park
8517 Liman
Way Park Medium
Magnolia Park
1401
Middlebrook Park
Magnolia Pool
1501
Middlebrook
Way Pool High Medium
Oak Grove Park
(Future) Keiser Avenue Park High High Medium
Rainbow Park
1345 Rosana
Way Park
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Facility Address Facility Type
Flood
(Local)
Flood
(FEMA)
Earthquake
(Shaking)
Earthquake
(Liquefaction) Drought
WUI-
Fire
Sunrise Park
5201 Snyder
Lane Park Medium High
Twin Creeks
Park Kerry Road Park High Medium
Willow Glen
Park (Future)
Bodway
Parkway Park High
Robert's Lake
5010 Robert's
Lake Road Park High Medium
Rohnert Bark
(Dog Park)
5010 Robert's
Lake Road Park
Field Of Friends
(Dog Park)
7471 Bernice
Avenue Park
Creekside
Multi-Use Paths N/A
Multi-Use
Paths Medium Medium High High High
Municipal Golf
Course (North)
100 Golf
Course Drive Park High Medium Medium Medium
Municipal Golf
Course (South)
100 Golf
Course Drive Park Medium Medium
Non-City
Facilities
California
Highway Patrol
6100 Labath
Avenue State High Medium
SMART Station
N/A (Rohnert
Park
Expressway) Transportation High Medium
Sutter Pacific
1400 Medical
Center Drive Medical Medium Very High Medium
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Facility Address Facility Type
Flood
(Local)
Flood
(FEMA)
Earthquake
(Shaking)
Earthquake
(Liquefaction) Drought
WUI-
Fire
Kaiser
Permanente
5900 State
Farm Drive Medical High Medium
Rohnert Park
Health Center
2149, 5900
State Farm
Drive Medical High Medium
Urgent Care
Center
1450 Medical
Center Drive Medium High Medium
Urgent Care
Center
6174 State
Farm Drive High Medium
Satellite Heath
Care Rohnert
Park
6265,
Commerce
Boulevard,
Suite 156 High Medium
Rohnert Park
Cancer Center
301
Professional
Center Drive Medical High Medium
Schools
Marguerite
Hahn
Elementary
825 Hudis
Street School Very High Medium
Evergreen
Elementary
1125 Emily
Avenue School Very High Medium
Technology
Middle School
7165 Burton
Avenue School High Medium
Rancho Cotate
High School
5450 Snyder
Lane School Very High High
Monte Vista
Elementary
1400 Magnolia
Avenue School Very High Medium
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Facility Address Facility Type
Flood
(Local)
Flood
(FEMA)
Earthquake
(Shaking)
Earthquake
(Liquefaction) Drought
WUI-
Fire
Lawrence E.
Jones Middle
School
5154 Snyder
Lane School Medium Very High Medium Medium
Richard Crane
Elementary
1290
Southwest
Boulevard School High Medium
John Reed
Elementary
390 Arlen
Drive School High Medium
Waldo Rohnert
Elementary
550 Bonnie
Avenue School High Medium
Technology
High School
1801 East
Cotati Avenue School Very High High
La Fiesta
Elementary
8511 Liman
Way School High Medium
Sonoma State
University
1801 East
Cotati Avenue University Very High High Medium
Credo High
School
1300 Valley
House Drive School Medium Medium Medium
Mobile
Home/RV
Parks
Rancho Verde
650 Rohnert
Park
Expressway
Mobile Home
Park
Very
High
Very
High High Medium Medium
Rancho Grande
5099 Snyder
Lane
Mobile Home
Park Medium Very High Medium Medium Medium
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Facility Address Facility Type
Flood
(Local)
Flood
(FEMA)
Earthquake
(Shaking)
Earthquake
(Liquefaction) Drought
WUI-
Fire
Rancho Feliz
6607 Redwood
Drive
Mobile Home
Park Medium High Medium Medium
Valley Village
6401 Country
Club Drive
Mobile Home
Park High High Medium
Las Casitas
7545 Bridget
Drive
Mobile Home
Park High Medium
Wine Country
RV Park
7450 Cristobal
Way RV Park High Medium
Table 4.2: Infrastructure Vulnerability and Exposure
Hazard Roads
(miles)
Rail/Transit
(miles)
Total Miles of Infrastructure 130 4
Earthquake Shaking (within highest two shaking categories) 130 4
Liquefaction Susceptibility (within moderate, high, or very high liquefaction susceptibility 130 4
Earthquake-Induced Landslides 0 0
Earthquake Faulting 0 0
Flooding (within 100 year floodplain) 6 0
Flooding (within 500 year floodplain) 5 0
Landslides (within areas of existing landslides) None None
Wildfires (subject to high, very high, or extreme wildfire threat) None None
Wildland-Urban Interface Fire Threat 17 1
Dam Inundation (within inundation zone) <1 0
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Potential Impacts to Critical Facilities from Earthquake
Bed Loss in Hospitals
The City of Rohnert Park has two medical facilities; Kaiser Permanente on State Farm Drive and St. Joseph’s Urgent Care Center on
Medical Center Drive. There are a total of eight major medical facilities within Sonoma County. Public service agencies and volunteer
personnel would be used to assist in the care of the injured.
Several of the acute care hospitals in Sonoma County may be lost due to structural damage. In addition, even the most modern
hospitals can be incapacitated by non-structural damage. Earthquake shaking can damage sensitive equipment, topple storage units,
and dislodge ceilings or light fixtures. Damage to water pipes could flood portions of buildings. Damages can be serious, and it can
cause major areas within hospitals to be nonfunctional during the critical hours immediately following a major quake. This will
decrease the number of beds available and create the need for alternate treatment facilities or field hospitals. Although a percentage of
the remaining beds could be made available by discharg ing or transferring non-emergency patients, it will probably be necessary to
receive an immediate influx of emergency medical aid and/or export some of the seriously injured to out-of-county facilities.
Building Survivability
An earthquake could shake all parts of the City of Rohnert Park and Sonoma County. Every building in the City is exposed to high
risk of damage in earthquakes by virtue of being located in a seismically active part of the country. Some of these structures face an
elevated risk because they are located in high hazard zones, such as near the fault, on liquefiable soils, or on slopes subject to
landslides. Other structures face high risk because their construction quality is inadequate to withstand strong shaking, primarily
because they were built decades ago before modern building codes were enacted. Some structures house critical City and County
functions, such as emergency response activities, and it is important that these structures remain functional after an earthquake.
Communications
System failure, overloads, loss of electrical power and possible failure of some alternate power systems will affect telephone and
cellular systems. Numerous failures can be expected to occur, and the systems will be overloaded beyond capacity. The anticipated
damage could disable up to 80% of the telephone system for one day. In light of this, emergency planners should not expect the use of
telephone or cellular systems for the first few days after the event.
The City of Rohnert Park and Sonoma Co unty as a whole have a wireless communications network used for public safety and
emergency response. The communications network is used by the County and City agencies, public safety officials and emergency
responders. The network is comprised of remote mountain top communication sites, consisting of towers and equipment buildings,
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which provide wireless communications coverage throughout Sonoma County. While the communications system is designed to be
functional even after the loss of one or more antennas, a major earthquake impacting multiple sites could significantly reduce
communications effectiveness.
Electrical Power
Major power plants are expected to sustain some damage due to liquefaction and the intensity of the earthquake. Up to 60% of the
system load may be interrupted immediately following the initial shock. According to representatives of PG&E, electrical power may
not be rerouted, resulting in wide spread outages for an undefined period of time. A great deal of the imported power is expected to be
lost. In areas of greatest shaking, it should be anticipated that some distribution lines, both underground and surface, would be
damaged. Much of the affected area may have service restored in days; areas that suffer extensive damage or have underground
distribution may require a longer time.
Fire Operations
Although total collapse of fire stations is not expected, possible disruption of utilities, twisted doors and loss of power can create
major problems. Numerous fires due to disruption of power and natural gas networks can be expected. Many connections to major
water sources may be damaged and storage facilities would have to be relied on; water pressure and supply could be inadequate to
non-existent. First response from fire personnel is expected to be damage assessment and determining resources needed for response
and recovery needs. Response could be further complicated and delayed by the disruption of transportation routes.
Secondary responses by the fire service will focus on search and rescue of trapped persons. Rescuers should expect loss of power and
water, jammed doors, restricted mobility due to debris, possible loss of communications capability and delays in reaching maximum
effectiveness due to personnel shortages.
Roads, Highways and Bridges
Many roads in the County of Sonoma traverse areas subject to liquefaction and landslides. Roadways that experience liquefaction can
develop very large cracks that prevent their use, and can develop smaller cracks and sinkholes that impede traffic. Landslides triggered
by earthquakes can both block and rip out sections of roads. Numerous roads will be subject to delays and detours. Damage to freeway
systems is expected to be major, despite seismic upgrades. Portions of surface streets in the vicinity of freeways may be blocked due
to collapsed overpasses. Many surface streets in the older central business district will be blocked by debris from buildings, falling
electrical wires and pavement damage. Local bridges that have not been seismically retrofitted may experience a high percentage of
failure. The failures of major roadways in the county could impact safe routes for mutual aid resources responding to the Cit y of
Rohnert Park.
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Sanitation Systems
Many of the wastewater treatment facilities could be disrupted, depending on the severity and intensity of the earthquake and damage
caused by liquefaction. There is a limited amount of storage available in the wastewater treatment plants; if the treatment train cannot
be restored before the storage is exceeded, wastewater will require discharge with emergency chlorination to reduce health hazards.
Overflow of sewage through manholes and from ponds can be expected due to breaks in sewer mains and loss of power. As a result,
there may be danger of excessive collection of explosive gas in sewer mains, and flow of untreated sewage in some street gutters.
Many house sewer connections will break and plug.
Water Supply
Several ruptures are anticipated along the water pipelines in the City and County Areas. A majority of water wells are expected to be
disabled by loss of electricity and the lack of backup power sources. In addition, shear forces could render about a third of the wells
inoperative for an indefinite period. Water availability and distribution for needed life support, to treat the sick and injured and for fire
suppression activities is of major concern to each community.
Social Vulnerability Analysis
A hazard event has the potential to effect members of the community in varying ways, even if the extent and severity of the hazard is
precisely the same. In some cases, an earthquake event may be more impactful and damaging to persons of lower income, as they are
more likely to lack the financial resources to have retrofitted their home to be more resistant and resilient to ground shaking. A
community member’s vulnerability to a hazard situation could also be affected by other factors such as age, disability status,
education, English proficiency, or other factors. Together, these factors reflect a community member’s vulnerability independent of
the hazard or disaster itself. This is known as social vulnerability.
Table 4. 3 Community-Wide Social Vulnerability Metrics
Social Vulnerability Metric Totals
Number of residents 42, 622
Number of households 15,808
Number of households with children 4,363
Median household income $58,317
Percentage of households under the poverty limit 15.2%
Number of elderly households 3,048
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Number of adults without a high school diploma 3,072
Percentage of people with limited English proficiency 9.5%
Percentage of households with a disabled family member 12.5%
MITIGATION AND ADAPTATION STRATEGY
The purpose of hazard mitigation is to reduce potential losses from future disasters. The intent of mitigation planning, therefore, is to
maintain a process that leads to hazard mitigation actions. Mitigation plans identify the natural hazards that impact communities,
identify actions to reduce losses from those hazards, and establish a coordinated process to implement the plan. (44 CFR §201.1(b))
The findings of the vulnerability and risk assessments in the previous chapter were used to develop actions that reduce and/or
eliminate potential losses from relevant hazards.
FEMA Element C: Mitigation Strategy
• C1. Does the plan document each jurisdiction’s existing authorities, policies, programs and resources, and its ability to expand
on and improve these existing policies and programs? 44 CFR 201.6(c)(3)
• C2. Does the Plan address each jurisdiction’s participation in the NFIP and continued compliance with NFIP requirements, as
appropriate? 44 CFR 201.6(c)(3)(ii)
• C3. Does the Plan include goals to reduce/avoid long‐term vulnerabilities to the identified hazards? 44 CFR 201.6(c)(3)(i)
• C4. Does the Plan identify and analyze a comprehensive range of specific mitigation actions and projects for each jurisdiction
being considered to reduce the effects of hazards, with emphasis on new and existing buildings and infrastructure? 44 CFR
201.6(c)(3)(ii) and 44 CFR 201.6(c)(3)(iv)
• C5. Does the Plan contain an action plan that describes how the actions identified will be prioritized (including cost benefit
review), implemented, and administered by each jurisdiction? 44 CFR 201.6(c)(3)(iii) and 44 CFR (c)(3)(iv)
• C6. Does the Plan describe a process by which local governments will integrate the requirements of the mitigation plan into
other planning mechanisms, such as comprehensive or capital improvement plans, when appropriate? 44 CFR 201.6(c)(4)(ii)
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Hazard Mitigation Goals, Priorities, Benefits narrative
The City of Rohnert Park established LHMP mitigation priorities and goals as a component of the planning process in order to guide
the development of a thorough plan. The goals were developed by the planning team and drawn from the previous LHMP and the
City’s General Plan. The mitigation goals and priorities for the LHMP are:
1. Implement the Local Hazard Mitigation Plan to increase Rohnert Park’s level of preparation for potential disasters and to
minimize the impacts associated with natural and man-made hazards.
2. Identify strategies and tools to facilitate community disaster and hazards awareness and education.
3. Provide for the safety of Rohnert Park citizens by maintaining efficient, well-trained, and adequately equipped City
personnel.
4. Encourage a disaster-resistant City and surrounding area by reducing the potential for loss of life, property damage, and
environmental degradation from disasters and hazards.
5. Reduce the vulnerability of public and private facilities and infrastructure to the effects of earthquakes, flooding, and
drought.
6. Promote conditions and strategies that will accelerate the capacity for physical and economic recovery from disasters and
hazards.
Hazard Mitigation Goals
As presented in the previous section, Mitigation Priorities and Goals, the City of Rohnert Park’s hazard mitigation goals outline and
guide the development of wise policy choices that protect community members, critical facilities, infrastructure, property, and the
area’s natural resources from hazards. These goals shape future actions taken by the Cit y and community to reduce risk and minimize
losses from natural disasters. To ensure implementation of the LHMP is completed as planned, the goals serve as checkpoints that
responsible departments can use to check progress of mitigation action items. The City of Rohnert Park will use the hazard mitigation
actions outlined in Hazard Mitigation Goals and Priorities of potential hazards. These actions were identified through analysis of the
City’s 2010 LHMP, existing plan actions and Capital Improvement Program projects, data collection, research, and collaboratio n with
Rohnert Park’s LHMP team. The actions are separated by hazard addressed, although some may address risk associated with multiple
natural hazards.
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2010 Hazard Mitigation Priorities and Actions
During the hazard mitigation planning process, City staff reviewed the mitigation priorities and actions previously prepared for the
City’s 2011 LHMP. Appendix D, provides the previous mitigation actions from the 2011 plan as well as progress notes and status
updates on these actions. As part of this process these actions were reviewed and taken into consideration. Because of the regional
scale of the 2011 update process, mitigation actions were written generally. With that in mind, the City opted to develop new
mitigation actions specific to the update process conducted in 2017. As a result some of the themes and topics addressed in 2011 are
still being addressed in 2017, however the wording of the mitigation actions has changed to better suit the City’s current needs.
Regardless of these wording modifications, the City’s mitigation priorities are still in line with the 2011 hazard mitigation plan. After
mitigation goals were completed, hazards identified and described, and risk assessed, the LHMP Team prepared draft actions, and
revised and prioritized them based on data analysis and local knowledge about the risks and priorities associated with each hazard.
FEMA directs local governments to use the following criteria as part of its evaluation of mitigation actions:
• The frequency and severity of individual hazard types, and the vulnerability of the community to these hazards
• The impacts reduced or avoided by the action
• The amount of benefits provided by the action
• The critical facilities benefited by the action, including the number of facilities and their importance
• The environmental benefits of the action
Hazard Mitigation Prioritization
Throughout 2017, meetings of the LHMP team, draft hazard mitigation actions were revised and prioritized using data analysis of risk
from each hazard as well as local knowledge about the priorities of community members. Through discussion and self-analysis, the
LHMP team discussed the STAPLE/E (Social, Technical, Administrative, Political, Legal, Economic, and Environmental) criteria, as
described in Table 5.1, when considering and prioritizing the most appropriate mitigation alternatives for the city. This methodology,
as endorsed by FEMA, requires that social, technical, administrative, political, legal, economic, and environmental considerations be
taken into account when reviewing potential actions to undertake. This process was used to help ensure that the most equitable and
feasible actions would be undertaken based on the City’s unique capabilities. The LHMP team did not subject the mitigation measures
to a formal STAPLE/E analysis, but discussed how STAPLE/E would be used when applying for grant funding to implement any
mitigation measures, and considered how the mitigation measures might be evaluated under the STAPLE/E criteria. It was intended
that this analysis would be reserved for submittal of grant applications for mitigation actions proposed within this plan.
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Mitigation Goals and Mitigation Actions Development
Figure 5.1 and 5.2: Mitigation Goals and Mitigation Actions Process
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Table 5.1 STAPLE/E Criteria
Issue Criteria
Social • Is the measure socially acceptable to City residents?
• Would the measure treat some individuals unfairly?
• Could the measure reasonably cause potential social disruption?
Technical • Is the measure likely to reduce the risk from a hazard, or will it only reduce the consequences of the risk?
• Will the measure create more problems or exacerbate existing ones?
• Is the measure the most useful course of action to address the risk, given the goals of the City?
Administrative • Does the City have the administrative capabilities to implement the measure?
• Is the City’s staff available to coordinate and lead implementation of the measure?
• Does the City have sufficient technical support, staff, and funding for implementation?
• Dos the City face administrative barriers to implementation?
Political • Is the measure politically acceptable to the City and to other jurisdictions within the City’s borders?
• Do community members support beginning and or/continuing measure implementation?
Legal • Does the City have the authority to i mplement the measure and enforce it as needed?
• Are there potential legal consequences or barriers that could reasonably hinder measure implementation?
• Could the measure expose the City to legal liabilities?
• Could the measure reasonably face legal challenges?
Economic • What are the monetary costs of the measure, and do these costs exceed the monetary benefits?
• What are the start-up, maintenance, and administrative costs associated with the measure?
• Has funding for the measure been secured, or is there a source of funding available?
• How will the measure affect the City’s financial capabilities?
• Will the measure reasonably place any potential burden on the local economy or tax base?
• What are the budgetary and revenue effects of the measure to the City?
Environmental • How will the measure effect the environment?
• Will the measure need environmental regulatory approvals?
• Will the measure reasonably affect any endangered, threatened or otherwise sensitive species?
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Hazard Mitigation Cost – Benefit Review
Local governments are required to consider the costs and benefits of a full range of mitigation activities that can be implemented to
reduce the potential effects of a particular hazard within the specific community. Cost-benefit analysis is generally used in hazard
mitigation to provide guidance on whether the benefits to life and property protected through mitigation efforts have the pot ential
outweigh the costs of the associated mitigation action. The conducting of a cost-benefit review for a particular mitigation activity has
the ability to assist communities in determining whether a project is substantially worth undertaking in order to minimize or even
avoid damages later on.
An LHMP must demonstrate that a process was employed that emphasized a substantial review of the cost -benefits when evaluating
and prioritizing mitigation actions. The cost -benefit review must be comprehensive enough in the way it reviews actions so that it can
sufficiently evaluate the monetary and non-monetary benefits and specific costs that are tied to each action.
Factors to be considered in a cost-benefit analysis:
• How large an area is potentially impacted?
• How many people are expected to benefit from the action?
• How do critical facilities and infrastructure benefit from the action?
• Does such an action make sense for the environment?
The LHMP Team used a simple method to estimate and determine the relative cost of mitigation activities. The table identifies the
relative cost of mitigation actions, which uses three categories: $ - Indicates Low Cost (<$50,000), $$ - Indicates Medium Cost
($50,000-$100,000), and $$$ - Indicates High Cost (>$100,000). During the City’s implementing period, and annual review of the
plan, more specific costs will be determined, and the cost-benefit matrix refined as necessary.
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Mitigation Actions
The Rohnert Park LHMP Team utilized data from the Hazard Profiles and Vulnerability Assessment, Capabilities Assessment, and
progress on past actions to formulate Mitigation Actions for the new LHMP. The Table below identifies the proposed mitigation
actions, who the responsible city department would be, some potential funding sources, the individual action’s overall priority and
goal completion date, which mitigation goal the action fulfills, and the relative cost: $=low, $$=medium, $$$=high.
The following abbreviations are used in the table:
• Dev. Services: Rohnert Park Development Services Department (includes Planning, Engineering, and Building).
• Admin.: Rohnert Park Administration
• Public Safety: Rohnert Park Department of Public Safety (combined police and fire)
• I.T.: Rohnert Park Information Technology
• Public Works: Rohnert Park Department of Public Works
• HMGP: Hazard Mitigation Grant Program
• FMA: Flood Mitigation Grant Program
• PDM: Pre-Disaster Mitigation Grant Program
• FMAG: Fire Management Assistance Grant Program
• CIP: Capital Improvement Program
Table 5.2: Mitigation Actions
Mitigation Action Responsible
Department
Potential
Funding
Sources
Target
Complete
Date
Priority Mitigation
Goal
Relative
Cost
1. Multiple Hazards - Related Actions
1.1 Continue to apply appropriate
development conditions/restrictions for
projects in higher hazards zones to reduce
risks
Dev. Services,
Public Safety
General
Fund,
HMGP,
PDM, Cost
Recovery
Ongoing High 4 $
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Mitigation Action Responsible
Department
Potential
Funding
Sources
Target
Complete
Date
Priority Mitigation
Goal
Relative
Cost
1.2 Continue to analyze and improve
emergency response communication. This
strategy should include building redundant
capacity into public safety alerting, and
answering points as well as replacing or
hardening communication systems. Use the
City website and social media for
community outreach purposes.
Admin.,
Public Safety,
I.T.
General
Fund,
HMGP,
PDM,
FMAG,
Other
Grant
Sources
2019 Low 2, 3, 4 $
1.3 Continue to assess critical facilities that are
vulnerable to damage from natural
disasters, including availability of backup
power and sufficient supplies to maintain
essential functions, and make
recommendations for appropriate
mitigation.
Dev. Services,
Public Safety,
Public Works
General
Fund,
HMPG,
PDM,
Other
Grant
Resources
2018 High 5, 6 $
1.4 Retrofit, replace, or relocate critical
facilities that are shown to be vulnerable to
damage in natural disasters.
Public Works General
Fund,
HMGP,
PDM, Cost
Recovery,
CIP
2040 Moderate 4, 5,6 $$$
1.5 Continue to participate not only in general
mutual-aid agreements, but also in
agreements with adjoining jurisdictions and
special districts for cooperative response to
fires, floods, earthquakes, and other
disasters.
Public Safety General
Fund,
HMGP,
PDM,
Other
Ongoing Low 1, 2 $
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Mitigation Action Responsible
Department
Potential
Funding
Sources
Target
Complete
Date
Priority Mitigation
Goal
Relative
Cost
Grant
Sources
1.6 In accordance with the adaptation
strategies of the Sonoma County Climate
Action Plan (SCCAP) continue to regularly
inform, and solicit feedback from City
organizations on potential climate change
risks, and hazards with all departments as
relevant.
Dev. Services,
Public Safety,
Public Works
General
Fund, Cost
Recovery
Ongoing Moderate 2, 4 $
1.7 In accordance with the adaptation
strategies of the SCCAP, revise Rohnert
Park's General Plan, and other applicable
documents to better integrate, and
prioritize climate change issues, and best
practices during required updates and as
funding opportunities permit.
Dev. Services General
Fund, Cost
Recovery
Ongoing High 2, 4, 6 $$
1.8 In accordance with the adaptation
strategies of the SCCAP, integrate climate
change adaptation into future updates of
the Zoning Code and General Plan, and
other related documents.
Dev. Services General
Fund,
Other
Grant
Sources
Ongoing High 2, 4, 6 $$
1.9 Continue to coordinate with Sonoma
County, and surrounding jurisdictions on
emergency notifications, including alerts of
imminent threats or a need to evacuate.
Public Safety General
Fund,
Other
Grant
Sources,
Ongoing Moderate 1, 2, 3 $
CITY OF ROHNERT PARK - 2018 LOCAL HAZARD MITIGATION PLAN
ROHNERT PARK - LHMP 91
Mitigation Action Responsible
Department
Potential
Funding
Sources
Target
Complete
Date
Priority Mitigation
Goal
Relative
Cost
PDM,
HMPG
1.11 To the extent possible, avoid locating new
critical facilities in areas of elevated hazard
risks. Use extensive mitigation measures to
reduce vulnerability if no suitable
alternative site exists.
Dev. Services General
Fund, Cost
recovery
Ongoing Low 4, 5 $
1.12 Continue to work with regional companies
and service agencies, including energy
providers, telecommunications services,
and transit operators, to maintain basic
services as much as possible during
emergency conditions and to restore
services as quickly as possible following an
emergency event.
Public Safety,
Public Works
General
Fund,
PDM,
HMGP
Ongoing Low 4, 5, 6 $
1.13 Work to improve estimates of potential
casualties and property damage as a result
of different emergency situations.
Dev. Services,
Public Safety
General
Fund,
HMPG,
PDM,
Other
Grant
Resources
2019 Low 1, 4, 6 $$
CITY OF ROHNERT PARK - 2018 LOCAL HAZARD MITIGATION PLAN
ROHNERT PARK - LHMP 92
Mitigation Action Responsible
Department
Potential
Funding
Sources
Target
Complete
Date
Priority Mitigation
Goal
Relative
Cost
1.14 Continue to update the City's emergency
planning documents to ensure consistency
with state and federal law, local conditions,
best practices, and most recent science and
technology.
Dev. Services,
Public Works,
Public Safety
General
Fund,
General
Plan
Maintena
nce Fund
2018 High 1, 2, 4 $
1.15 Continue to improve the reliability of the
water supply for emergency response
purposes through new water main
connections and system improvements.
Dev.
Services,
Public
Works,
Public Safety
General
Fund, Cost
Recovery,
Other
Grant
Sources
Ongoing Moderate 4, 5, 6 $$
1.16 Invest in continued training for City staff in
emergency preparedness and response.
All
Departments
Other
Grant
Sources,
PDM,
HMPG
Ongoing Low 3 $$
1.17 Continue to make strategic investments in
modern equipment for City staff.
All
Departments
General
Fund,
Other
Grant
Sources
Ongoing Moderate 2, 3, 6 $$
1.17 Develop a siren network in Rohnert Park to
alert the public on potential hazards.
Dev.
Services,
Public Works
Public Safety
General
Fund,
Other
Grant
Resources
2030 High 2, 4 $$
CITY OF ROHNERT PARK - 2018 LOCAL HAZARD MITIGATION PLAN
ROHNERT PARK - LHMP 93
Mitigation Action Responsible
Department
Potential
Funding
Sources
Target
Complete
Date
Priority Mitigation
Goal
Relative
Cost
CIP
1.19 Continue to maintain and periodically
update the LHMP.
All
Departments
General
Fund,
PDM,
HMPG
Ongoing High 1, 2 $$
2. Flooding
2.1 Sustain the City's participation in FEMA's
National Flood Insurance program (NFIP).
Dev. Services,
Public Works,
Public Safety
General
Fund,
Other
Grant
Sources
Ongoing High 1, 4, 5, 6 $
2.2 When FEMA creates, updates, and
publishes flood zone mapping of the 100-
year and 500-year floodplains, quickly
integrate new information from the maps
into the City's GIS, and use flood
information in the development review and
public project review process. In areas with
high flood risk, continue to evaluate, and
implement flood hazard mitigation projects
to reduce potential for property damage,
street flooding, and stream erosion.
Dev. Services,
Public Works
General
Fund,
Other
Grant
Sources
Ongoing High 1, 4, 5 $$
2.3 Continue to analyze pump station
conditions, capacity, and upgrades when
appropriate.
Public Works General
Fund,
Developm
ent Fees
Ongoing Low 3, 4, 5, 6 $$
CITY OF ROHNERT PARK - 2018 LOCAL HAZARD MITIGATION PLAN
ROHNERT PARK - LHMP 94
Mitigation Action Responsible
Department
Potential
Funding
Sources
Target
Complete
Date
Priority Mitigation
Goal
Relative
Cost
2.4 Evaluate, monitor, and maintain the City's
storm water drainage system to ensure it
can effectively handle anticipated storm
water volumes to the maximum extent
possible, and make upgrades and repairs as
needed. Coordinate with the Sonoma
County Water Agency to clear debris, and
remove vegetation and sediment in flood
control channels within the City to protect
flow capacity.
Public Works General
Fund,
Other
Grant
Resources
Ongoing Moderate 1, 4, 5 $$
2.5 Continue to pursue grant funding to
complete creek restoration projects that
result in bank stabilization, enhanced
habitat, and flood capacity.
Public Works,
Dev. Services
Other
Grant
Resources
Ongoing Low 4, 5 $$
2.6 Retrofit public areas, including plazas,
sidewalks, and parking lots as feasible, to
use permeable paving and other low-
impact development features that promote
infiltration, and reduce storm water runoff.
Public Works General
Fund,
Other
Grant
Resources
, CIP
2040 Low 4, 5 $$$
2.7 Replace bridge at the crossroads of the Golf
Course Dr. and Hinebaugh Creek.
Public Works,
Dev. Services
General
Fund,
Other
Grant
Resources
, CIP
2025 High 1, 2, 3 $$$
CITY OF ROHNERT PARK - 2018 LOCAL HAZARD MITIGATION PLAN
ROHNERT PARK - LHMP 95
Mitigation Action Responsible
Department
Potential
Funding
Sources
Target
Complete
Date
Priority Mitigation
Goal
Relative
Cost
2.8 Continue to pursue project to mitigate
downstream flooding through the
preservation, and construction of regional
drainage basins.
Public Works,
Dev. Services
General
Fund,
Developm
ent Fees,
Other
Grant
Sources
Ongoing Moderate 5 $$
2.9 Construct a system of upstream storm
water detention facilities on the eastern
edge of the community to reduce flooding
risk as new development occurs.
Public Works CIP,
Developm
ent Fees
High 5 $$$
3. Seismic Hazards (Shaking)
3.1 Consider the development of funding
mechanisms to assist building owners’
affordability of retrofits to unreinforced or
retrofitted structures.
Dev. Services General
Fund,
PDM,
CIP
2020 Low 2, 4, 5 $$
3.2 Require the retrofit of seismically
vulnerable structures consistent with City
Code at the time of major renovations or
redevelopment. This program should
include community education and
outreach.
Dev. Services General
Fund,
CIP
2040 Low 4, 5, 6 $$
3.3 Identify/analyze sewer and water lines that
are determined to be structurally deficient,
and retrofit and replace as per
recommendation.
Public Works General
Fund,
Developm
ent Fees,
2020 Low 5, 6 $$$
CITY OF ROHNERT PARK - 2018 LOCAL HAZARD MITIGATION PLAN
ROHNERT PARK - LHMP 96
Mitigation Action Responsible
Department
Potential
Funding
Sources
Target
Complete
Date
Priority Mitigation
Goal
Relative
Cost
HMPG,
PDM,
Other
Grant
Resources
, CIP
3.4 Conduct seismic evaluations of City-owned
properties that contain critical
facilities/operations to determine the need
for upgrades/retrofitting.
Dev. Services,
Public Works
General
Fund,
PDM,
HMGP,
CIP
2024 Moderate 1, 3, 4, 5 $$$
4. Geologic Hazards (Liquefaction)
4.1 Require comprehensive geotechnical
investigations prior to development
approval, where applicable. Investigations
shall include evaluation of liquefaction
potential, settlement, seismically induced
land-sliding, or weak and expansive soils.
Dev. Services Developm
ent Fees
Ongoing Moderate 1, 4, 5 $
4.2 Restrict development from areas where
people might be adversely affected by
natural or man-made geologic hazards,
including unstable slopes, liquefiable or
expansive soils, and poorly engineered fills,
as determined by a California-registered
geologist or engineer.
Dev. Services General
Fund,
General
Plan
Maintena
nce Fund
Ongoing High 4, 5, 6 $$
CITY OF ROHNERT PARK - 2018 LOCAL HAZARD MITIGATION PLAN
ROHNERT PARK - LHMP 97
Mitigation Action Responsible
Department
Potential
Funding
Sources
Target
Complete
Date
Priority Mitigation
Goal
Relative
Cost
4.3 Pursue implementation of regulatory
requirements related to erosion and
sediment control. As needed, adopt
additional, mandatory, minimum sediment
and erosion control measures for current
properties, and those under construction
that exhibit high erosion potential or have
experience past erosion problems.
Sediment and erosion control measures
shall reduce soil erosion from primary
erosional agents including wind,
construction operations, and storm water
runoff.
Dev. Services PDM,
HMGP,
General
Fund,
Other
Grant
Resources
2019 Low 5 $$
4.4 Identify grant programs, and other funding
opportunities to retrofit soft-stories.
Dev. Services PDM,
General
Fund,
Other
Grant
Resources
, CIP
2024 Low 4, 5 $$
5. Hazardous Materials
5.1 Provide reliable water delivery, and
wastewater collection during, and after
disasters to reduce the risk to public health,
and the environment.
Public Works General
Fund,
Other
Grant
Resources
,
Ongoing High 4, 5, 6 $$$
CITY OF ROHNERT PARK - 2018 LOCAL HAZARD MITIGATION PLAN
ROHNERT PARK - LHMP 98
Mitigation Action Responsible
Department
Potential
Funding
Sources
Target
Complete
Date
Priority Mitigation
Goal
Relative
Cost
Developm
ent Fees
5.2 Generate, and support public awareness,
and participation in household waste
management, control, and recycling.
Public Safety General
Fund,
Other
Grant
Resources
Ongoing Low 1, 2 $
5.3 Continue to improve the capabilities of the
Public Safety Department to respond to
new hazardous material
incidents/emergencies.
Public Safety General
Fund,
Other
Grant
Resources
Ongoing Moderate 1, 2, 3 $$
5.4 Update the HazMat Response Plan. Public Safety General
Fund,
Other
Grant
Resources
2019 Low 2, 4, 6 $$
5.5 Develop strategies to enhance protection
of existing groundwater resources from
hazardous material sites.
Public Safety,
Public Works
General
Fund,
HMPG,
PDM,
Other
Grant
Resources
2018 Moderate 2, 4, 5 $$
CITY OF ROHNERT PARK - 2018 LOCAL HAZARD MITIGATION PLAN
ROHNERT PARK - LHMP 99
Mitigation Action Responsible
Department
Potential
Funding
Sources
Target
Complete
Date
Priority Mitigation
Goal
Relative
Cost
5.6 Continue to improve outreach to
businesses that store, handle, and use
hazardous materials over the state
threshold or generate hazardous waste.
Public Safety,
Public Works
General
Fund,
HMPG,
PDM,
Other
Grant
Resources
Ongoing Low 1, 2, 4 $
6. Drought
6.1 Continue to participate in the Russian River
Watershed Association to provide water
conservation guidance, encourage drought-
tolerant landscaping, and reduce the
consumption of potable water.
Public Works General
Fund
Ongoing Low 1, 2, 4 $
6.2 Continue to wisely use, where available,
water resources from the recycled water
system.
Dev. Services,
Public Works
General
Fund,
Developm
ent Fees
Ongoing High 4, 5 $$
6.3 Develop a plan for expediting the repair,
and functional restoration of water, and
wastewater systems through the
stockpiling of materials, temporary pumps,
surface pipelines, portable hydrants, and
other supplies.
Public Works General
Fund,
HMGP,
PDM,
Water
Enterprise
Funds,
Other
2021 Low 5, 6 $$
CITY OF ROHNERT PARK - 2018 LOCAL HAZARD MITIGATION PLAN
ROHNERT PARK - LHMP 100
Mitigation Action Responsible
Department
Potential
Funding
Sources
Target
Complete
Date
Priority Mitigation
Goal
Relative
Cost
Grant
Sources,
CIP
6.4 Host regular workshops, and classes on
water conservation strategies, including
drought-tolerant landscaping. Available
rebates for water conservation, and water
efficiency actions. Continue workshops,
classes and other education efforts even in
the absence of drought conditions.
Public Works General
Fund,
Other
Grant
Resources
2019 Low 1, 2, 4 $
7. Dam Inundation
7.1 Utilize mapping tools to better understand
potential impacts of dam failure on the
recently annexed Northwest Specific Plan
Area and areas along creeks west of
Highway 101 that drain in to the Laguna de
Santa Rosa.
Public Works,
Development
Services
General
Fund, CID,
Other
Grant
Resources
2019 Moderate 4, 5 $
8. Landslides and Earthquake Faulting
8.1 Prepare a report based on mapping
activities documenting potential secondary
impacts of landslides and earthquake fault
ruptures on transportation infrastructure,
utilities, and communications facilities that
service Rohnert Park.
Public Works,
Development
Services
General
Fund
2019 Low 4, 5 $$
CITY OF ROHNERT PARK - 2018 LOCAL HAZARD MITIGATION PLAN
ROHNERT PARK - LHMP 101
Mitigation Action Responsible
Department
Potential
Funding
Sources
Target
Complete
Date
Priority Mitigation
Goal
Relative
Cost
8.2 Assess the potential impact of fire damage
triggered landslides and debris on property
and streams within the City of Rohnert Park
Public Works,
development
Services
Other
Grant
Resources
2018 High 4, 5 $
9. Wildland-Urban Interface Fire
9.1 Continue to monitor the Wildland-Urban
Interface areas of the City, and develop
maps and materials as a part of plan to
mitigate exposure to current and future fire
risks.
Public Safety,
Dev. Services
FMAG,
Other
Grant
Resources
2018 High 1, 4, 5 $$
9.2 Map properties that were impacted by the
October 2017 fires, either directly, or
through Emergency Operations activities,
and assess needs and methods for future
access and emergency response.
Public Safety,
Public Works,
Dev. Services
FMAG,
Other
Grant
Resources
2018 High 1, 4, 5 $
9.3 Monitor weed growth and have bi-annual
weed abatement inspections.
Public Safety General
Fund
2018 High 1, 2, 4 $
9.4 Educate the public on emergency
preparedness and fire risk. Provide training
to most vulnerable to wildfires.
Public Safety General
Fund,
FMAG
2018 High 1, 4 $
9.5 Place cameras on Taylor Mountain and
Sonoma Mountain to monitor potential
wildfires.
Public Safety,
Public Works
General
Fund,
CIP
2024 High 4 $
CITY OF ROHNERT PARK - 2018 LOCAL HAZARD MITIGATION PLAN
ROHNERT PARK - LHMP 102
Mitigation Action Responsible
Department
Potential
Funding
Sources
Target
Complete
Date
Priority Mitigation
Goal
Relative
Cost
9.6 Develop defensible spaces and fuel breaks
Wherever possible.
Public Safety,
Public Works,
Dev. Services
FMAG,
General
Fund,
CIP
2024 High 1,2,4 $$
9.7 Assess what additional equipment,
resources, or authority may be needed to
mitigate the risk of future fire emergencies,
and to respond effectively in the event one
occurs.
Admin.,
Public Safety,
Public Works,
Dev. Services
FMAG,
General
Fund,
Other
Grant
Resources
2018 High 1, 4, 5 $$
$ Indicates Low Cost (<$50,000)
$$ Indicates Medium Cost ($50,000-$100,000)
$$$ Indicates High Cost (>$100,000)
CITY OF ROHNERT PARK - 2018 LOCAL HAZARD MITIGATION PLAN
ROHNERT PARK - LHMP 103
Current Implementation of Select Mitigation Actions
Stream Maintenance to Reduce Flooding Impacts: In Rohnert Park,
Sonoma County Water Agency (SCWA) performs periodic channel
maintenance activities which may include sediment removal, debris
removal, and vegetation maintenance. Though initially designed and
built as constructed channels to move storm water and other runoff
through and away from developed land, the waterways that traverse the
City are thought of by many as creeks -- assets with value beyond
storm water conveyance. Responding to this changing attitude, SCWA
is moving away from the dredging and clearing activities of the past,
and has developed a Stream Maintenance Program that is its new
channel maintenance regime. Follow this link for more on the Stream
Maintenance Program on SCWA's website.
Rohnert Park’s Low Impact Development Strategy: Low Impact
Development (LID) is defined as a design strategy to maintain or
reproduce the way storm water infiltrates or runs off a site before
development occurs. LID principles control storm water runoff by
using small scale landscape based features that are distributed
throughout the site. Projects designed following LID principles must maintain the undeveloped volume of storm water runoff and
mimic the natural water balance through infiltration, evapo-transpiration, or through capture and reuse of storm water.
LID is intended to minimize the impact of development —our buildings, roads, parking lots, driveways— on our watersheds. LID
correlates the relationship between storm water runoff and the land, including our built environment. LID techniques lessen the
quantity of runoff and improve its quality by "slowing, spreading, or sinking" runoff on the site as much as possible. Slowing down
storm water runoff keeps the water in the channels from rising too high and too fast and devastating communities downstream.
Spreading does the same, helping to dissipate the storm water's power. Sinking means infiltrating water through soil, which cleans the
water and recharges the groundwater table.
The City's MS4 permit requires compliance with the City of Santa Rosa and County of Sonoma's LID Technical Design Manual
(dated August 2011). Adherence to these guidelines requires new development projects to incorporate LID design strategies and
BMPs to reduce pollutants in runoff to the maximum extent practicable. The LID manual was updated and in effect as of 2017.
Figure 5.3: 2017 SCWA Stream Maintenance
CITY OF ROHNERT PARK - 2018 LOCAL HAZARD MITIGATION PLAN
ROHNERT PARK - LHMP 104
Capabilities Assessment
An LHMP is required to conduct a capabilities assessment to
identify local personnel, agencies, and resources that have the
capability and capacity to assist with and support hazard
mitigation activities. The LHMP team identified and defined
known local resources available to the City of Rohnert Park.
Many of these resources were used or consulted in the
development of this LHMP. They are briefly summarized in
the table below.
Rohnert Park’s capabilities are, like any governmental
jurisdiction, constantly undergoing refinement and
improvement. The new Westside Fire Station, which has been
approved and is expected to break ground in 2018 will be a
significant upgrade in the physical resources available to the
City in terms of hazard preparedness and emergency response.
Table 5.3: Available Resources
Resource Type Background and Capacity Further Information
City of Rohnert Park
Building Code Policy
Document
Provides a guidance and framework for the
construction and maintenance of structures
within the City in conformance with the
International Building Code. Specifically
formulated to mitigate seismic and fire hazards.
http://www.rpcity.org
Zoning Code Policy
Document
Primary tool to serve as the implementing
document of the General Plan. It sets specific
land use regulations and includes the zoning map
for the City. The zoning code is supplemented by
Specific Plans, and also includes a Form Based
Code for Sonoma Mountain Village. Can be used
http://cityofrohnertpark.hosted.civiclive.com
Figure 5.4: Approved Westside Public Safety Station
CITY OF ROHNERT PARK - 2018 LOCAL HAZARD MITIGATION PLAN
ROHNERT PARK - LHMP 105
Resource Type Background and Capacity Further Information
to mitigate multiple hazards by determining types
of developments in at risk areas.
General Plan Policy
Document
This is the principal policy document that guides
development and ongoing evolution in Rohnert
Park. The General Plan includes programs and
policies pertaining to land use, housing, and
natural resources. This is the current 8th Edition
of the General Plan that was completed in 2000.
A new General Plan process is expected to start in
early 2018. Hazard data and mitigation activities
described in the LHMP can incorporated in to the
General Plan.
http://www.rpcity.org
Fire Code Policy
Document
The Fire Code of the City of Rohnert Park
provides guidance that complies with the
International Fire Code. The code is recognized
for its ability to mitigate fire hazards.
http://www.rpcity.org
Building Code Policy
Document
Specified how new structures can be built. It
provides guidance for the California Building
Code in addition to any amendments made by
the City. Mitigation actions may involve
amending the Building Code to improve a
building’s safety or structural stability.
http://www.rpcity.org
Zoning Code Policy
Document
Is responsible for the practical implementation of
the General Plan. Specifies the physical makeup
of the City. Mitigation actions may involve
amending the Zoning Code to create a safer
community.
http://www.rpcity.org
Emergency
Management
Plan
Policy
Document
The Emergency Management Plan was prepared
in 2012 and outlines the City’s response and
procedures in the event of natural or man-made
hazards.
http://www.rpcity.org
CITY OF ROHNERT PARK - 2018 LOCAL HAZARD MITIGATION PLAN
ROHNERT PARK - LHMP 106
Resource Type Background and Capacity Further Information
Capital
Improvement
Program (CIP)
Funding
Source
The capital Improvement Program is the City’s
primary method for upgrading and maintaining
critical infrastructure. This program allocates
funding to see these improvements through. The
CIP is a key vehicle for implementing actions from
the LHMP.
http://www.rpcity.org
Administration Personnel
Resource
Rohnert Park’s administrative unit handles
finance, personnel, and overall
administration/management.
http://www.rpcity.org
Public Safety Personnel
Resource
The department, which combines the functions
of police and fire, conducts emergency
preparedness activities for the community.
Mitigation activities related to emergency
preparedness can be implemented by the
department.
http://www.rpcity.org
Public Works Personnel
Resource
The department is responsible for the
construction and maintenance of the City’s
physical infrastructure.
http://www.rpcity.org
Development
Services
Personnel
Resource
The department, which encompasses planning,
engineering, and building, may be responsible for
mitigation activities related to its functions.
Contains the Project Manager.
http://www.rpcity.org
Sonoma County
Emergency
Council
County
Resource
Is responsible for the revision and maintenance
of the Sonoma County Emergency Plan. Is also
responsible for the implementation of mutual aid
agreements throughout the county; to review
and recommend action on all proposed mutual
aid agreements with the United States, the State
of California, other political subdivisions,
corporations, and groups or individuals; and to
http://sonomacounty.ca.gov/Emergency-Council/
CITY OF ROHNERT PARK - 2018 LOCAL HAZARD MITIGATION PLAN
ROHNERT PARK - LHMP 107
Resource Type Background and Capacity Further Information
review and recommend the adoption of such
ordinances, resolutions, rules, and regulations as
may be necessary to implement the County
Emergency Plan or other mutual aid agreement
entered into pursuant to such plan.
Fire Prevention
Division
County
Resource
Is responsible for programs, procedures, and
projects for preventing the outbreak of fires in
the unincorporated areas of the county which
may impact populations, resources, and urban
areas. In addition to code enforcement, Fire
Prevention Division staff is responsible for
hazardous materials incident response, fire
investigations, and Emergency scene
management support at emergencies in
unincorporated areas within the City’s urban
growth boundary.
http://sonomacounty.ca.gov/FES/Fire-Prevention/
Sonoma
County Water
Agency (SCWA)
Agency
Resource
The SCWA is responsible for maintaining over 75
miles of streams throughout Sonoma County and
provides flood protection for facilities in the
county. The SCWA is also the controlling agency
for the water supply system throughout much of
Sonoma County. The water agency can work with
Rohnert Park on drought and flood related
mitigation actions.
http://www.scwa.ca.gov/
Sonoma
County General
Plan
Policy
Document
The Sonoma County General Plan, like Rohnert
Park’s, is the guiding document for the evolution
of the county. Can work with Rohnert Park to
mitigate hazards in the surrounding area.
http://sonomacounty.ca.gov
Sonoma
County Hazard
Mitigation Plan
Policy
Document
The Sonoma County Plan provided general
background information for the development of
http://www.sonoma-county.org/prmd/docs/hazard-
mitigation-update/
CITY OF ROHNERT PARK - 2018 LOCAL HAZARD MITIGATION PLAN
ROHNERT PARK - LHMP 108
Resource Type Background and Capacity Further Information
the Rohnert Park LHMP. Can be used for future
reference on future hazard mitigation plans.
Santa Rosa
Hazard
Mitigation Plan
Policy
Document
The newly approved Santa Rosa Hazard
Mitigation Plan served as a primary resource and
guide for the development of the Rohnert Park
LHMP.
https://srcity.org/540/Local-Hazard-Mitigation-Plan
SCWA Urban
Water
Management
Plan
Agency
Resource
Is a long-range planning document to aid cities in
Sonoma County to help plan for services and
emergencies through 2035. The plan includes
projections for water demands and supplies. Can
aid Rohnert Park in drought related mitigation
actions.
http://www.scwa.ca.gov/
Sonoma
County Climate
Action Plan
Advisory
Document
The Sonoma County CAP, developed by the
Regional Climate Protection Authority was
developed in coordination with all major
jurisdictions in the County. However, prior to
formal adoption by all jurisdictions, the
document was challenged in court and found to
have been inadequate in its full scope to address
GHG emissions. The document is now merely
advisory but includes many useful policies and
recommendations.
https://rcpa.ca.gov/
SCWA Hazard
Mitigation Plan
Agency
Resource
The Sonoma County Water Agency, similar to the
City of Rohnert Park, must develop and publish a
hazard mitigation plan, to be updated every five
years. This plan can aid Rohnert park in future
drought and flood related mitigation actions.
http://www.scwa.ca.gov/
Regional Resources
Association of
Bay Area
Governments
Agency
Resource
Serves as the primary vehicle for Regional
Governance and research particularly in regards
https://www.abag.ca.gov/
CITY OF ROHNERT PARK - 2018 LOCAL HAZARD MITIGATION PLAN
ROHNERT PARK - LHMP 109
Resource Type Background and Capacity Further Information
to planning, land use, hazards, and climate
change.
Metropolitan
Transportation
Commission
Agency
Resource
Coordinates the planning of major transportation
infrastructure improvements throughout the San
Francisco Bay Area including within Sonoma
County. Can help further evacuation routes and
make recommendations for road improvements.
http://mtc.ca.gov/
Pacific Gas and
Electric
Technical
Resource
The Pacific Gas and Electric Company (PG&E)
owns the electricity and natural gas transmission
and distribution system in and around Rohnert
Park. It also provides natural gas service and
some electrical service to the community. PG&E
can work with the City to reduce the vulnerability
of energy infrastructure to natural hazards and to
reduce the likelihood of their infrastructure
triggering or exacerbating a hazard.
https://www.pge.com
State and Federal Resources
California
Department of
Transportation
State
Resource
State agency charged with upkeep and
development of California’s roads and bridges.
Has jurisdiction over Highway 101, which acts as
an evacuation route for Rohnert Park.
http://www.dot.ca.gov/
Office of
Planning and
Research
State
Resource
Constitutes the state planning agency and is
responsible for research and guidance in a
number of different planning areas.
http://www.opr.ca.gov/
California
Office of
Emergency
Services
State
Resource
Cal OES performs its broader mission by
administering numerous programs that support
our stakeholders, protect our communities, and
help create a resilient California. It also provides
notifications for funding opportunities for hazard
mitigation.
http://www.caloes.ca.gov/
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Resource Type Background and Capacity Further Information
State Hazard
Mitigation Plan
Policy
Document
State document that provides guidance at a state
level on mitigation actions to reduce the
vulnerability of the state and its citizens from
hazards. The plan can act as a resource for future
hazard mitigation plans.
http://www.caloes.ca.gov/for.../hazard-mitigation-
planning/state-hazard-mitigation-plan
National
Weather
Service (NWS)
Federal
Resource
Decision support program that improves
forecasts and interpretations and helps to make
more informed decisions.
http://www.weather.gov/
Federal
Emergency
Management
Agency
Federal
Resource
General guidance for hazard mitigation planning
processes and resources. Distributes federal
funding for Hazard Mitigation Grants.
https://www.fema.gov/
Cal-Adapt Technical
Resource
This tool provides estimates of future climate
conditions for locations throughout California,
incorporating the expected impacts of climate
change. Cal-Adapt is a resource for understanding
how climate change may affect natural hazards.
http://cal-adapt.org
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Additional Capabilities – WUI Fire Response
Much of the County’s unincorporated area is designated by the State Board of Forestry as “State Responsibility Areas” (SRA).
California Department of Forestry and Fire Protection (CDFFP) provides “primary” wild land fire protection in these areas. While the
SRA designation implies that only CDFFP provides protection for these areas, local fire districts and Community Services Areas
(CSA) also assist with protecting and responding to fires in them. Technically, a fire district/community services area (CSA 40) that
has SRA lands within it is responsible for providing fire protection to structures, and other improvements. In practice, when a wild
land fire occurs in SRA, a mutual aid system is in place that immediately responds CDFFP fire resources as well as local fire
resources.
Redwood Empire Dispatch Communications Authority (REDCOM) is responsible for notifying local fire resources and CDFFP’s
Sonoma/Lake/Napa Emergency Command Center dispatches CDFFP resources.
Ground fire resources are augmented by CDFFP’s helicopter stationed at Boggs Mountain in Lake County and two air tankers based at
the Sonoma Air Attack Base at the Sonoma County Airport. The Sheriff’s Helicopter Unit (Henry One) is equipped with a 150-gallon
water-dropping bucket that can also assist in the effort when other resources are not available.
Sonoma County’s 40 plus fire agencies have signed a countywide mutual aid agreement to insure that firefighting resources and
personnel will be available to combat a wild land/urban interface fire. If these resources are not enough to meet the threat, fire
resources from throughout California can be summoned under the State’s Master Mutual Aid Agreement administered by the
Governor’s Office of Emergency Services.
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PLAN MAINTENANCE AND ADOPTION PROCESS
FEMA Element D: Plan Review, Evaluation and Implementation
• D1. Was the plan revised to reflect changes in development? 44 CFR 201.6(d)(3)
• D2. Was the plan revised to reflect progress in local mitigation efforts? 44 CFR 201.6(d)(3)
• D3. Was the plan revised to reflect changes in priorities? 44 CFR 201.6(d)(3)
FEMA Element E: Plan Adoption
• E1. Does the Plan include documentation that the plan has been formally adopted by the governing body of the jurisdiction
requesting approval? 44 CFR 201.6(c)(5)
It is of crucial importance that this LHMP is up to date, as this will help ensure that Rohnert Park continues to be protected against
hazards and eligible for state and federal mitigation funding. The Plan’s structure allows the City to easily update individual sections
as information becomes available and as needs arise. This will help ensure that the Plan remains current.
Coordinating Group
Maintaining and updating the LHMP is the primary responsibility of the Rohnert Park LHMP Team. The team consists of the
following departments:
• Human Resource Department
• Public Safety Department
• Public Works Department
• Community Services
• Development Services
A designated member from the planning department will oversee these departments. This designated staff member will be deemed the
project manager. The LHMP project manager will function to coordinate the general maintenance of this plan, conduct the formal
review process, and prepare updates to the plan. The project manager will assign tasks to other team members and present the
plan/related information where needed.
Changes in Priority
From the previous LHMP plan in 2011, there have been multiple changes in priority that have shifted the attention and mitigation
actions that have been developed due to this. The main update to priorities occurred from flooding, wildfires, and the Capital
Improvement Program. Reasons for changes in priority include:
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• Flooding: Over the past five years there has been an increase in localized flooding along Copeland Creek and Hinebaugh
Creek. This has caused a conflict with roadways on both sides of the US 101 and has affected multiple areas within Rohnert
Park. A specialized focus was taken to identify risk to mobile home parks, due to their susceptibility to flooding along the
creeks. Rohnert Park has already started to mitigate these issues by clearing drainage in the area and working with the SCWA
to manage stream flow. A focus on this can be found on page 107 labeled “Current Implementation of Select Mitigation
Actions”.
• Wildfire/WUI: A major update in priorities has occurred in wildfire risk due to the October 2017 wildfires. In the previous
LHMP from 2011, there was only a minor focus on wildfires and it was thought to be a minor threat to Rohnert Park. Due to
the increased risk of wildfires in the area and the 2017 wildfire event, there has been an increased concern over the possibility
of a wildfire in Rohnert Park. There has been an update to threat analysis, mitigation activities, and review of development
plans. The Universit y District located on the east side of Rohnert Park across from Sonoma State was one of the first to have
an increased review for wildfire threat.
• Capital Improvement Program: Related to flooding and wildfires, the capital improvement program has been updated to
protect against future hazards. In example, for wildfire and flooding, having an increased roadway connectivity for evacuations
and getting around hazards.
Incorporation of 2011 Local Hazard Mitigation Plan into Planning Mechanisms
After the creation of 2011 Local Hazard Mitigation Plan, there was an intention to adopt the plan into the Safety Element of the Eighth
Edition of the General Plan and the Capital Improvement Program. While mechanisms such as hard actions have been used and
referenced in these plans from the 2011 LHMP, a specific incorporation into the plan never occurred.
Incorporation into Existing Planning Mechanisms
The City has se veral planning mechanisms that the plan will be incorporated into:
• General P lan (including Safety Element): provides a high-level structure for the City’s hazard mitigation and preparation
activities.
• Specific Plans: Establishes a link between implementing policies of the general plan and the individual development proposals
in a defined area.
• Zoning Ordinance and Building Code: Target vulnerable building types identified in this plan, including soft -story buildings,
through the integration of mitigation actions into development of the building and safety code.
• Capital Improvements Plan: Includes mitigation considerations for vulnerable infrastructure from this plan into the CIP.
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The City has a Safety Element in its General Plan that includes a discussion of fire, earthquake, flooding, and landslide hazards. In
addition, the City enforces the requirements of the California Environmental Quality Act (CEQA), which, since 1988, requires
mitigation for identified natural hazards. The City has used these pre-existing programs as a basis for identifying gaps that may lead to
disaster vulnerabilities in o rder to work on ways to address these risks through mitigation.
A comprehensive update to the City’s General Plan is currently underway. It is anticipated to be adopted in 2020. The General Plan,
Safety Element will be updated incorporate the relevant section of the LHMP. The Capital Improvement Program is updated annually
and will also be updated to incorporate and implement relevant policies.
The Site Plan and Architectural Review (SPAR) will continue to evaluate ways in which mitigation strategies identified in this
planning process can be incorporated into other projects going on within the City to support risk reduction across a broad range of
projects and plans.
Plan Update Process
As required by the Disaster Mitigation Act of 2000, the City of Rohnert Park will update this plan at least once every five years, while
continuously collecting, and analyzing new data by the LHMP Team.
The City of Rohnert Park Planning Department will ensure that monitoring of the LHMP will occur. The plan will be monitored on an
on-going basis. However, any major disasters affecting our City, legal changes, notices from ABAG or Cal OES and other triggers
will be used. When the plan is not being updated, the team should meet at least once annually. This meeting shou ld occur between
department managers at least once a year in April. During this meeting, the team should focus on plan implementation, evaluat ing the
actions identified in the plan being implemented, determining the success rate, and reviewing priorities. These meetings should begin
in 2019 and should be timed with overall department planning. As part of the integration process, the staff members in the meeting
should consider the following:
• Hazard events occurring in the previous year.
• The impacts of these hazards on the community.
• Any mitigation actions that have been implemented in the previous year.
• Mitigation actions that were scheduled to be implemented but have not yet done so.
• The schedule of future mitigation actions, and possible adjustments to the timeline.
• Issues that have not been addressed and possible future new mitigation actions.
• Potential grant or funding opportunities that can be used for mitigation actions.
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• Any other new initiatives that can be used to help the mitigation process.
The LHMP shall provide a record of their finding based on this list. This annual progress report will be distributed and used to
determine if the plan should be updated. The public will continue to be involved whenever the plan is updated and as appropriate
during the monitoring and evaluation process. Prior to adoption of updates, the City will provide the opportunity for the public to
comment on the updates.
Adoption
The Rohnert Park City Council is the primary group responsible for adopting and updating the plan. Re-adoption should occur every
five years. After the plan has been adopted by the City Council, the Rohnert Park Department of Development Services will be
responsible for transmitting the adopted version to Cal OES and FEMA for their records.
Implementation
The effectiveness of the Plan depends on the implementation of the mitigation actions it contains, including how mitigation actions are
incorporated int o existing City plans, policies, and programs. The mitigation actions in the Plan are intended to reduce the loss and
damage from hazard events and to provide a framework for hazard mitigation activities for the City to carry out over the Plan’s
lifetime. The City has prioritized the goals and actions in the Plan, to be implemented through existing mechanisms as the resources to
do so are available. The information in this Plan, including the hazard profiles, the risk and vulnerability analysis, and the mit igation
actions, are based on the best available information, technology, methods, and practices available to the Plan authors as the time this
Plan was prepared.
Continued Public Involvement
Members of the public will continue to be apprised of the act ions of the LHMP team and the LHMP review and update processes
through the City’s website and through distribution of annual progress reports to the media. Copies of this plan will also be distributed
to appropriate offices/facilities (libraries, community centers, etc.). When the LHMP update process begins, the LHMP team will
guide the development of a new public involvement strategy, which will reflect the City’s needs and capabilities at the time. This
strategy will, at a minimum, include directions on the use of the City of Rohnert Park’s website and local media outlets.
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Local Hazard Mitigation Plan Points of Contact
Primary Contact:
Name: Jeff Beiswenger
Title: Planning Manager
Mailing Address: 130 Avram Avenue
Telephone: (707) 588-2253
Email: jbeiswenger@rpcity.org
TECHNICAL APPENDICES AND DOCUMENTS
Appendix A – Acronyms, Abbreviations, and Glossary
Appendix B – Planning Process Documents
Appendix C – Mapping
Appendix D – 2010 ABAG Annex
Appendix E – Supplemental Materials
Appendix F – Plan Review
Appendix G – FEMA Comments