In addition to the levees there are several other flood control infrastructure; specifically the Settling Basin and the Settling Basin Overflow Weir. The Settling Basin is designed to remove excess sediment from Cache Creek before it discharges into the Yolo Bypass and has a handling capacity of 30,000 cfs. The Settling Basin Overflow Weir is the primary control structure for the Settling Basin. The Overflow Weir is currently at elevation 35 (NAVD 88) which results in the Settling Basin being able to handle a flow rate of 30,000 cfs.
The Cache Creek levees primarily protect the City of Woodland and surrounding lands. The areas of Woodland most susceptible to flooding include the industrial areas on the north side of town; these areas experienced flooding when Cache Creek overtopped its banks in 1986.
Putah Creek
Putah Creek has its headwaters on the eastside of Cobb Mountain in Lake County. From those springs, it flow to the south and east eventually into Lake Berryessa. Leaving Lake Berryessa via the Monticello Dam, it continues to flow eastward past Winters and Davis before its confluence with the Yolo Bypass/Toe Drain. Housing in Winters and Davis is particularly susceptible to flooding from Putah Creek.
SMY’s responsibilities begin approximately a third of a mile upstream of Hopkins Road near the University of California Davis Airport and continue downstream on both banks of Putah Creek.
The south bank levee ends approximately a quarter of a mile upstream of Road 106. The north bank levee turns towards the north approximately one mile downstream of Road 106A after which it continues north until it joins the Willow Slough south bank levee.
Monticello Dam restricts the flows on Putah Creek to well below the levee system’s design capacity. Flows from Monticello Dam generally do not exceed 30,000 cfs and in general do not rise to the riverward toe of the levee.
Willow Slough Bypass
Situated between the Cache Creek and Putah Creek Watersheds, the Willow Slough Watershed drains approximately 191 square miles of primarily agricultural lands. Willow Slough Bypass is 373
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formed by an agricultural diversion weir just downstream of the California Northern Railroad.
The South Fork of the Willow Slough runs to the north of Madison, and along with sheet flow contributes to much of the periodic flooding in the town. Buildings throughout Madison, including residences, local businesses, the fire station, school, and community hall are all susceptible to flooding events. Esparto is also vulnerable to flooding as creeks and ditches can back up onto streets due to clogging from vegetation.
SMY’s operations and maintenance responsibilities begin at the weir which diverts flows into the Willow Slough Bypass. The entirety of Willow Slough Bypass is leveed until it discharges into the Yolo Bypass. SMY has jurisdiction over the entire south bank levee, while it’s area of responsibility on the north bank levee only extends as far downstream as the east side of the water pollution control plant. East of the water pollution control plant the Willow Slough Bypass levees are maintained by Reclamation District 2035.
The Willow Slough Bypass has a design capacity of 6,000 cfs. The Davis water pollution control plant releases effluent into the Willow Slough Bypass. Additionally water behind the levees originating from Davis Drain are pumped into the Willow Slough Bypass approximately one mile upstream of County Road 105.
The Willow Slough Bypass levees protect the City of Davis, Davis’ water pollution control plant, Yolo County central landfill and agricultural land.
Yolo Bypass
The 3-mile wide, 40 mile long Yolo Bypass is a man-made leveed channel that extends from the Fremont Weir to a point above the City of Rio Vista, where it returns excess flows to the Sacramento River. The primary purpose of the Yolo Bypass is to provide flood protection to the Sacramento and West Sacramento on the Sacramento River. High water levels on the Sacramento River result in water passing into the Yolo Bypass via the Fremont Weir and Sacramento Weir (when opened). The Yolo Bypass currently experiences an average of 70-80% of flood during most years.
The levees maintained by SMY within Yolo County begin at the upstream end of the Yolo Bypass at the Fremont Weir on both the east and west sides. There is a gap in coverage south of the Wallace Weir on the west side of the Yolo Bypass which is ended by the Cache Creek levees.
The eastern side of the Cache Creek Settling Basin protects against backwater from the Yolo Bypass. Downstream of the Cache Creek Settling Basin, the levees are operated and maintained by Reclamation District 2035 until the south bank of Willow Slough Bypass, where SMY picks up operations and maintenance responsibilities once more. The levees maintained and operated 374
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by SMY continue along the west side of the Yolo Bypass until the north bank of Putah Creek. In addition to the levees which form the Yolo Bypass, there are several other flood control related structures.
Fremont Weir is the upstream limit of the Yolo Bypass. High stages in the Sacramento River result in water flowing over the Fremont Weir and thus into the Yolo Bypass. By having the water leave the Sacramento River and enter the Yolo Bypass, stress on levees downstream on the Sacramento River are reduced and provides a flood risk reduction for the Cities of West Sacramento and Sacramento.
Much like the Fremont Weir, the Sacramento Weir is intended to relieve pressure on the Sacramento River levees by diverting flows from the Sacramento River into the Yolo Bypass.
Unlike the Fremont Weir, the Sacramento Weir is only used during exceptionally high flow events. To allow the Sacramento Weir to pass water, each gate must be manually opened.
The Wallace Weir at the southern end of the Knights Landing Ridge Cut (KLRC) and is intended to prevent fish from entering the KLRC and becoming entrapped in either it or the Colusa Drain.
The Delta Region lies within a floodplain and is faced with a major flooding problem because of inadequate levee construction and maintenance, subsidence, seepage, erosion and seismicity.
The Delta area has been reclaimed by about 1,100 miles of levees along natural and constructed waterways that segregate it into about 120 tracts locally known as islands. The entire region of approximately 700,000 acres is under the influence of the tides and a large part of the land surface is lower than the water on the opposite side of the levees. Many of the islands are 15 to 25 feet below sea level due to the subsidence of the peat land structure. The numerous waterways and channels convey runoff to lower areas of the Delta and eventually to the Pacific Ocean.
Flood fighting has occurred in some parts of the Delta on average once every four years. While most of the Delta levees in Yolo County have stood the test of time, they defy engineering logic.
Their foundations are soft and uncertain, they have a great deal of vegetation including large trees, and they suffer erosion and sloughing due to river velocity and wind wave wash.
Nevertheless, they have served the county very well over many years.
The Delta Islands are subsiding due to lower groundwater, aeration of peat soils, and loss of soil to wind. While some believe, the rate has been curbed over the past years due to conservation protocols, the fact is that some islands are 15’ below sea level. The levees work much harder than they did a hundred years ago.
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Some of the Delta levees essentially serve as a dam repressing hydrostatic pressure every day of the year. This leads some researchers to conclude that the potential for catastrophic failure of the Delta levees due to a seismic event has a concerning probability.
Responsibility for flood protection is distributed among many agencies at various levels of government. At the federal level the three primary agencies are the Army Corps of Engineers, FEMA, and the Bureau of Reclamation. At the state level the primary agencies are the Department of Water Resources and the Central Valley Flood Protection Board. At the local level in Yolo County and the region these agencies include: the County of Yolo and several of its cities; the Yolo County Flood Control & Water Conservation District and various Levee Maintaining Agencies.
Yolo County Flood Control and Water Conservation District Since its creation in 1951, the Yolo County Flood Control & Water Conservation District has served the needs of the local community by managing water resources for farming while stabilizing groundwater for other uses with progressive and pro-active water planning.
Today, the District manages three dams, two hydroelectric plants, two reservoirs, more than 150 miles of canals and laterals and one of the world's longest, inflatable rubber dams. District boundaries encompass 195,000 acres of Yolo County, including the cities of Woodland, Davis and Winters, and the towns of Capay, Esparto, Madison and other small communities within Capay Valley.
Yolo County's primary source of agricultural water comes from 50 miles away in Lake County.
The district obtained the rights to store water in Clear Lake in 1967 when it purchased the privately owned Clear Lake Water Company and the Cache Creek Dam. This gave the district the potential to release up to 150,000 acre-feet of water annually.
However, the District's water right to store water in Clear Lake did not provide enough water to supply farmers during dry years, therefore the district constructed the Indian Valley Dam and Reservoir in 1974-1975. With the completion of the Indian Valley Reservoir in 1975, the district’s water resources became less vulnerable to the dry years which often limit water supplies in Yolo County. The six-mile long, one-mile-wide reservoir with a gross capacity of 300,600-acre feet, provides long-term irrigation storage. The district manages the water that the reservoir holds by releasing it as needed. The dam includes a hydroelectric plant. The cost of the dam and reservoir exceeded $9 million and were funded, in part by two bond issues that were retired on time leaving only a loan, originally scheduled to be retired in 2017. However, due to careful financial management, that loan was retired in 1998 making the project debt free. 376
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The total water supply available to the district water users include surface water from Clear Lake, Indian Valley and Cache Creek, and groundwater recharged by the District's operations.
In all, the district has surface water storage averaging, over a long term, nearly 200,000 acre-feet per year.
The Yolo Water and Power Company finished construction of Cache Creek Dam in 1914. It is situated five miles downstream of Clear Lake and was built to store winter water in Clear Lake that would normally run off into the Sacramento River. Cache Creek is the outlet from Clear Lake, but a rock ledge known as the Grigsby Riffle limits the rate at which water can flow past.
In 1998, the spill gate of the dam was modified to increase safety and minimize damage from floating debris.
The Capay Diversion Dam is located approximately two miles above the town of Capay on Cache Creek. This dam was built by the Yolo Water & Power Company, and it serves as the headworks for the canal system. Here, the water released from Clear Lake and Indian Valley Reservoir is diverted into the West Adams and the Winters canals, which then feed the entire canal system. The Capay Dam underwent a major renovation in 1994 which included the installation of one of the longest inflatable dams in the world. The inflatable dam improves safety and the district’s ability to deliver water.
Located at the base of the western foothills, north of the town of Winters, the Chapman Reservoir is a small, 280-acre-foot dual-purpose reservoir the district maintains for flood control and irrigation purposes.
Levee Maintaining Agencies
The Levee Maintaining Agencies are (further discussion of Levees can be found in the Levee Failure hazard profile section):
1. Reclamation District 150
2. Reclamation District 537
3. Reclamation District 765
4. Reclamation District 785
5. Reclamation District 827
6. Reclamation District 900
7. Reclamation District 999
8. Reclamation District 1600
9. Reclamation District 2035
10. Reclamation District 2068
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11. Reclamation District 108
12. Reclamation District 787
13. Knights Landing Ridge Drainage District
14. Sacramento River Westside Levee District
Predominantly, the Delta remains agriculturally oriented, as evidenced by the fact that more than three-fourths of the entire Delta area is devoted to a wide variety of crops.
The climate in Yolo County is characterized by warm, dry summers and cool, wet winters. The average range of temperatures is between 36 degrees Fahrenheit (°F) in December and 95°F in July. Record extremes range from 11°F to 116°F. Annual rainfall ranges from 16 inches on the valley floor to 30 inches in the mountainous areas at the western edge of the county.
Precipitation is primarily of frontal origin, with over 85 percent occurring from November through March. The quantity of storm runoff is greatly affected by the soil type. Soils in the relatively flat farmlands in the eastern part of Yolo County contain appreciable amounts of clay that cause high runoff rates and flooding in the mildly sloping eastern part of the county.
Since the completion of Monticello Dam on Putah Creek (Lake Berryessa) in Napa County, flooding from Putah Creek and Cache Creek (the two largest streams flowing from west to east across the county) occurs only from Cache Creek overflow in the Capay Valley and south of Cache Creek near the City of Woodland, where flooding occurred in 1958 (FEMA, 1981).
Flooding also occurs north of Cache Creek in the lowlands of the Hungry Hollow watershed, which is a tributary of Cache Creek. The largest flood in the Cache Creek drainage in recent years occurred during February 1958 and was estimated to be a 4-percent annual chance event (State of California, 1969).
In the northern part of the county, flooding occurs along the Colusa Basin Drainage Canal.
Flooding results when precipitation within the basin and runoff from the foothill region to the west combine to far exceed the channel capacity of the canal. The greatest flooding in recent years was in 1958, when flooding along the canal extended 70 miles upstream from Knights Landing (State of California, 1964). Flooding also occurs in the spring and is caused by irrigation practices in the rice fields. Damage can be greater during the spring runoff because it occurs during the growing season.
Flooding frequently occurs in the Cottonwood-Willow Slough watershed south of Cache Creek and in the Dry Slough/Davis watershed north of Putah Creek. The adjacent watersheds are part of the Yolo Creek System. Flows originating in the western part of the watersheds exceed the channel capacity of Dry and Willow Sloughs and their major tributaries, Chickahominy Slough 378
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and Lamb Valley Slough, and cause flooding in the relatively flat agricultural lands in the eastern part of the county. Flooding increases at the eastern side of the county when Sacramento River flows are diverted into Yolo Bypass and gravity flow to the bypass is eliminated. Severe flooding occurred along the Sacramento River and Yolo Bypass in February 1986. Floodwaters pond behind the Yolo Bypass and Willow Slough Bypass levees until flood flows in the bypasses recede.
Yolo County Flood Mapping
As part of the County’s ongoing efforts to identify and manage their flood prone areas, Yolo County relies on a variety of different mapping efforts. A brief description of FEMA and DWR mapping efforts covering the Yolo County Operational Area will be described below.
FEMA Floodplain Mapping
FEMA established standards for floodplain mapping studies as part of the National Flood Insurance Program (NFIP). The NFIP makes flood insurance available to property owners in participating communities adopting FEMA-approved local floodplain studies, maps, and regulations. Floodplain studies that may be approved by FEMA include federally funded studies; studies developed by state, city, and regional public agencies; and technical studies generated by private interests as part of property annexation and land development efforts. Such studies may include entire stream reaches or limited stream sections depending on the nature and scope of a study. The FEMA floodplain are lands subject to the 1% annual change (100-year) flood. FEMA mapping also includes areas subject to the .02% annual change (500-year) flood. The State Senate Bill 5 (SB5) required all communities to map their communities. SB5 requires levee protection in urban areas to a 200-year (or 0.5% annual chance flood). A general overview of floodplain mapping is provided in the following paragraphs.
Communities that are currently subject to flooding include Central Landfill, Clarksburg, East Woodland, Knights Landing, Madison, North Woodland, and Yolo. In addition, portions of the County Airport, Covell, DQ University, Esparto, North David Meadows, Patwin Road, and UC Davis are also located within the floodplain. Historically, nearly all these communities have been considered outside the floodplain. However, recent changes in FEMA mapping, particularly regarding the protection provided by uncertified levees, have designated large portions of the County in the floodplain that were not previously considered to be at risk from flooding (see figures below).
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Figure 3-51: FEMA 100-Year, 500-Year Floodplain
Source: Yolo County, 2030 General Plan
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Figure 3-52: FEMA 200-Year Floodplain
Source: Yolo County, 2030 General Plan
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Awareness Floodplains
The Awareness Floodplain Mapping project is an effort by the California Department of Water Resources to identify all flood hazard areas that are NOT mapped by FEMA. These maps are intended to provide communities with additional information regarding potential flood hazards that are not currently identified. The awareness floodplain maps (Figure 3-53) use approximate assessment procedures, relying on aerial photos and general flood models, to identify potential 100-year flood hazard areas. These areas are shown simply as flood prone areas and do not include specific depths and/or other flood hazard data. Awareness floodplains have been generally identified along minor drainages within the Capay Valley and Putah Creek, as well as Lamb Valley Slough and upper Willow Slough.
Designated Floodways
The Central Valley Flood Protection Board (CVFPB) has the authority to designated floodways in Central Valley and regulate their uses. The CVFPB defines a designated floodway as that portion of the stream channel and adjoining floodplain which is reasonable required to accommodate a design flood event. It can also refer to the floodway between existing levees, as designated by the CVFPB or the State Legislature. The only floodways designated by the CVFPB in Yolo County are the Colusa Basin Drain and that portion of Cache Creek located between the Lake County line and the town of Yolo.
For FEMA, a “regulatory floodway” is defined as that portion of the watercourse and adjacent lands that are needed to discharge the base flood without cumulatively increasing the water surface elevation more than a designated height. FEMA has designated a portion of Cache Creek as a regulatory floodway, between the towns of Capay and Yolo. A portion of Willow Slough is also considered a regulatory floodway, between County Road 27 and the Southern Pacific Railroad, as is a small portion of the Union Pacific Railroad Drain located within the City of Davis.
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Figure 3-53: Yolo County – Awareness Floodplains
Source: DWR
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Figure 3-54: Yolo County – Designated Floodways
Source: DWR
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Flood Insurance Rate Map (FIRM)
The FIRM is designed for flood insurance and floodplain management applications. For flood insurance, the FIRM designates flood insurance rate zones to assign premium rates for flood insurance policies. For floodplain management, the FIRM delineates 1% and 0.2% annual chancer floodplains, floodways, and the locations of selected cross sections used in the hydraulic analysis and local floodplain regulation.
Figure 3-55: Yolo County – FEMA Flood Insurance Rate Maps, 2012 Source: FEMA
Letter of Map Revision (LOMR) and Map Amendment (LOMA)
LOMRs and LOMAs represent separate floodplain studies dealing with individual properties or limited stream segments that update the Flood Insurance Study (FIS) and Flood Insurance Rate map (FIRM) data between periodic FEMA publications of the FIS and FIRM. Figure 3-56 shows the FIRMs being used for the flood analysis for this HMP update. 385
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Figure 3-56: Yolo County – FEMA Flood Zones
Source: Yolo County GIS Map
California Floodplain Mapping
Also to be considered when evaluating the flood risks in Yolo County are various floodplain maps developed by the California DWR for various areas throughout California, and in the Sacramento-San Joaquin Valley cities and counties. The FEMA regulatory maps provide just one perspective on flood risks in Yolo County. SB5 enacted in 2007, authorized Cal-DWR to develop the Best Available Maps (BAM) displaying 1% and 0.5% (200-year) annual chance floodplains for areas located within the Sacramento-San Joaquin (SAC-SJ) Valley watershed.
This effort was completed by DWR in 2008. DWR has expanded the BAM to cover all counties in the State and to include 0.2% annual chance flood zones.
Different than the FEMA FIRMs which have been prepared to support the NFIP and generally reflect only the 1% and 0.2% annual chance flood risks, the BAMs are provided for informational purposes and are intended to reflect current 1%, 0.5% (200-year) as applicable, and 0.2% (500-year) annual chance flood risks using the best available data. The 100-year floodplain limits on the BAM are a composite of multiple 1% annual chance floodplain mapping sources. It is intended to show all currently identified areas at risk for a 100-year flood event, including FEMA’s 1% annual chance flood zones. The BAM are comprised of different 386
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engineering studies performed by FEMA, Corps, and DWR for assessment of potential 1%,
0.5%, and 0.2% annual chance floodplain areas. These studies are used for different planning and/or regulatory applications, and for each flood frequency may used varied analytical and quality control criteria depending on the study type requirements.
The value in the BAMs is that they provide a bigger picture view of potential flood risk to the County than that provided in the FEMA FIRMs. This provides the community and residents with an additional tool for understanding potential flood hazards not currently mapped as a regulated floodplain. Improved awareness of flood risk can reduce exposure of flooding for new structures and promote increased protection for existing development. Informed land use planning will also assist in identifying levee maintenance needs and levels of protection. By including the FEMA 1% annual chance flood zone, it also supports identification of the need and requirement for flood insurance. Figure 3-57 show the BAM for Yolo County Operational Area.
Figure 3-57: Yolo County – Flood Awareness (Best Available) Map Source: California, DWR, Retrieved 5/30/23
Legend explanation: Blue – FEMA 1%, Orange – Local 1% (developed from local agencies), Red – DWR 1% (Awareness floodplains identify the 1% annual chance flood hazard areas using approximate assessment procedures), Pink – USACE 1%, Yellow – USACE 0.5%, Tan- FEMA 0.2%, Gray – Local 0.2% (developed from local agencies), Purple – USACE 0.2%.
PAST OCCURRENCES
Major flooding has occurred in Yolo County in 1937-38, 1940, 1943, 1950, 1955, 1958, 1963, 1967, 1973, 1975, and 1986 (U.S. Department of Agriculture, 1969; State of California, 1964; State of California, 1969; FEMA, 1981; U.S. Department of Agriculture, 1976). Flooding 387
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generally occurs in the relatively flat agricultural lands within the eastern two-thirds of the county. Yolo County received three disaster declarations for flooding in 2017 but these declarations primarily concerned levee damages. There was road damage throughout Yolo County because of stopped up culverts, but flooding was minimal. There were three winter storms that hit Yolo County at the beginning of 2023, causing flooding throughout Yolo County.
Since the 2018 HMP Update, there were a series of major atmospheric river systems between December 2022 and January 2023 that brought substantial rain and high wind causing impacts to Yolo County. There was sloughing levees, building damages, debris cleanup, flooded roads, and other significant impacts. Five Reclamation Districts reported sloughing and erosion in our Yolo County levee systems, causing emergency mitigation techniques using sandbags, plastic, and gravel to prevent levee failures. In addition, the saturated soil from the heavy rain and extreme winds uprooted trees, caused localized damage and debris cleanup. Extreme winds have caused extended power outages throughout the county, impacting water pumping stations at reclamation districts, water treatment plants, and residential and commercial communities that are well dependent. Repeated power outages continued causing disruptions throughout the County.
In March 2023, two similar atmospheric rivers struck northern California, bringing rain, snow, and strong winds. Many people lost power as the storm toppled trees and flooded streets. This storm elevated water levels in the Sacramento River about 32 feet, directing water over the Fremont Weir and into the Yolo Bypass on March 12, 2023. This resulted in closing County Road 22 in Woodland, which runs across the bypass, as the waterflow made its way into the Bypass.
Prior to these storms, Yolo County also experienced atmospheric rivers during the February 2019 storms. Damages caused by these atmospheric rivers included localized flooding in numerous county roads and water sluicing across agriculture fields to another in the Dunnigan, Esparto, Madison, Capay Valley, and Knights Landing areas. There were many accidents reported on city streets as well as on Interstate-5 and Highway 133 which resulted in drivers losing control of their vehicles on rain-slicked roads.
There have been 15 Federal disasters related to flooding in Yolo County. And four state disaster declarations due to flooding, as shown in Table 3-25.
Table 3-25 Yolo County State and Federal Disaster Declarations, 1965-2023* Year Disaster Name Disaster Type Disaster #
State
Declaration #
Federal
Declaration #
1965 Heavy rains & flooding Flood DR-183-CA - 12/24/1964 1983
Coastal storms, floods,
slides & tornadoes Coastal Storm DR-677-CA
- 2/9/1983
1986 Severe storms & Flood DR-758-CA - 2/21/1986
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flooding
1995
Severe winter storms,
flooding landslides, mud
flow Severe Storm DR-1046-CA
- 3/12/1995
1995
Severe winter storms,
flooding, landslides,
mud flows Severe Storm DR-1044-CA
- 1/10/1995
1997
Severe storms, flooding,
mud and landslides Severe Storm DR-1155-CA
- 1/4/1997
1998
Severe winter storms
and flooding Severe Storm DR-1203-CA
- 2/9/1998
2006
Severe storms, flooding,
mudslides, and
landslides Severe Storm DR-1628-CA
- 2/3/2006
2017
Severe winter storms,
flooding, and mudslides Flood DR-4308-CA
- 4/1/2017
2017
Severe winter storms,
flooding, and mudslides Flood DR-4305-CA
- 3/16/2017
2017
Severe winter storms,
flooding, and mudslides Severe Storm DR-4301-CA
3/7/2017 2/14/2017
2019
Severe winter storms,
flooding, landslides, and
mudslides Severe Storm DR-4431-CA
USDA
Contiguous
5/1/2019
-
2019
Severe winter storms,
flooding, landslides, and
mudslides Severe Storm DR-4434-CA
USDA Primary
and Contiguous
5/17/2019
5/17/2019
2023
Severe winter storms,
flooding, landslides, and
mudslides Flood DR-4683-CA
1/4/2023 1/14/2023
2023
Severe winter storms,
flooding, and mudslides Flood EM-3591-CA
1/4/2023 1/19/2023
2023
Severe winter storms,
flooding, and mudslides Flood DR-4699-CA
4/20/2023 4/3/2023
* Data from Table 3-5: Yolo County State and Federal Disaster Declarations, 1965-2023. All years that did not have flooding declarations were removed.
There have been 38 NCDC flood events in Yolo County. No deaths or injuries, $15,327,000 in property damage and $7,800,000 in crop damage due to flood events.
Table 3-26: NCDC’s Flood Events for Yolo County 1950-2/23/2023* Event Type
Number
of
Events Deaths Injuries
Property
Damage
Crop
Damage
Flash Flood 1 0 0 0 0
Flood 37 0 0 $15,327,000 $7,800,000
Totals: 38 0 0 $15,327,000 $7,800,000
*Data from Table 3-9: NCDC’s Flood Events for Yolo County 1950-2/23/2023. All other event types were removed.
LIKELIHOOD OF FUTURE OCCURRENCE
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Likely- Based on previous occurrences of flooding, the probability in Yolo County and its jurisdictions is Likely: Between 10 percent and 100 percent chance of occurrence in next year or has a recurrence interval of 10 years or less.
CLIMATE CHANGE AND FLOODING
Sea Level Rise
Worldwide average sea level appears to have risen about six to eight inches over the past century. Various tidal gauge stations along California’s coast show a similar trend (seven to eight inches). Rising average sea level over the past century has primarily been attributed to warming oceans and related thermal expansion, and the addition of water from melting landbased glaciers and polar ice. Yolo County’s location (more than 50 miles inland from the mouth of the Golden Gate) precludes significant effects from coastal processes, such as wave action.
However, low-lying communities in or near the Delta, such as Clarksburg and Elkhorn (with elevation as low as five feet above sea level), would be more susceptible to flooding as sea level rise continues. According to the U.S. Climate Resilience Toolkit modeling, Yolo County has a very low national risk index rating to flooding due to Climate change (see Figure 3-58).
Figure 3-58: Yolo County Hazard Report: Flooding (page 4) 390
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Source: U.S Climate Resilience Toolkit
VULNERABILITY ASSESSMENT AND IMPACTS
Vulnerability – High
The impact from any flooding event will vary based upon several factors: source of the water; location of water flow; duration of rainfall or source release; topography; presence and/or effectiveness of flood control systems; changes in land use and vegetation; and emergency response preparedness and action. Resulting damage could include the following:
• Injury and death associated with people being trapped in rapidly moving waterways or caught unaware during slow rise conditions.
• Injury and death for individuals attempting to walk or drive across flooded roadways. • Damage to critical infrastructure and essential services through inundation. • Damage to roadways, bridges, and other transportation structures affecting mobility and the ability for people to evacuate flooded areas.
• Release of hazardous materials and starting of fires within damaged or affected structures.
• Damage to buildings and structures in the pathway of rising flood waters. • Public health hazards from contamination of potable water sources; damage to sanitation systems; long term presence of standing water; vector infestation; and introduction of hazardous materials contaminants
• Loss of agricultural products and crops from inundation • Impact to local economy stemming from loss in agricultural, industrial, and commercial productivity.
• Societal impacts involving long-term interruption of normal activity.
The risk of localized flooding to future development can be minimized by accurate recordkeeping of repetitive localized storm activity. Mitigating the root causes of the localized stormwater or choosing not to develop in areas that often are subject to localized flooding will reduce future risks of losses due to localized flooding.
Unincorporated Area
The areas of the unincorporated county most vulnerable to flooding include Esparto, Madison, and West Plainfield where extensive flooding of canals and primary roads can cause damage to structures and homes. Flooding occurs from Willow Slough, Union School Slough, Chickahominy Slough, Dry Slough, and Airport Slough. This flooding can cause accelerated gully erosion of rangelands, increased downstream sedimentation, reduced reservoir storage 391
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capacity, reduced water quality, fisheries degradation, and increased phreatophyte vegetation.
Flooding in the West Plainfield District can cause extensive damage to crops, farm buildings, businesses, residences, septic systems, wells, and vehicles.
The Yolo County Flood Control Water Conservation District (YCFCWCD) canal system acts as drainage conveyance until the canals are too full and overtop the banks in which the canals pose an issue for local landowners. During heavy rainfall and winds, the YCFCWCD’s canal banks can erode and alter the conveyance channel causing Flooding is a periodic and ongoing concern within portions of the Capay Valley. Seasonal rains, coupled with a dependence on limited and relatively unimproved flood control systems to protect areas at risk from inundation places segments of Tribal lands at risk from periodic widespread flooding. The existence of local river systems (i.e. Cache Creek), also contributes to the problem of localized flooding on a periodic basis.
The combination of a narrow stream channel, extensive watershed, steep terrain, and other factors can contribute to extensive flows along the Cache Creek drainage, especially during the winter months when water is released from the Indian Valley Dam to provide space for impounded waters for flood control purposes. Controlled releases of water at the dam may combine with runoff from the watershed within the Capay Valley, resulting in flows exceeding the creek’s normal containment capacity and localized flooding.
In West Sacramento, all the city lies within the natural floodplain of the Sacramento River.
However the impact of floods has been lessened due to levees and the Yolo and Sacramento Bypasses, which divert water flows around the city to the west. Local drainage within the northern part of the city, which has residential and commercial development is controlled by piped storm drain systems and earth-lined drainage channels.
The impact of damage resulting from the flooding hazard, as mentioned, can be extremely variable. Nevertheless, most damage results from rising water that inundates residences and buildings, damage to infrastructure and critical facilities, and loss of ingress and egress by the population in the affected areas and the inability of the jurisdictions emergency response capabilities. Damage from flooding can range from minimal, where the damage to an individual home can be on the order of a few thousand dollars to the complete loss of a building or loss of life from the inability to evacuate from the rising floodwaters.
Critical Infrastructure
In the event of a flooding hazard, there are several wastewater treatment plants located in the City of Davis, City of West Sacramento, City of Woodland, City of Winters, and in the 392
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unincorporated area that would be vulnerable to flooding. As well as many domestic wells throughout Yolo County that have the potential of contamination in a large flood event. There would also be flooding along County Road 89, I-505, CA-128. The two hospitals in Yolo County would be subject to flooding impacts as both are fairly close to the 100-year floodplain. Flooding hazard would cause major damage to these critical infrastructures. The figure below shows a snapshot of some of the critical infrastructures and where they are located to show their flood risk vulnerabilities.
Figure 3-59: Yolo County GIS Map - Flood Risk State
Source: https://yolo.maps.arcgis.com/apps/webappviewer
Access and Functional Needs Individuals
Health hazards and property damage may occur at residential dwellings and businesses in the affected areas if proper flood clean–up actions are not conducted immediately. Contamination due to flooded sewage systems will pose a risk to the health and safety of persons in the affected areas. The continued impedance of floodway maintenance from governmental regulators that often delay, increase the cost of, restrict, and in some cases stop, will continue to place Yolo County residents at risk to flooding from internal drainage as well as from levee failure. In Yolo County there are several adult residential facilities, senior apartments, intermediate care facilities that are located near/or in the 100-year floodplain (as shown below). 393
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Figure 3-60: Yolo County GIS Map - Flood Risk State [filtered by infrastructure] Source: https://yolo.maps.arcgis.com/apps/webappviewer
Climate Change Impacts
Future climate change indicators predict a low risk of future flooding hazards in Yolo County.
However, rising sea levels affecting the San Francisco Bay along the Napa, Solano, and Contra Costa County borders may also worsen flooding in Yolo County and expand the county’s floodplains. It is also possible that sea level rise could reduce the effectiveness of Delta and river levees within the county (reducing the levee freeboard and increasing levee stresses because of the rise in the base level of the adjacent water) which would increase the vulnerability of flooding in Yolo County. However, direct impacts of sea level rise causing secondary flooding hazard impacts in Yolo County are low. Additionally, as mitigation measures continue to get put 394
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in place for flood risk, such as improved levee and drainage systems, raising buildings/structures within floodplains, greater participation in the national flood insurance program etc., impacts of flooding hazards on vulnerable populations, damage to critical infrastructure, and community assets will continue to decrease over time.
3.8.1 LOSS ESTIMATES
Based on FEMA guidance, contents value is estimated at 50 percent of the improved value.
Estimated losses assume that a flood is unlikely to cause total destruction. Losses are related to a variety of factors, including flood depth, flood velocity, building type and construction. Using FEMA’s recommendations, average damage is estimated to be 20 percent of the total building value.
The loss estimates for this assessment should be used for flood risk mitigation, emergency preparedness, and response and recovery only. Uncertainties are inherent in any loss estimation methodology and losses will vary depending on the magnitude of the flood event. Other limitations may include incomplete or inaccurate inventories of the built environment. The assessed values, for example, are well below the actual market values; thus, the actual value of assets at risk may be significantly higher than those included therein. Also, this loss estimation assumes no mitigation and does not account for buildings that may have been elevated above the 1% annual chance event according to local floodplain management regulations. See Table 3-27 for estimated flood losses in Yolo County by jurisdiction:
Table 3-27: Yolo County 100-Year Flood Loss Estimates by Jurisdiction (FY2022-2023) Jurisdiction Parcel
Count
Structure Value Est. Contents
Value
Total Value Loss Estimate*
Davis 17,102 $7,341,897,398 $139,547,629 $7,481,445,027 $165,324,346 West Sacramento 17,529 $6,765,270,948 $367,305,022 $7,132,575,970 $4,980,297,826 Winters 2,688 $719,094,868 $15,548,961 $734,643,829 $9,113,915 Woodland 17,650 $5,941,355,463 $245,779,895 $6,187,135,358 $186,903367 Unincorporated
Yolo County 11,006 $3,403,100,282 $312,651,510 $3,715,751,792 $172,844,568 Source: Yolo County Assessor’s Office
*Loss Estimate: this is the most recent loss estimates obtained at the time of the 2023 HMP Update Parcel Count: this is the number of secured parcels of land. This excludes portions/land areas that are State assessed Structure value: this is improvement value. The figure reported represents the total of the improvement value on the secured and unsecured tax rolls.
Estimated Content value: This is taxable personal property that is located on the property (typically businesses). This reported figure does not report business inventory. This reported figure does not report content in residences.
Total value: the sum of the Structure and Estimated Content value.
3.8.2 PARTICIPATION IN THE NATIONAL FLOOD INSURANCE PROGRAM (NFIP) Despite the construction of massive and relatively effective flood control projects, California remains vulnerable to flooding. A rise in population and development contribute to increased 395
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flood risk throughout the state. In Yolo County, the Director of the Department of Community Services, is responsible for meeting NFIP Requirements. The Department of Community Services delegates responsibilities to staff and other county divisions such as Building Services division, Chief Building Official, to meet NFIP requirements including issuing development permits. Yolo County Housing Element 2021-2029 General Plan has a buildable lands inventory and gets updated accordingly. Yolo County (including all special districts) and the cities of Davis, Winters, West Sacramento and Woodland participate in the National Flood Insurance Program. We also work with Department of Water Resources (DWR) as the coordinating agency for floodplain management in California. DWR provides grants and technical assistance, evaluating community floodplain management programs, reviewing local floodplain ordinances, participating in statewide flood hazard mitigation planning, and facilitating annual statewide workshops.
To address participation and continued compliance with the NFIP, the Yolo County Chief Building Official and Community Services Department, ensures the participating jurisdictions will continue to enforce and adopt floodplain management requirements, regulate new construction in special flood hazard areas, update maps for better identification of floodplains and floodplain management programs and activities, continue to provide public assistance/information on floodplain requirements and impacts. Before issuing a permit to build in a floodplain, the participating jurisdictions must ensure that these criteria are met:
- New buildings and those undergoing substantial improvements must, at a minimum, be elevated to protect against damage by the 1-percent-annual-change flood. - New floodplain development must not aggravate existing flood problems or increase damage to other properties.
- New floodplain development must exercise a reasonable and prudent effort to reduce its adverse impacts on threatened salmonid species.
Structures permitted or built in the county before December 31, 1974 are called “pre-FIRM” structures, and structures built afterwards are called “post-FIRM”. Post-FIRM properties are eligible for reduce flood insurance rates. Such structures are less vulnerable to flooding since they were constructed after regulations and codes were adopted to decrease vulnerability. PreFIRM properties are more vulnerable to flooding because they do not meet code or are located in hazardous areas. The insurance rates are different for the two types of structures. Compliance is monitored by the Floodplain manager/Chief Building Official. Maintaining compliance under the NFIP is an important component of flood risk reduction. All participating jurisdictions that participate in the NFIP have identified initiatives to maintain their compliance and good standing.
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Yolo County has 434 square miles, 256,571 acres and 5,423 individual parcels of floodplain defined by the Federal Emergency Management Agency (FEMA) and the County of Yolo. The regulated floodplain areas are subject to flooding during severe storms. The Yolo County Flood Insurance Rate Maps (FIRM) was first published in 1980 and has been revised over time, mapping Special Flood Hazard Areas (SFHA). Yolo County also has an adopted comprehensive Floodplain Management Program. The jurisdictions participation in the National Flood Insurance Program (NFIP) is shown in the tables below (Table 3-28 and Table 3-29).
Table 3-28: Yolo County Communities Participating in the National Flood Insurance Program CID# Community Name
FHBM
Identified
FIRM
Identified
Current
Effective
Map Date
Reg-Emer
Date Tribal
060424 City of Davis 11/08/77 11/15/79 06/18/10 11/15/79 No 060728 City of West Sacramento - 03/05/90 01/19/95 03/13/90 No 060425 City of Winters 01/23/74 12/01/78 06/18/10 12/01/78 No 060426 City of Woodland 02/01/74 10/16/79 05/16/12 10/16/70 No 060423 Yolo County 10/18/77 12/16/80 05/16/12 12/16/80 No Source: Data obtained from FEMA Community Status Book Report: fema.gov/cis/CA.html Given the flood hazard throughout Yolo County, an emphasis will be placed on continued compliance with the NFIP and participation by Yolo County and the City of West Sacramento in the Community Rating System. The Community Rating System (CRS) is a voluntary program within the NFIP that encourages floodplain management activities that exceed minimum NFIP requirements. Flood insurance premiums are discounted to reflect that reduced flood risk resulting from community actions that meet the three goals of the CRS: 1. Reduce flood losses;
2. Facilitate accurate insurance rating; 3. Promote awareness of flood insurance.
For participating communities, flood insurance premium rates are discounted in increments of five percent according to the community’s classification. Yolo County currently exceeds floodplain management program requirements due to participation in the CRS. Yolo County is currently holds a Class 8 rating. Other cities are encouraged to participate in the CRS. Detailed below is a description of the County’s flood management program to ensure continued compliance with the NFIP. Yolo County currently does not have any NFIP compliance violations and was reaccredited in 2023. Yolo County will be undergoing cycle verification in 2024 and trying to improve CRS classification. Also to be considered are the numerous flood mitigation actions contained in this plan that support the ongoing efforts by the county and the cities to minimize the risk and vulnerability of the community to the flood hazard and to enhance their overall floodplain management programs.
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Yolo County has participated in the NFIP since December 16, 1980. Since then, the County has administered floodplain management regulations that meet the minimum requirements of the NFIP. Under that arrangement, residents and businesses paid the same flood insurance premium rates as most other communities in the country. In compliance with the NFIP, Yolo County adopted a Floodplain Management Ordinance (Title 8 Land Development & Zoning, Chapter 3 Flood Damage Prevention). Yolo County has participated in CRS since 2012. The activities credited by the CRS provide direct benefits to Yolo County and its residents, including:
• Enhanced public safety
• A reduction in damage to property and public infrastructure • Avoidance of economic disruption and losses
• Reduction of human suffering
• Protection of the environment
One objective of the NFIP is to reduce the long-term exposure of buildings to flood damage. To achieve this objective, the NFIP requires that existing buildings be brought into compliance if improvements, including additions and repairs, are determined to be Substantial Improvement. If the cost of proposed improvements equals or exceeds 50 percent of the market value of the building before the improvements are started, the building must be brought into compliance with the requirements for new construction. The building code and existing building code have the same definition for Substantial Improvement and the same requirements. Communities can further reduce flood losses over the long term by adopting a requirement that all improvements and repairs be tracked over time and counted toward the Substantial Improvement determination.
Adopting “cumulative Substantial Improvement” means that buildings would be brought into compliance sooner than if the community administers the basic Substantial Improvement requirement, which applies to each separate application for improvements and repairs. Generally, periods of 10 or 15 years, or the life of the structure, are selected by communities committed to long-term resiliency. Yolo County will use a system for recording and accessing records as necessary to administer a cumulative Substantial Improvement provision. Each time an owner applies for a permit to make improvements or repairs, the records for that building must be checked. Yolo County Floodplain administrator will use the Cumulative Substantial improvement, Model Ordinance Section 103-5, Substantial improvement and substantial damage determinations guide. Yolo County Floodplain administrator also follows the procedures outlined in FEMA’s Substantial Improvement/Substantial Damage desk reference guide.
In the event buildings are damaged in flood hazard areas, the Yolo County Community Works Department will direct their team to determine if the building is considered “substantially damaged” based on the current floodplain management regulations and the flood provisions of the International Codes. The surveyors will use the FEMA Substantial Damage Estimator tool to 398
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determine if damage meets the criteria for Substantial damage when the damage is a structure located in a mapped 100-year floodplain. They will also use this tool to determine if a substantially damaged structure in a mapped 100-year floodplain requires additional repairs to meet Substantial improvement criteria. Improvements may include rehabilitation, remodeling, and lateral or vertical additions.
Contained in the table below is the NFIP policy and claims statistics for Yolo County as of June 2023. The NFIP claims statistics are historical back to 1982/1983 when NFIP started collecting this data.
Table 3-29: Yolo County NFIP Claims Statistics, June 2023 Community Current Policies Total Coverage
Total Written Premium + Federal
Policy Fee
Davis 376 $127,641,000 $239,065
West Sacramento 1,419 $495,658,000 $599,557
Winters 31 $9,150,000 $23,352
Woodland 331 $112,265,000 $244,564
Unknown* 825 $246,320,000 $599,557
Yolo County +
Unincorporated Area 769 $223,837,000 $592,141
Totals 3,751 $1,214,871,000 $2,607,503
City of Davis
In compliance with the NFIP, the City of Davis adopted Article 8.05 FLOOD PREVENTION of the City of Davis Municipal Code. An emphasis in future planning and mitigation actions will be placed on continued compliance with the NFIP.
City of West Sacramento
The City of West Sacramento has been in the NFIP since the City incorporated in 1987, and prior to incorporation was in the NFIP as part of Yolo County. The city began participation in the CRS in 2010, receiving a Class 8 rating in 2011. The city maintains a Class 6 rating today. An emphasis in future planning and mitigation actions will be placed on continued compliance with the NFIP as well as the CRS.
City of Winters
The City of Winters participates in the NFIP. The intent of the program is to reduce future flood losses through local floodplain management and to provide protection for property owners against potential losses through flood insurance. As part of the agreement for making flood insurance available in the community, the NFIP required the City of Winters to adopt a floodplain management ordinance containing certain minimum requirements intended to reduce future flood losses.
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On March 1, 1994, the City Council of the City of Winters adopted Ordinance 94-04, which included floodplain management regulations. Specifically, the purpose of the ordinance was to promote the public health, safety, and general welfare, and to minimize public and private losses to flood conditions in specific areas of the City.
On September 28, 2009, Winters city staff met with a representative from FEMA for a “Community Assistance Visit.” The purpose of the meeting was to provide City staff with the most current information on the NFIP, give staff an opportunity to discuss concerns regarding floodplain management, and assess the City’s enforcement of the local floodplain management ordinance that was adopted to meet the requirements of the NFIP.
FEMA visit resulted in the determination that it was necessary to amend the City’s Flood Damage Protection chapter of the municipal code to reflect changes to the NFIP and to clarify some of the requirements. To bring the city into compliance with the NFIP the City Council of the City of Winters adopted Ordinance 2010-03 on March 31, 2010 amending Chapter 15.64 of the Winters Municipal Code regarding flood damage protection.
City of Woodland
The City of Woodland continues to enforce the compliance with the NFIP through their Flood Plain Management Ordinance. However, as in much of California, FEMA is working with local governments to refine and remap the floodplains. These changes to flood mapping and zoning in Woodland may result in additional properties needing to be insured and evaluated in future plans.
3.8.3 REPETITIVE LOSS AND SEVERE REPETITIVE LOSS PROPERTIES A repetitive loss (RL) property is a FEMA designation, defined as an insured property (or formerly insured property) that has made two or more claims of more than $1,000 in any rolling 10-year period since 1978. Claims must be at least 10 days apart but within 10 years of each other. The term “rolling 10-year period” means that a claim of $1,000 can be made in 1991 and another claim for $2,500 in 2000, as long as both serve as qualifying claims happen within 10 years of each other. An RL property may be classified as a Severe Repetitive Loss (SRL) property under certain conditions. A Severe Repetitive Loss property has had four or more claims of at least $5,000, or at least two claims that cumulatively exceed the buildings reported value.
Table 3-30 shows the Repetitive Loss (RL) and Severe Repetitive Loss (SRL) Properties in Yolo County including the cities as of 2023. There are a total of 34 properties and of these properties countywide, all are residential.
Yolo County RL and SRL Property Information*
Jurisdiction Number of RLP’s RLP Total Payouts Number of SRL’s SRL Total Payouts 400
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Yolo County** 34 $1,432,329.80 0 $0
City of Davis 3 $80,350.20 0 $0
City of West Sac 1 $3,758.64 0 $0
City of Winters 0 $0 0 $0
City of Woodland 0 $0 2 $219,546.40
*most current information as of March 2023
** includes unincorporated Areas
Table 3-30: Repetitive and Severe Repetitive Loss Properties in Yolo County Source: Yolo County Community Services Office
A property does not have to be currently carrying a flood insurance policy to be considered a RL or SRL property. Often homes in communities do not carry flood insurance but are still on the community’s repetitive loss list. The “repetitive loss” designation follows a property from owner to owner, from insurance policy to no insurance policy, and even after the property has been mitigated. Having an insurance policy and making claims that fall into that repetitive loss criteria will put a property on the RL list. Even after the policy on a property has lapsed or been terminated, the property will remain on Yolo County’s RL list.
FUTURE DEVELOPMENT TRENDS & POPULATION PATTERNS
As a result of rapid population growth and escalating housing costs in the past ten years, there has been increasing pressure in the Sacramento Valley to build homes and other structures in natural floodplains. There has been new development in the floodplains since the 2018 HMP Update. The figure 3-48 below shows where planned development is in relation to the 100-year floodplain. Future growth subject to potential flooding includes both the Elkhorn and Knights Landing specific plans. The Covell and Madison specific plans are partially located within the floodplain. The Dunnigan specific plan is largely located outside the 100-year floodplain. As a result, new development located within the floodplain must either elevate improvements and structures or provide a means of community-wide flood protection acceptable to FEMA, such as certified levees, bypasses, or similar measures.
The potential for flooding may increase as storm water is channelized due to land development.
Such changes can create localized flooding problems in and outside of natural floodplains by altering or confining natural drainage channels. Floodplain modeling and master planning should be based on the ultimate built-out land use to assure that all new development remains safe from future hydrologic conditions. While local floodplain management, stormwater management, and water quality regulations and policies address these changes on a site-by-site basis, their cumulative effects can result in floodplain impacts regardless. There has been limited growth within the floodplains of unincorporated Yolo County, due to policies that have restricted growth in general within the unincorporated areas, which has decreased the vulnerability of flooding in the unincorporated areas.
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However, additional population growth in or around the cities could contribute to increased flooding in the county as well as negative environmental implications that can lead to increased risk of flooding and expose people and property to flooding risks. Urban development also increases the amount of impervious surface and therefore increases surface water runoff and accelerates the timing of peak runoff flows. This results in increased erosion, sedimentation, and water quality problems in surface runoff, as well as increased risk of flooding. Awareness floodplains do not result in restrictions on building or development. However, if requested by the local jurisdiction, FEMA can incorporate them into National Flood Insurance Program maps where they would become regulatory. FEMA also requires local cities and counties to regulate development within floodways to prevent any increases in upstream flood elevations.
Overall, as future development incorporates floodplain management regulation, there is continual Countywide support on mitigation including updating flood maps, and increased emphasis on NFIP and CRS incorporation into mitigation planning, this would decrease overall vulnerability to flooding in Yolo County.
LOWER YOLO BYPASS EXPANSION: The 2017 CVFPB identified the potential connection of the Sacramento Deep Water Ship Channel to the Yolo Bypass to expand the capacity of the bypass to convey flood flows. This would include breaching the east levee of the Yolo Bypass along the Deep-Water Ship Channel and constructing a closure gate within the channel to ensure flood flows do not backup and inundate the City of West Sacramento through the Port of West Sacramento during flood events. Although there has not been detailed planning conducted yet, this project would decrease vulnerability to flooding.
In 2021, the County Board approved an expansion to the Teichert-Shifler Mining reclamation site. The current project site is approximately three miles west of the City of Woodland, in unincorporated Yolo County. It is generally bound by County Road 94B to the west, Cache Creek to the north, and CR22 to the south. It is currently proposed that, at the conclusion of the mining activity, the mined land will be reclaimed to agriculture and a mix of habitat uses, including lake, grassland, riparian woodland, and native landscape. Creating more open space and restoring land would decrease flooding vulnerabilities to this area.
To mitigate storm water flooding impacts, one proposed development project is focused on drainage infrastructure improvements. The proposed project would incorporate roadside ditch improvements along 2nd Street between the Post Office and Railroad Street to improve storm water drainage capacity; a buried closed conduit under Railroad Street between 2nd Street and 4th Street (approximately 2.25-foot-wide by 1-foot-deep); an open channel along the east side of Railroad Street between 4th Street and 7th Street (approximately 3-foot-deep, 2:1 side 402
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slopes); removal of the existing concrete arch culvert; and degrade of the abandoned railroad embankment using a 50-foot-wide open cut channel.
Figure 3-61: Existing Development within the 100-Year Floodplain Source: Yolo County 2030 General Plan
3.9 LAND SUBSIDENCE
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Land subsidence is a gradual settling or sudden sinking of the Earth's surface caused by subsurface movement of earth materials. The principal causes include aquifer-system compaction, drainage of organic soils through groundwater pumping, underground mining, hydro-compaction, natural compaction, sinkholes, and thawing permafrost. More than 80 percent of the identified subsidence in the United States is a consequence of underground water exploitation. The increasing development of land and water resources threatens to exacerbate existing land-subsidence problems and initiate new ones.
Aquifer Compaction
Aquifer compaction due to groundwater pumping affects both man-made infrastructures and natural systems. This is caused when large amounts of water are pumped, the subsoil compacts, thus reducing in soil and number of open pores spaces in the soil the previously held water, resulting in the permanent reduction in the total storage capacity of the aquifer system.
The compaction of susceptible aquifer systems caused by excessive groundwater pumping is the single largest cause of subsidence in California, and the 5,200 square miles affected by subsidence in the San Joaquin Valley since the latter half of the 20th century has been identified as the single largest human alteration of the Earth’s surface topography. The second largest cause of subsidence in California is the oxidation (decomposition) of organic soils (USGS, 2017c).
Additionally, as the topography of the land changes by varying amounts in different places, low areas, such as wetlands, change size and shape, migrate to lower elevations, or even disappear.
Rivers may change course or erosion/deposition patterns to reach a new equilibrium.
LOCATION AND EXTENT
Since the 1950s, the primary cause of land subsidence in Yolo County has been groundwater pumping, which has resulted in as much as 4 feet of elevation change in some parts of the County. See Figure 3-62 for the area of recorded historical and current land subsidence caused by groundwater pumping in Yolo County as of 2017.
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Figure 3-62: Land Subsidence in Yolo County due to Groundwater Pumping Source: USGS
See Figures 3-63 and 3-64 for a historical sampling of the total land subsidence in Yolo County over the time periods December 2006 – May 2010 and May - November 2014 respectively.
Yolo County was in a declared drought during both time periods. 405
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Figure 3-63: Land Subsidence in Yolo County December 2006 – May 2010 Source: NASA
Figure 3-64: Land Subsidence in Yolo County May – November 2014 Source: USGS
In Yolo County, the East Yolo sub-basin area has been affected most dramatically, with communities near Zamora, Knights Landing and Woodland having experienced damage and loss of structural integrity to highways, levees, wells and irrigation canals. Wells have experienced well housing collapses. The Yolo sub-basin is bounded on the east by the Sacramento River, on the west by the Coast Range, on the north by Cache Creek, and on the south by Putah Creek.
Some soils in Yolo County expand and contract depending on the level of moisture that they contact, impacting their suitability for safe development. These soils vary in distribution and degree of expansiveness. Yolo County soils are characterized by low, medium, high and very high expansiveness. Soils with “Low” expansiveness have the potential to change up to 3 percent in volume between the wet and dry state of the soil. Soils with “High” and “Very High” expansiveness require structural accommodations to mitigate 4 percent to 9.5 percent changes in 406
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soil volume. Contraction volumes greater than 4 percent directly impact soil suitability for roads, bridges, structures and other types of development. Figure 3-65 identifies expansive soils in Yolo County.
Figure 3-65: Expansive Soils in Yolo County
Source: USDA
The extent of land subsidence could range up to a several inches anywhere in Yolo County, but predominantly across the Yolo sub-basin where groundwater pumping has most significantly 407
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occurred. Due its low area of historic and projected occurrence, landslide is rated as Limited with between 10-25 percent of the operational area affected.
PAST OCCURRENCES
There has been no Federal disaster related to land subsidence in Yolo County. No state disaster declarations due to land subsidence, and there are no NCDC records for land subsidence in Yolo County.
Data from the California Department of Water Resources 2019 Sacramento Valley Subsidence report, showed that land in the Arbuckle area in Colusa County/Yolo County border has sunk
2.14 feet compared with baseline measures in the same location in 2008. The report concluded that areas of Yolo County experienced the most widespread subsidence, in terms of geographic area affected by subsidence, with 31 survey sites measuring a land surface decline between 0.3 and 1.1 feet.
LIKELIHOOD OF FUTURE OCCURRENCE
Likely - The probability of a land subsidence occurring in Yolo County is Likely: Between 10 percent and 100 percent chance of occurrence in next year or has a recurrence interval of 10 years or less. The probability can greatly increase during a drought due to the higher pumping of ground water.
CLIMATE CHANGE AND LAND SUBSIDENCE
Climate change has the greatest impact on land subsidence through extended periods of severe drought, in which there is more likely greater groundwater pumping and human induced subsidence. In areas where climate change results in less annual precipitation and reduced surface-water supply, communities will pump more groundwater. In areas dependent on well water such as areas between Zamora and Knights Landing in Northern Yolo County, and in Central Yolo between Zamora and Davis, there has been increased demand for groundwater supply due to not only drought conditions but also increased irrigation needs due to agricultural practices and population growth/expansion. Also, an increasing population in California will increase demands on groundwater supply. During periods of drought, water levels may be drawn too low which would increase the risk of land subsidence.
VULNERABILITY ASSESSMENT AND IMPACTS
Vulnerability – Low
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groundwater pumping is most prevalent, typically away from creeks and rivers. Sinkholes are not likely to form in the County, however, due to the composition of underlying bedrock that forms the California aquifer system. Cropland is primarily susceptible to land subsidence, where the ground can sink several inches as a heavy pumping of groundwater occurs to replace the missing surface water supply. Between 1925 and 1977, in the Zamora and Knights Landing areas of Yolo, the land sank by 4-6 feet.
Based on the Department of Water Resources (DWR) California Groundwater Update 2020, DWR provided an interactive map with information about land subsidence in California from 2009-2018. The data in the map displayed land elevation changes over varying periods as recorded by a collection of continuous global positioning system stations and is presented for groundwater basins within Yolo County. Vertical displacement estimates are derived from Interferometric Synthetic Aperture Radar (InSAR) data to detect changes in land surface elevation and report in land subsidence. Figure 3-66 and Figure 3-67 show the vertical ground surface displacement in Yolo County from 2016-2022, based on water year.
Figure 3-66: Vertical Ground Displacement in Yolo, 2016-2022 Source: DWR California Groundwater Update 2020
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Figure 3-67: Annual Vertical Displacement Rate, Area in Square Miles Source: DWR California Groundwater Update 2020
FUTURE TRENDS IN DEVELOPMENT & POPULATION PATTERNS
The County’s General Plan addresses land subsidence in relation to groundwater pumping. More information on how to minimize groundwater pumping and related measures are in the Drought hazard profile section. Yolo County is committed to linking its General Plan to this hazard mitigation plan update. This will create an opportunity for wise land use decisions as future growth can impact land subsidence prone areas.
Population growth may affect the impacts of land subsidence in relation to groundwater pumping and drought conditions. If population growth affects agricultural land use, where the area is more vulnerable to land subsidence, then it will increase the vulnerability to land subsidence. This is difficult to determine given that population growth is predicted to occur more in the Cities of Yolo County rather than the unincorporated or rural areas.
3.10 LEVEE FAILURE
A levee is a raised area that runs along the bank of a stream or canal. Levees reinforce banks and help prevent flooding by containing higher flow events to the mainstream channel. By confining the flow to a narrower stream channel, levees can also increase the speed of the water. Levees can be natural or manmade.
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Levee failure flooding can occur as the result of partial or complete collapse or under seepage of an impoundment, and often results from prolonged rainfall and flooding. The primary danger associated with dam or levee failure is the high velocity flooding of those properties downstream of the breach. A levee failure can range from a small, uncontrolled release to a catastrophic failure. Vulnerability to levee failures is generally confined to the areas subject to inundation downstream of the facility. Secondary losses would include loss of the multi-use functions of the facility and associated revenues that accompany those functions.
Approximately 150 years ago, the levees of the Sacramento-San Joaquin Delta were raised to prevent flooding on what remains some of the most fertile farmland in the nation. While the peat soils were excellent for agriculture, they were not the best choice to create strong foundations for levee barriers meant to contain a constant flow of river water. Nevertheless, it was these native soils that were primarily used to create the levee system.
Levee failure flooding would vary in the County depending on which structure fails and the nature and extent of the failure and associated flooding. This flooding presents a threat to life and property, including buildings, their contents, and their use. Large flood events can affect lifeline utilities (e.g., water, sewerage, and power), transportation, jobs, tourism, the environment, agricultural industry, and the local and regional economies.
Lands within the Levee Flood Protection Zones may be subject to flooding due to various factors, including the failure or overtopping of project or non-project levees, flows that exceed the design capacity of project or non-project levees, and flows from water sources not specifically protected against by project levees. Project levees are part of the Federal Flood Control Project and are built to higher standards that comply with U.S. Army Corps of Engineers guidelines. Lands not mapped within a Levee Flood Protection Zone are not invulnerable to flood risk, and some may also experience flooding from these or other related events.
Characteristics of Primary Waterways
The Sacramento River runs along the east side of the Colusa Basin and Knights Landing Basin in a single meandering channel. In general, the ground elevation descends from the Sacramento River southwestward toward the Colusa Basin Drain and the Yolo Bypass in the west.
Floodwaters from a breach along the Sacramento River levees will, therefore, flow generally southwest or southeast toward the Knights Landing Ridge Cut and the Yolo Bypass rather than directly parallel along the river. One relief structure, the Fremont Weir connects the Sacramento River with the Yolo Bypass. The Fremont Weir is intended to remove water from the Sacramento River to lower water elevations downstream. On the north side of the Town of Knights Landing, the Knights Landing Outfall Gates and channel allows water to pass between 411
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the Sacramento River and the Colusa Drain. These gates protect the lower Colusa Drainage Basin from backwater of the Sacramento River and assist with agricultural irrigation operations during the dry season. High flows from the American River at its confluence with Sacramento River in Sacramento can cause the Sacramento River to flow backwards.
The Colusa Drain runs along the western side of the Knights Landing Ridge Drainage District Levee and receives water flows from streams and creeks originating in the Coast Range along with local drainage from the north. Flood waters in the Colusa Drain are contained by levees on its east side maintained from north to south by Maintenance Area 12, Reclamation District 108, and Reclamation District 787. At the south end of the Drain, flood waters pool at the Knights Landing Ridge and flow through the Knights Landing Ridge Cut into the Yolo Bypass. The Knights Landing Outfall Structure and channel connects the Colusa Drain with the Sacramento River at this point to allow controlled water flow between those two waterways.
The Yolo Bypass runs along the western side of the Elkhorn basin and the boundaries of all districts except for the section of RD537 north of the Sacramento Weir. The Yolo Bypass receives water from the Colusa Drain, the Sacramento and Feather Rivers, the Sutter Bypass, and streams and creeks along its west side. At the northern end of the Bypass and the junction of the primary waterways mentioned, the Fremont Weir controls the entry of water into the Bypass.
The Sacramento Bypass runs along the south end of the Elkhorn Basin District along the southern boundary of RD785 and RD537. The Sacramento Weir relieves flow from the Sacramento River and American River into the Yolo Bypass. Sacramento Bypass levees are maintained by the Department of Water Resources as State Maintained Area 8. The 1,920 ft. long weir consists of 48 gates that divert Sacramento River (and American River) floodwaters west down the mile-long Sacramento Bypass and discharges them into the Yolo Bypass.
Reclamation District No. 150 – Merritt Island maintains levees surrounding Merritt Island, protecting 4,740 acres of mostly agricultural land (vineyards and orchards) and approximately 238 residents. The district is located within Yolo County and is bounded by Elk Slough and on the east, the Sacramento River on the west, and Sutter Slough on the South (see Figure 3-68).
Elk Slough has a water control structure and earthen levee across the mouth of the slough on the Sacramento River. The water control structure is operated by RD999 during periods of high flows to prevent flow from the slough on the upstream end. The structure also limits flows based on the lower water end elevations and flows from Sutter Slough. 412
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Figure 3-68: Reclamation District 150
Source: KSN Engineers
District levees are vulnerable to wave wash and erosion on the east levee along the Sacramento River. Additional areas of levee vulnerability include:
• At the Courtland Road (Elk Slough to Road 143) there are seepage issues which were fixed 15 years ago and the toe was rebuilt; however, there are multiple boils and the under seepage issues continue.
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• Along the water side of the levee from Elk Slough to Clarksburg there is a vertical drop, likely due to erosion, down to the water. During high water events this is an area where rock has to be added. The worst seepage area is a 2-mile stretch from Road 143 toward Road 142.
• Seepage along the north end of the Sacramento River. There is erosion along the waterside as well.
• The levee along Sutter Slough is built on top of pure sand and there are under seepage issues.
Agricultural land, including vineyards and orchards, would be susceptible to a levee failure in RD and economic losses would be prevalent.
Reclamation District (RD) 307 provides water drainage and flood control services within its gross service area of 6,000 acres. The District and its sphere of influence are located within Yolo County on the west bank of the Sacramento River approximately 5 miles south of the City of West Sacramento (see Figure 3-69). The District’s topography is relatively flat and is confined by the following surface water features and engineered channels: the Sacramento River, the Babel Slough, and Winchester Lake. The Sacramento River has a design capacity of 100,000 cfs along RD307 levees on that waterway.
The District is in the “flood plain” but no portion of the District is within a floodway. The District maintains 6.59 miles of levees that run adjacent to the Sacramento River. Small nonproject levees run along Winchester Lake on the south side of the District and along Babel Slough on the west side. The entire District is within the legal Sacramento-San Joaquin Delta District and within the scope of the Sacramento River Flood Control Project, as approved by the US Army Corps of Engineers (USACE), Department of Water Resources (DWR) and the Central Valley Flood Protection Board (CVFPB).
In addition to its levees, District-maintained infrastructure includes a main District pump station and approximately 136,900 feet of drainage canals, ditches, and laterals. The District pump system discharges internal drainage into waterways and moves irrigation water from waterways into the District irrigation system. The District is in a rural setting with a nominal growth rate.
The current population is approximately 73 permanent residents. Most of the land in the District is in agricultural use, primarily grapes, vegetables, and grain production that would be vulnerable to a levee failure.
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Figure 3-69: Reclamation District 307
Source: KSN Engineers
Reclamation District (RD) 999 provides water drainage, flood control, and irrigation services within its gross service area of 22,000 acres. The District and its sphere of influence are located within Yolo and Solano Counties, beginning approximately 5 miles south of the City of West Sacramento (see Figure 3-70). The District’s topography is relatively flat and is confined by the 415
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following surface water features and engineered channels: the Sacramento River, the Yolo Bypass/Deep Water Ship Channel, Minor Slough, Sutter Slough, and Elk Slough. The Sacramento River has a design capacity of 100,000 cfs along RD999 levees on that waterway.
The Deep Water Ship Channel contains backwater from the Yolo Bypass and Sacramento River at Cache Slough and has no current, but is susceptible to tidal flows.
The District is in the “flood plain” but no portion of the District is within a floodway. The District maintains 33 miles of levees. District levees run adjacent to the Sacramento River along approximately 1.22 miles, adjacent to the Deep Water Ship Channel along approximately 15.43 miles, adjacent to Minor Slough along approximately 2.32 miles, adjacent to Sutter Slough along approximately 3.74 miles, and adjacent to Elk Slough along approximately 9.66 miles. The entire District is within the legal Sacramento-San Joaquin Delta District and within the scope of the Sacramento River Flood Control Project, as approved by the Army Corps of Engineers (USACE), Department of Water Resources (DWR) and the Central Valley Flood Protection Board (CVFPB).
In addition to its levees, District-maintained infrastructure includes 13 drainage pumping facilities, approximately 260 miles of drainage canals, ditches, and laterals. The District pump system discharges internal drainage into waterways and moves irrigation water from waterways into the District irrigation system. The District is in a rural setting with a nominal growth rate, and there are numerous vulnerabilities to the area from the threat of levee failure. The current population is approximately 1,500 permanent residents primarily in the Town of Clarksburg.
There are also several large winery events that take place in Clarksburg and may attribute to an increase in persons at certain times of the year. A levee threat could require a large-scale evacuation, particularly when a large event is going on. Most of the land in the District is in agricultural use and is susceptible to flooding from a potential levee failure; these areas consist primarily of grapes, vegetables, and grain production. Numerous ag-related businesses operate in the District and several commercial businesses, including the Old Sugar Mill, operate in and around Clarksburg and could be threatened from inundation caused by a levee failure. The Clarksburg area has not flooded since the original levee system was completed. Downtown Clarksburg is at a higher elevation than the rest of the district. However, only about 1/3 of the Clarksburg District population lives in town, 2/3 live outside in surrounding areas.
Specific areas of levee vulnerability include:
• If the levee on the north side of Prospect Island fails it will pass water onto weaker, smaller levees, starting a chain reaction that could cause flooding of the entire District. • On the Miner’s Slough project levee, the waterside berms are gone. 416
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• On Ryer Island, at the bridge crossing, the USACE raised the RD 999 levee to increase the freeboard, but they were not able to complete coordination with Caltrans so there is a 3 foot drop in the RD 999 levee which is 150 feet wide. • There is erosion along approximately one mile of Unit 3 of Sutter Slough. Additionally, the top of the levee is covered in elderberry bushes making the mitigation cost for addressing the erosion far too expensive.
• The levee at Elk Slough failed the USACE inspection due to inadequate cross section geometry.
• There are erosion and under seepage problems in the levee at center of Clarksburg (end of Netherlands Ave/Road 154). The USACE had a project designed to address this.
However, it has not been constructed.
• There is subsidence approximately 10-15 feet from the toe of the levee at Miner’s Slough Corner.
• There are multiple encroachment problems that include approximately 130 separate pipes through the levees.
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Figure 3-70: Reclamation District 999
Source: KSN Engineers
Reclamation District 900 is an independent special district that maintains the majority of the levees that surround West Sacramento. The District overlies approximately two-thirds of the City and has an estimated population of 40,000 people that would be vulnerable to a levee failure.
This area includes several city fire stations and schools as well as the city police station and the 418
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Port of West Sacramento. RD 900 is bound by the Southern Pacific Railroad embankment on the north, the Sacramento River on the east, Shangri-La Slough on the south, and the Deep Water Ship Channel (DWSC) on the west (see Figure 3-71). The DWSC also bisects RD 900 into two district areas.
Figure 3-71: Reclamation District 900
Source: KSN Engineers
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Reclamation District 2035 – Conaway Tract comprises 12.1 miles of levee. The District is responsible for the levee maintenance and drainage services for approximately 20,500 acres of privately owned agricultural land. The Tract is located adjacent to the Yolo Bypass on the east and receives some inflow from the Cache Creek Settling Basin (CCSB) on the north (see Figure 3-72).
Figure 3-72: RD 2035
Source: KSN Engineers
The district works in partnership with the City of Woodland to address flood issues that could impact the southwestern periphery of the City of Woodland, where industrial centers and shopping areas are most susceptible. A breach on the northern segments of the Tract (north of County Road 25) may encroach on the southeast end of the City of Woodland but is not expected to have severe impacts west of County Road 102. Floodwaters will generally flow southeast and may begin to expand and backup against the southern Bypass levees near the junction with County Road 29. While a breach of the West Bypass Levee would not directly threaten the City 420
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of Davis, the City of Davis Wastewater Treatment Plant is particularly vulnerable. The plant is located less than a mile from the levee and is currently not protected by a berm, as the City of Woodland Wastewater Treatment Plant is. Inundation of the City of Davis Wastewater Treatment Plant would result in the loss of wastewater services for the City of Davis for several weeks.
Reclamation District No. 2068 (District) – Yolano was formed in April 1924 to provide retail water supply, flood protection, and drainage to agricultural producers within the district boundary. This now includes the district maintenance responsibilities of their portion of the SRFCP levees in, and adjacent to, the Yolo Bypass.
The district is located in the northwest Delta near the City of Dixon. The district is located in both Solano County (over 11,000 acres), and Yolo County (just under 2,000 acres); 1,280 acres of which lies within the Yolo Bypass (see Figure 3-73). The levee is 8.8 miles long, of which
5.5 miles is along the west bank of the Yolo Bypass, and 3.23 miles is on the back levee. The entire levee system is part of the Sacramento River Flood Control Project, Unit 109, west levee of Yolo Bypass and the east levee of Cache Slough, lying north of the same project levees under the jurisdiction of Reclamation District 2098.
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Figure 3-73: Reclamation District 2068
Source: KSN Engineers
Land use is primarily agricultural, which presents the most significant vulnerability to a levee threat. Pastureland use dominates for livestock; alfalfa, grain, and miscellaneous row crops are also grown. The district plans no major land use changes, although there are statewide planning efforts that, if carried out, could affect land use change, and aspects of the District operation and maintenance of the levee and drainage system.
Reclamation Districts (RD); RD1600, RD827, RD785, and RD537 maintain The Elkhorn Basin, which encompasses approximately 16,549 acres protected by an interdependent levee system (see Figures 3-74-3-77). The Elkhorn Basin RDs are facing many of the same infrastructure, funding, O&M, institutional, emergency response, environmental, agricultural sustainability, and climate change problems as the rest of the region. Levees were constructed in the early 1900s and they do not meet current design standards. Additionally, all levees along the Sacramento River within this basin have elderberry bushes which restrict inspection and maintenance. The protected area is primarily agricultural farmland with a limited number of residences, other 422
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structures, and transportation systems. The primary vulnerabilities would be the loss of cropland. County Road 22, which serves as major transportation corridor between West Sacramento and Woodland, traverses the lower half of this area along the Sacramento River Levee and is particularly susceptible to a failure of that levee. There are several spots along the Sacramento River Levee in these districts that have experienced damage during previous storms and are susceptible to future events.
Transportation systems in the Elkhorn Basin include Interstate 5 which crosses the basin from east to west. The Elkhorn Basin is bounded by three distinct waterways: the Yolo Bypass on the west, the Sacramento River on the east, and the Sacramento Bypass on the South.
Figure 3-74: Reclamation District 1600
Source: KSN Engineers
Specific areas of levee vulnerability for RD 1600 include:
• Along the Sacramento River west levee, 8 miles north of Road 117 and Old River Road, there are three large, deep scour holes approximately 6ft off the waterside toe. • Along the landward side of the Sacramento River levee, 1000 ft north of the Fremont Weir and running for 1.6 miles, the levee side slope is approximately 1:1. This area is 423
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part of the Mid Valley project and RD 1600 has been paying DWR $5,000 per year ($150,000 over 30 years) to repair this levee and bring the side slope to 3:1, but there have been no repairs yet.
• On the Yolo Bypass levee starting 2 miles south of the Fremont Weir and running for 2.3 miles, the levee crown road needs an additional 5-6 inches of base and gravel added to ensure the ability to safely drive the road during patrols in wet weather and high-water events as this road surface gets extremely muddy and deeply rutted. Also, on the landward side of this levee, there have been slope stability issues during each of the previous high-water events. And this levee’s side slope is extremely steep and needs soil to be added to give a 3:1 slope. A half-mile stretch of this levee is eight tenths of a foot under the 1957 profile.
• On the Yolo Bypass levee starting 3-4 miles south of the Fremont Weir, there is erosion on the bypass side from wave wash. The erosion extends down the entire side slope into the Tule Canal. The canal is approximately 80 ft wide and there is no road at the levee toe. With no road it is difficult to access these erosion sites to repair them and maintain them.
Figure 3-75: Reclamation District 827
Source: KSN Engineers
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Approximately 2 miles of the Yolo Bypass levee in RD 785 were never completed when constructed. The levee slope on the bypass side was never rip-rapped as originally designed and the levee needs rock placed onto the crown to allow for winter patrol access and emergency access during flood warning times.
Figure 3-76: Reclamation District 785
Source: KSN Engineers
RD537 is composed of two disparate sections separated by the Sacramento Bypass: the northern portion of RD537 is rural, while the southern portion is developed industrialized land. Areas of levee vulnerability include:
• The crown of the levee on the north side of the Sacramento weir is collapsing due to both under seepage and stability problems.
• The levee along Old River Road around Monument Bend has no berm on the river side. • At Monument Bend, RD 537 constructed an oxbow levee (an interior levee) in 1965 to protect against failure of the Sacramento River levee. During a high-water event RD 537 maintains this oxbow levee which puts the responsibility on DWR and Yolo County to 425
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maintain the river levee and the Old River Road. This will create problems for emergency evacuation.
Figure 3-77: Reclamation District 537
Source: KSN Engineers
Reclamation District (RD) 108 is located along the western edge of the Sacramento River and delivers water to nearly 48,000 acres of farmland within southern Colusa County and northern Yolo County. RD 108 receives water from the Sacramento River under riparian water rights, licenses for appropriation of surface water, and a Settlement Contract with the US Bureau of Reclamation. The first irrigated crops were grains, mostly barley but today include rice, wheat, corn, safflower, tomatoes, beans, vine seeds, cotton, walnuts and fruit. 426
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The district was formed in 1870 under the Reclamation District Law of 1868 for the purpose of forming a district to build levees and “reclaim” land subject to periodic overflow from neighboring rivers and water bodies. At this time the Government was promoting reclamation to develop swamp lands for the improvement and cultivation of the thousands of acres in California. On October 4, 1870, the landowners submitted a petition to the Colusa and Yolo County Boards of Supervisors authorizing the formation of a new Reclamation District and assigned it number 108.
RD 108 is surrounded on three sides by levees, that include the west-side levees from Colusa to Knights Landing along the Sacramento River, a Back Levee along the District’s western boundary to prevent flooding from the Colusa Basin, and then along the slough in the South that at one time took drainage water from the Colusa Basin back to the Sacramento River (see Figure 3-78). The district works in coordination with the Sacramento River West Side Levee District and the Knights Landing Ridge Drainage District to provide maintenance to over 90 miles of levees. All of the levees were originally built by the local landowners using whatever materials available and whatever criteria they chose but have since become part of the federally sponsored Sacramento River Flood Control Project. The levees protect the rural communities in Yolo and Colusa Counties. These levees are integral to the system-wide performance of the Sacramento River Flood Control Project and provide indirect protection to the cities of Sacramento and West Sacramento. Since formation of the levee districts, Sacramento River West Side Levee District, Knights Landing Ridge Drainage District have shared management, personnel and equipment with RD 108. The flood control districts reimburse RD 108 for management and work performed.
Sacramento River West Side Levee District (SRWSLD) - The levees south of Colusa were initially maintained by Reclamation District 108, but the costs for levee construction and maintenance were high and borne by few landowners whereas the benefits of flood protection extended beyond RD 108 boundaries. In 1915 the legislature created the SRWSLD to more accurately reflect the lands benefited. All of the levees were originally built by landowners and have become part of the federally authorized Sacramento River Flood Control Project. The levee system protects the City of Colusa, town of Grimes while also protecting approximately 194,000 acres of farmland.
Knights Landing Ridge Drainage District (KLRDD) - In 1913 the legislature created the KLRDD. The KLRDD is protected by an interdependent levee system, is approximately 4000 acres, and is managed by RD 108 staff. This interdependent system is an integral part of the Sacramento River Flood Control Project and provides protection to the Town of Knights Landing, which is the community most vulnerable to a levee threat along the Sacramento River 427
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in this area. The Knights Landing Levee System is bounded by three major waterways: the Sacramento River on the east, the Yolo Bypass on the southeast, and the Colusa Drain on the west (see Figure 3-78). The basin protected by this levee system is primarily agricultural with one rural community, the Town of Knights Landing. The protected area is within Yolo County.
The KLRDD also contains a portion of County Service Area (CSA) #6, a roughly six mile stretch of levee along the Sacramento River that extends from Knights Landing to the Fremont Weir and is maintained by Yolo County. There are numerous erosion sites located along the levee.
Reclamation District (RD) 787 is located along the western edge of the Sacramento River and services 15.8 square miles of land with 4.4 miles of levee. The District provides levee maintenance, drainage, and irrigation.
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Figure 3-78: RD 108, Sacramento River West Side Levee District, Knight Landing Ridge Drainage District, and RD787
Source: KSN Engineers
Reclamation District (RD) 765 provides water drainage and flood control services within its gross service area of 1,400 acres (see Figure 3-79). The District and its sphere of influence are located within Yolo County on the west bank of the Sacramento River approximately 4 miles south of the City of West Sacramento. The District’s topography is relatively flat and is confined by the following surface water features and engineered channels: the Sacramento River and Babel Slough. The Sacramento River has a design capacity of 100,000 cfs along RD 765 levees on that waterway.
The District is in the “flood plain” but no portion of the District is within a floodway. The District maintains 1.7 miles of levees. District levees run adjacent to the Sacramento River. The entire District is within the legal Sacramento-San Joaquin Delta District and within the scope of the Sacramento River Flood Control Project, as approved by the US Army Corps of Engineers (USACE), Department of Water Resources (DWR) and the Central Valley Flood Protection Board (CVFPB).
The District pump system discharges internal drainage into the Deep Water Ship Channel and moves irrigation tailwater from waterways into the District irrigation system. The District is mostly agricultural. Most of the land in the District is primarily for row crop production. A marina with several businesses is also located on the Sacramento River side of the District. 429
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Figure 3-79: Reclamation District 765
Source: KSN Engineers
The South River Pump Station is located at the northern end of the District and is vulnerable to a levee failure. This station services areas in the City of Sacramento, the City of Citrus Heights, the City of West Sacramento, and unincorporated areas in the County of Sacramento. A project to construct a new 200-year flood protection levee around the pump station is estimated to begin in summer 2016.
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Sacramento Maintenance Yard (SMY) is part of the California Department of Water Resources’ Flood Maintenance Office and is charged with the maintenance and flood fight of State Maintenance Area and State-Maintained levee systems within its area of operations. While the SMY is physically located in Sacramento, it maintains discrete levee systems in Sutter, Sacramento, and Yolo Counties. Within Yolo County, SMY maintains and operates levees along Cache Creek, Putah Creek, Willow Slough Bypass, and the Yolo Bypass. A summary of the different creeks and bypasses and their associated flood protection systems follows.
Huff’s Corner - The Huff’s Corner Levee (along the south side of Cache Creek) is 0.29 miles long, but the county is not resourced for ownership and maintenance. Yolo County has no funding for ownership and maintenance of the Huff’s Corner Levee. The State owns and maintains the levee on either side of this 0.29-mile segment but provides no resources to the County for ownership and maintenance of Huff’s Corner. There has been some discussion between Yolo County and DWR about the State possibly taking over ownership and maintenance. Rate increase associated with the NFIP will most likely affect residents of Knights Landing within the next year. These increases can be an economic hardship on the rural areas and small communities in Yolo County, many of which are economically disadvantaged.
LOCATION AND EXTENT
California has over 13,000 miles of levees that protect residential and agricultural lands. The levee failures resulting from Hurricane Katrina prompted the State and the Department of Water Resources (DWR) to initiate development of a state-of-the-art California Levee Database (CLD) for the purpose of better understanding and managing levees in California. The CLD is an efficient tool for assessing levee reliability risk factors using a GIS-enabled geospatial database.
Starting in 2005, partnering with the Federal Emergency Management Agency (FEMA) under the auspices of FEMA's Map Modernization Management Support program, DWR has started assembling critically needed levee information on ownership, location, and risk assessment factors for all the levees in California. Recognizing that other agencies are engaged in similar efforts, DWR is actively participating on national committees organized by the Federal Emergency Management Agency (FEMA) and the U.S. Army Corps of Engineers (USACE) to ensure compatibility and coordination with other national efforts. Currently, the California Levee Database has location information for more than 10,000 miles of levees and flood control structures throughout California. In addition to the database above, the Yolo County Flood Insurance Study dated 5/16/2012 lists the levees in Yolo County and are detailed below.
Table 3-32: Levees in Yolo County
Community Flood Source
Levee Inventory
Identification # USACE Levee
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Yolo County (Unincorporated
Areas)
Buckeye Creek Not specified No
City of Woodland
Yolo County (Unincorporated
Areas)
Cache Creek 52, 53, 55, and 81 Yes
City of Woodland
Yolo County (Unincorporated
Areas)
Colusa Basin Drainage
Canal
94, 95, and 163 Yes
Yolo County (Unincorporated
Areas)
Knights Landing
Ridge Cut
83, 84, 120, 121,
and 162
Yes
City of Woodland
Yolo County (Unincorporated
Areas)
Old River 85, 118, and 119 No
City of West Sacramento
Yolo County (Unincorporated
Areas)
Sacramento River 11, 17, 86, 93, 122,
133 through 142,
147, 151, 152, 157,
and 168 through 171
Yes
City of West Sacramento
Yolo County (Unincorporated
Areas)
Sacramento River Toe
Drain
148 and 149 Yes
City of Davis
Yolo County (Unincorporated
Areas)
South Fork Putah
Creek
29, 30, 105, and 106 Yes
Yolo County (Unincorporated
Areas)
Unnamed Canal
between
Colusa Basin Drainage
Canal and Sacramento
River near El Dorado
Bend
123 and 124 No
Yolo County (Unincorporated
Areas)
Willow Slough 36 No
City of Davis
Yolo County (Unincorporated
Areas)
Willow Slough Bypass 34 and 35 Yes
City of Davis
Yolo County (Unincorporated
Areas)
Yolo Bypass 28, 82, 116, 117,
128, and 132
Yes
Yolo County (Unincorporated
Areas)
Yolo Bypass 5 No
Source: Yolo County Flood Insurance Study 2012
Yolo County has approximately 215 miles of project levees, managed by various agencies, including the County, 13 reclamation districts, one levee district, one drainage district, and DWR. These levees provide flood protection to West Sacramento, Woodland, Knights Landing, Clarksburg, Davis and important agricultural lands. In addition, the Yolo Bypass, the Sacramento Weir, and the Fremont Weir help protect Sacramento and other urban communities in the region from flooding by the Sacramento River. Some levees, particularly the project levees that protect parts of the City of Woodland and unincorporated Yolo County, the vicinity of Cache Creek and the town of Yolo only provide a 10-year level of flood protection rather than the 100-year federal standard. 432
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Without work to improve these levees, additional development in Yolo County’s floodplain could put more residents at risk of flooding hazards. The geographic extent of a Levee failure is Extensive with more than 50 percent of the operational area potentially being affected by a failure of any major levee. Parts of the County would be completely inundated.
The local levees have been assumed to provide adequate protection since their acceptance into the Sacramento River Flood Control Project in 1917, with the levees being modified over the decades. Recently, where insufficient geotechnical information exists to evaluate the integrity of the levees, DWR has taken the position, in conjunction with FEMA that levees are not certified. DWR has completed geotechnical evaluations of the urban Sacramento River Flood Control Project levees within the county and has proposed to do additional evaluations of nonurban levees in the coming years.
Figure 3-80 shows the extent of those areas that are protected by decertified levees and are currently subject to flooding. This map uses the best available information to identify those areas where flooding would be more than three feet deep if a project levee were to fail, assuming maximum capacity flows. Not surprisingly, levee flood protection zones are concentrated in eastern Yolo County, in areas adjoining levees for lower Cache Creek, Putah Creek, the Colusa Basin Drain, the Yolo Bypass, and the Sacramento River. Affected communities include Clarksburg, Davis, Knights Landing, West Sacramento, Woodland, and Yolo.
Also, as part of FEMA’s Map Modernization program, FEMA is mapping levees within communities, with a primary focus on maps determined to provide a 100-year level of flood protection. In August of 2005, FEMA Headquarters issued Memo 34 Interim Guidance for Studies Including Levees. This memo recognizes the risk and vulnerability of communities with levees. The memo mandates the inclusion of levee evaluations for those communities that are undergoing map changes such as the conversion to DFIRMs. No maps can become effective without an evaluation of all levees within a community against the criteria set forth in 44 CFR
65.10 Mapping of Areas Protected by Levee Systems. Generally, these levee certification requirements include evaluations of freeboard, geotechnical stability and seepage, bank erosion potential due to currents and waves, closure structures, operations and maintenance, and wind wet and wave run-up. In short, these guidelines require certification of levees before crediting any levee with providing protection from the 1 percent annual event (e.g., the 100-year flood).
In Yolo County, like other locations in California, levees and flood control facilities have been built and are maintained variously by public and private entities, including water, irrigation and flood control districts, other state and local agencies, and private interests. Some of these facilities were constructed with flood control as secondary or incidental to their primary 433
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purpose, so are not considered as providing protection from the 100-year or greater flood.
Levees in the County are discussed in the Levee Section of this plan.
Figure 3-80: Levee Protection Zones in Yolo County
Source: Yolo County General Plan
In the winter of 2017, a series of severe winter storms and the subsequent releases of water from dams upstream of Yolo County caused a number of damages throughout levees in the Yolo County Operational Area. Though no levees failed, there was significant sloughing and erosion to levees along the Sacramento River (including RD 1600, 827, 108, and CSA 6), Yolo Bypass (RD 2035), the Deepwater Ship Channel (RD 900), and Elk Slough (RD 150).
PAST OCCURRENCES
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There have been no disaster declarations related to levee failure in Yolo County, as shown on Table 3-5. The County had no USDA disaster declarations since 2012 related to levee failure, as shown on Table 3-7. There have been no NCDC levee failure events in Yolo County.
LIKELIHOOD OF FUTURE OCCURRENCE
Likely - Yolo County remains at risk to levee breaches/failures from numerous levees under a variety of ownership and control and of varying ages and conditions. Given the number and types of levees in and around the County, the potential exists for future levee issues in Yolo County. Due to deteriorating conditions on several levees in Yolo County, the probability of a catastrophic levee failure that would impact Yolo County and its jurisdictions is Likely:
Between 10 percent and 100 percent chance of occurrence in next year or has a recurrence interval of 10 years or less.
CLIMATE CHANGE AND LEVEE FAILURE
In general, increased flood frequency in California is a predicted consequence of climate change.
Mechanisms whereby climate change leads to an elevated flood risk include more extreme precipitation events and shifts in the seasonal timing of river flows. This threat may be particularly significant because recent estimates indicate the additional force exerted upon the levees is equivalent to the square of the water level rise. These extremes are most likely to occur during storm events, leading to more severe damage from waves and floods.
VULNERABILITY ASSESSMENT AND IMPACTS
Vulnerability – Medium
Levee failure flooding can occur because of partial or complete collapse of an impoundment, and often results from prolonged rainfall and flooding. The primary danger associated with dam or levee failure is the high velocity flooding of those properties downstream of the breach. Impacts from this include property damage, critical facility damage, and life safety issues. A levee failure can range from a small, uncontrolled release to a catastrophic failure. Vulnerability to levee failure is generally confined to the areas subject to inundation downstream of the facility.
Secondary losses would include loss of the multi-use functions of the facility and associated revenues that accompany those functions. Numerous areas of Yolo County are susceptible to levee failure depending on where a breach may occur. These vulnerabilities are mentioned in the profiles above for each Reclamation District and Local Maintaining Agency.
Levee failure flooding would vary depending on which structure fails and the nature and extent of the failure and associated flooding. This flooding presents a threat to life and property, 435
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including buildings, their contents, and their use. Large flood events can affect lifeline utilities (e.g., water, sewerage, and power), transportation, jobs, tourism, the environment, agricultural industry, and the local and regional economies.
The overall impact to the community from levee breach or failure includes:
• Injury and loss of life.
• Commercial and residential structural damage.
• Disruption of and damage to public infrastructure.
• Health hazards associated with mold and mildew.
• Damage to roads/bridges resulting in loss of mobility. • Negative impact on commercial and residential property values. • Long dewatering periods.
• Significant disruption to students and teachers as temporary facilities and relocations would likely be needed.
FUTURE DEVELOPMENT TRENDS & POPULATION PATTERNS
There have been several projects to address levee failure in Yolo County. In addition to the General plan addressing flooding hazards through land use policies and zoning, the flood protection boards, reclamation districts, and Yolo County’s Department of Natural Resources, proposes various developments to improve our existing levee systems. These projects, when implemented, would decrease Yolo County’s vulnerability to levee failure.
Some development projects since the last 2018 HMP update include:
Conaway Levee Setback and Transitory Storage Project: The 2017 CVFPP identified the potential setback of the west levee of the Yolo Bypass to provide additional flood protection for lands within the City of Woodland and Yolo County, and to provide transitory storage of water during flood events in the Yolo Bypass. The Conaway Levee Setback Transitory Storage Project would include degrading a portion of the existing Yolo Bypass west levee, constructing a weir outlet and culverts in the west levee and constructing two setback levees, one extending southwest from Interstate 5 and one extending west from just north of the Davis wetlands.
Preliminary planning has been conducted for this project.
Sacramento River Right Bank Levee Improvement Project: The proposed Sacramento River Right Bank Levee improvements would address under-seepage, through-seepage, stability, and freeboard deficiencies. To address under- and through-seepage, from levee mile
0.0. to 0.75 adjacent to the community of Knights Landing, an 80-foot-deep clay cutoff wall would be installed through the center of the existing Sacramento River Right Bank Levee. The 436
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construction area would extend approximately 0.75 miles along the Sacramento River Right Bank Levee. Additional improvements along the Sacramento River Right Bank Levee are proposed downstream of Knights Landing to address seepage. Seepage areas would be addressed by either constructing seepage stability berms or cutoff walls. For the construction of cutoff walls, the existing levee would need to be degraded by half its height for the installation of the cutoff wall, and then rebuilt. Large earthmoving construction equipment would be used to complete the improvements. The levee will be reconstructed to meet current levee standards and attain a 100-year design surface water elevation. The construction work area would include an access corridor on the landside toe of the existing levee. All construction staging and material stockpiling would occur along the levee as construction progresses down the levee and would take place within the construction work areas. Access to the construction work areas would be from the levee or County Road 116B. The construction work area would include an access ramp up onto the existing levee. No residents would be displaced as a result of the proposed seepage improvements. While some private parcels may be affected, no buildings or structures would be removed.
Knights Landing Ridge Cut Improvement Project: The proposed Knights Landing Ridge Cut improvements would occur southwest of Knights Landing and would include clearing and grubbing of trees and vegetation, excavating the face of the existing landside levee slope, and reconstructing the levee with imported fill to widen the levee crown and create a consistent elevation along the levee. The proposed improvements on the landside of the Knights Landing Ridge Cut Levee would also include remediation of existing levee encroachments, including but not limited to removal of levee pipe penetrations, relocation of PG&E power poles, and replacement of levee gates. The finished levee crown elevation would be reconstructed a minimum elevation of 43 feet.
Large earthmoving construction equipment would be used during construction. The proposed improvements can be accessed via existing levee ramps and temporary earthen ramps. Proposed haul routes include Locust Street and existing agricultural/farm roads. These access routes would be used by two-way traffic. The proposed haul routes are currently used as agricultural roads and may require grading or crushed rock surface to be placed in order to support construction vehicles. Construction staging areas would be located, to the extent practicable, away from sensitive resource areas and known cultural resources. Construction staging and material stockpiling would occur along the levee as construction progresses down the levee. A wider area within the northwest portion of the proposed construction area would likely be used for parking construction trailers and vehicles. No residents would be displaced as a result of the proposed improvements to the Knights Landing Ridge Cut Levee. While some private parcels may be affected, no buildings or structures would be removed. 437
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Portuguese Bend Multi-Benefit Enhancement Area: The Portuguese Bend multi-benefit enhancement area would protect and restore habitat in line with the objectives of the CVFPP 2017 Update within an approximately 136-acre area located between the levees of the Sacramento River known as Portuguese Bend. Situated southeast of Knights Landing and along the eastern perimeter of the Knights Landing Basin, the habitat improvements within Portuguese Bend include controlling invasive plant species, planting native species, and implementing an ongoing management and monitoring program. The native species to be planted would replicate and enhance the existing native habitat within the area including the existing mixed riparian forest, riparian willow forest, emergent marsh, and tule marsh plant communities. The planting would be implemented appropriate to the site’s topography and hydrology to ensure the long-term viability of the enhanced plant communities. The use of heavy equipment is not anticipated; passenger vehicles and light trucks would be used to facilitate planting. Access to the work areas would be from County Road 116B. Staging would occur either on top of the levee or on the exposed areas and dirt roads that are located on the site. No residents would be displaced because of the proposed freeboard and seepage improvements. While some private parcels may be affected, no buildings or structures would be removed.
If there is an increase in populations living in potential flooding areas from levee failure, there would be an increase in the impact of levee failures to these areas and populations. However, land use policies and regulations tend to discourage development in levee failure prone areas.
Those policies and regulations coupled with mitigation measures to mitigate impacts and existing vulnerabilities to levee failure would decrease the impact and vulnerability levee failure has on population growth.
3.11 WILDFIRE
Although wildfires can occur in any state, they are most common in the Western states including California where heat, drought, and thunderstorms create perfect wildfire conditions. California is recognized as one of the most fire-prone and consequently fire-adapted landscapes in the world. The combination of complex terrain, Mediterranean climate, and productive natural plant communities, along with ample natural and aboriginal ignition sources, has created conditions for extensive wildfires. A wildfire is a fire that occurs in an area of combustible vegetation. The three conditions necessary for a wildfire to burn are fuel, heat, and oxygen. Fuel is any flammable material that can burn, including vegetation, structures, and cars. The more fuel that exists and the drier that fuel is, the more intense the fire can be. Wildland fire is an ongoing concern for the Yolo County Operational Area. Generally, the fire season extends from June through October of each year during the hot, dry months; however, recently the fire season has 438
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been nearly year-round. Fire conditions arise from a combination of high temperatures, an accumulation of vegetation, low humidity, and high winds. Wildland fires that burn in natural settings with little or no development are part of a natural ecological cycle and may be beneficial to the landscape.
Wildfires can be started naturally through lighting or combustion or can be set by humans.
There are many sources of human-caused wildfires including arson, power lines, a burning campfire, an idling vehicle, trains, and escaped controlled burns. On average, four out of five wildfires are started by humans. Uncontrolled wildfires fueled by wind and weather can burn acres of land and everything in their path in mere minutes and can reach speeds up to 15 miles per hour. On average, more than 100,000 wildfires burn 4 to 5 million acres of land in the United States every year.
Wildfires are of primary concern when they occur in the Wildland Urban Interface (WUI), which is defined as areas where homes are built near or among lands prone to wildfire. Most structures in the WUI are not destroyed from direct flame impingement, but from embers carried by wind.
With continued growth in the WUI throughout California, wildfire risk will only increase. Much of the County’s rural residential land is in the WUI, especially along the western edge. Only four percent of Yolo County lands are within the jurisdictional boundaries of its cities; most of the population resides in these cities.
LOCATION AND EXTENT
Wildfire danger varies throughout Yolo County. The County is characterized by relatively level valley floor landscapes to the south and east; this lack of topography and complex fuels leads to very little severe fire behavior. In the increasingly hilly landscapes rising to the north and west, the rugged topography creates a landscape where fires can spread rapidly upslope and access for suppression equipment is limited. The geographic extent of Wildfires is Limited having about 10-25 percent of the operational area potentially affected. A wildfire of 25,000 acres could occur in Yolo County.
The National Wildfire Coordinating Group (NWCG) developed a standard data class code for fire sizes, as shown in Figure 3-81 below.
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Figure 3-81: NWCG’s Fire Size Class Code
Source: NWCG.gov
Based on historical data and the total average acres burned in Yolo, the potential extent for wildfires that burn in Yolo would be assigned value H, 10,000 to 49,999 acres. More information on historical fires that have occurred in Yolo County (see Figure 3-82), and since the last update is further discussed below.
A wildfire in the unincorporated area of Yolo County has potential to significantly impact the Capay Valley and could result in evacuations. Since the last plan update, there was the 2019 Sand Fire where there were road closures from Highway 16 to Highway 20 to the town of Brooks, in addition to the evacuation of residents living along County Road 41. Large fires along State Route 16 can impact local resources and access to the communities along the highway. And in 2020 there was the LNU and Santa Clara Unit Complexes which were the largest fires recorded in California History. These fires caused more road closures and evacuations. The Yocha Dehe Casino is a large economic asset to the area. Grass fires are also of concern in the unincorporated areas of the county. A 10-acre grass fire in Dunnigan in 2016 destroyed a house, and the Hardwoods Subdivision is of particular concern for a grass fire.
To quantify the potential risk from wildfires, the California Department of Forestry and Fire Protection (Cal Fire) has developed a Fire Hazard Severity Scale which uses three criteria in order to evaluate and designate potential fire hazards in wildland areas. The criteria are fuel loading (vegetation), fire weather (winds, temperatures, humidity levels and fuel moisture contents) and topography (degree of slope). According to the Cal Fire wildfire severity map for Yolo County (see Figure 3-83), the western portion of the county, west of Esparto and Winters, is designated as a Very High Fire Severity Zone (VHFSZ). 440
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Figure 3-82: Historical Fires Greater than 5,000 Acres since 2000 Source: CalFire; Yolo County GIS, Map updated:12/10/2021 441
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Figure 3-83: Fire Hazard Severity Zones in Yolo County
Source: CalFire
The VHFSZ in Yolo County is in a State Responsibility Area (SRA), meaning that fire suppression is under the control of the State Department of Forestry and Fire protection (Cal Fire). The USGS has also designated these areas as having high wildfire potential (see Figure 3- 84). Areas with higher wildfire potential values represent fuels with a higher probability of experiencing extreme fire behavior under conducive weather conditions such as wind, Yolo County is circled below.
Figure 3-84: Wind-enhanced Wildfire Potential in Yolo County Source: USGS
The County and its municipalities fight many vegetation fires, particularly during the summer.
These fires tend to occur along major highways and railroads, and usually do not damage 443
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structures. However, fires can be exacerbated by hot north winds during periods of extremely low humidity. In addition, if they are fed by dry grass and vegetation they can easily grow out of control. Wildfire can damage structures and facilities, and the County must be prepared for protection from dangerous wildfires, especially in the WUI where urban and non-urban landscapes meet.
Yolo County is in the Sonoma-Lake-Napa Unit (LNU), one of twenty-one (21) California Department of Forestry and Fire Protection (CAL FIRE) administrative units. The Unit was created in 1996 with a merger of the then Sonoma Ranger Unit, and the Lake-Napa Unit. It is comprised of the six counties of Sonoma, Lake, Napa, Yolo, Colusa, and Solano. LNU has primary responsibility for more than 2.3 million acres of CAL FIRE Direct Protection Area (DPA) lands, more than any other unit. It has the third largest population living within CAL FIRE DPA and ranks third in average number of annual fires. The Unit is divided into four divisions and ten field battalions. The boundaries of Sonoma County define the West Division with four battalions. The South Division is defined by Napa County and has three battalions.
The North Division encompasses Lake County and has two battalions. The East Division consists of Yolo, Solano, and Colusa Counties and has two battalions.
There is a wide range of fuels in the East Division. Fuels range from agricultural farmland (wheat, safflower, cut stubble), annual grasses, oak woodland, 15 – 50-year-old chaparral, large stands of decadent brush and timber in the higher elevations of the battalion. Due to aggressive fire suppression tactics and lack of aggressive wildland fuels management, both the vertical arrangement and horizontal continuity of fuels, have and will promote rapid fire growth. These same conditions will also hinder conventional fire suppression tactics. Critical concerns are when the chaparral dead-to-live ratio exceeds 50%, and live fuel moisture approaches 60% in late summer and early fall. Ten-hour fuel moistures average from 4-7, dropping to 3 quite often.
The weather is generally warm and dry in this area during the day with a slight relative humidity recovery at night. If a critical weather pattern exists such as a Foehn North Wind, or a cold front passage, the daily diurnal weather variation will be subdued. If these critical weather patterns align with the topography, expect extreme rates of spread, especially along exposed ridges and through constricted areas. Peak summer day temperatures in Yolo County are generally 95°- 105°F, cooling to 50°-60°F at night, with relative humidity ranging between 20% – 35% or less.
Gradient winds are generally out of the N/NW 5-10 mph, strengthening in the afternoon with a 10-15 mph wind in the late afternoon diminishing by dark. Strong evening (2100- 0200) winds do occur occasionally in the Capay Valley with normal winds (down slope/down valley) after dark as the flow reverses. There is a Remote Automated Weather Station (Brooks RAWS) 444
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located at Brooks Fire Station. The station gives a good indication of current weather conditions.
It can be accessed at http://raws.wrh.noaa.gov/roman/.
Elevation within the East Division ranges from 250’ to 3000’ with slopes ranging from 0 – 80%.
There are two dominant North/South orientated ridges: Blue Ridge, running from the Yolo/Solano County line north to Rumsey Canyon and Walker Ridge, running from Hwy 20 to central Colusa County. These main ridges keep the coastal influence weather from being a factor. There are also two smaller ridges that can play a significant role in fire spread: Capay Hills and Cortina Ridge. Farmlands, ranches, rural and major roads along with other manmade features provide a network of barriers that will need to be connected to create an effective fire line. Capay Valley and Bear Valley are wide valleys that provide the opportunity for wind to be funneled even under local wind conditions; this situation will be compounded during critical weather conditions.
Having similar characteristics occurring simultaneously during wildfires and extreme heat events, the greatest effect extreme heat and wildfires has within the Yolo County Operational area is the population, as well as the County’s agricultural industry. Heat can cause stress to agricultural crops and livestock in the County. Though crops in Yolo County area adaptable to heat, they can become vulnerable to prolonged periods of high temperatures. Extreme heat also dries out vegetation in the County, creating greater risks from wildfire. When combined with low humidity, high winds, and extreme heat, it can contribute to the start and spread of wildfires.
Most wildfires in Yolo County are quickly contained due to rapid reporting and response, but if this first effort fails, a wildfire can get very big very fast. Such fires can require extensive firebreaks and/or a weather change for containment. There have been several notable wildfires in Yolo County, particularly since the last plan update. See the Unincorporated Yolo County Community Profile for a map of historical wildfires in Yolo County. • 09/28-09/30/1999 - The Rumsey Incident was responsible for burning 3,015 acres (Fire Size Class Code F). Fire suppression costs approached 1 million dollars. Six injuries and zero deaths were reported. The fire threatened structures and closed Highway 16 from Rumsey to Highway 20. Erratic winds and steep terrain prolonged the control process. • 07/04-07/12/2014 – Monticello Fire: The Monticello Fire was started by fireworks on the southeast shore of Lake Berryessa and burned 6,488 acres (Fire Size Class Code G) before it was fully contained. Five firefighters suffered minor injuries, including heat exhaustion, while fighting the blaze. Erratic wind shifts led to extreme fire behavior during the first few days of the fire, prompting evacuation orders for 40 homes in Golden 445
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Bear Estates near Winters. No structures were lost in the fire. • 07/22-08/05/2015 – Wragg Fire: The Wragg Fire was started by an idling car on State Route 128 near Lake Berryessa. The fire burned 8,051 acres (Fire Size Class Code G) and destroyed two buildings. Parts of Interstate 505 in Yolo County were closed during the fire. Mandatory evacuations were ordered for 136 homes, including Golden Bear Estates near Winters. No injuries were reported.
• 07/29-09/14/2015 – Rocky Fire: The Rocky Fire was started by a faulty gas-powered water heater inside an outbuilding being used for an illegal marijuana grow in Lake County. The fire burned 69,438 acres (Fire Size Class Code I) in Yolo, Lake, and Colusa Counties and destroyed 43 homes and 53 outbuildings. Several hundred people were evacuated in Lake County, but no injuries were reported. Yolo County was considering evacuating Capay Valley if the fire crested the Blue Ridge Mountains, but it did not. The Rocky Fire eventually merged with the Jerusalem Fire.
• 08/09-08/25/2015 – Jerusalem Fire: The Jerusalem Fire was human caused and burned 25,118 acres (Fire Size Class Code H) in Lake County on the outskirts of Yolo County before it merged with the Rocky Fire. The fire destroyed six homes and 21 outbuildings.
Evacuations were ordered in Lake County, but no injuries were reported. • 08/02-08/11/2016 – Cold Fire: The Cold Fire was a human caused wildfire that burned 5,371 acres (Fire Size Class Code G) in Yolo County near Lake Berryessa. The fire destroyed two buildings and caused an estimated $100,000 in damage. The Cold Fire burned primarily in the footprint of the Monticello Fire. Mandatory evacuations were ordered for Canyon Creek Campground and Golden Bear Estates near Winters. • 07/06-07/11/2017 – Winters Fire: The Winters Fire was a human caused wildfire that burned roughly 2,300 acres (Fire Size Class Code F) in the Cold Fire footprint north of State Route 128. The fire did not damage any structures, but one firefighter was injured, and Golden Bear estate was evacuated for the fourth year in a row. • 06/08-06/17/2019 - On June 8, conditions were favorable for wildfire growth as relative humidity values fell into the teens and northerly winds gusted up to 25-45 mph. Prior to the start of this event, the local utility company decided to de-energize power lines per CA Public Utility Commissions (CPUC) Public Safety Power Shutoff (PSPS) guidelines.
Eventually, a fire did start at 1350PST in Yolo County, which became known as the Sand Fire. There were 2512 acres (Fire Size Class Code F) of land burned over a period of 8 446
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days, along with 7 structures destroyed. The fire also led to road closures from Highway 16 to Highway 20 to the town Brooks in addition to the evacuation of residents living along County Road 41.
• 08/17-08/31/2020 - During mid-August, moisture from tropical storm Fausto moved along the coast of southern CA and made landfall over central and northern California.
This system, combined with an oppressive high-pressure system that had predominately dry air, caused widespread dry thunderstorms to develop. Thousands of lightning strikes occurred overnight, which combined with the critical dry fuels, led to massive wildfire development. The August, the North, the LNU, and Santa Clara Unit (SCU) Complexes all started between August 15 and 17. The LNU Complex started on August 17 and will eventually become contained on October 2, 2020. This fire ends up burning a total of 363,220 acres (Fire Size Class Code J), destroying 1491 structures, including an NWS COOP site, and damaging 232 structures, the largest fire recorded in California history.
Many evacuations occurred, including larger sized populations such as Fairfield, Vacaville, and Travis Air force Base. Yolo County was also affected by the fires and had evacuations and road closures. Multiple road closures happened as well, including Interstate 80 for a brief period. Per the last CalFire incident update, 6 injuries occurred, 4 were first responders and 2 were civilian. The fires burned caused significant damage over the area. The SCU Complex finally becomes fully contained on October 1, 2020 Though larger wildfires occur in the mountainous terrain of Yolo County, grass fires in the valley are more common and can cause significant damages to structures and agricultural lands:
On November 4th, 2013, a 200-acre (Fire Size Class Code D) grass fire burned near Esparto causing concern for residents, but no structures were destroyed.
On August 14th, 2014, a 369-acre (Fire Size Class Code E) grass fire burned near Winters after a car crashed into a field. No structures were threatened, and no evacuations were ordered.
A grass fire that occurred in Dunnigan on June 20, 2016, destroyed a home and burned property near a vineyard. A grass fire in Woodland on the same day burned several hay bales.
One destructive wildfire in Yolo County occurred in October 2006 when 11,000 acres (Fire Size Class Code H) of rangeland burned, destroying six vehicles, and damaging three to four houses plus 15 barns and outbuildings. More than 300 animals, mainly sheep, had to be put down as a result of injuries suffered when the fire roared across their pasture. The total animal death toll is estimated to top 500. No human lives were lost.
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On June 30th, 2018, The County Fire started in the community of Guinda and was contained on July 17, 2018, after burning 90,288 acres (141 sq mi; 365 km2) (Fire Size Class Code I). The fire caused mandatory evacuations along Highway 128, County Road 23, and areas around Lake Berryessa, including Monticello Dam and Golden Bear Estates near Winters. The fire destroyed 20 structures, damaged four, and caused one injury. The fire was started by an improperly installed electric fence for livestock.
PAST OCCURRENCES
Yolo County has had three Federal and two state disaster declarations from fire events and fire risk events, as shown in Table 3-27. The County has also had six USDA disaster declarations since 2012 related to wildfire and high fire risks.
Table 3-33: Yolo County State and Federal Disaster Declarations, 1965-2023 Year Disaster Name Disaster Type Disaster #
State
Declaration #
Federal
Declaration #
2013
Extreme Heat, High
Winds, High Fire Risk
Drought –
FAST TRACK
USDA Primary
S3569
8/21/2013 -
2014
Extreme Heat, High
Winds, High Fire Risk
Drought –
FAST TRACK
USDA Primary
S3637
1/23/2014 -
2014
Extreme Heat, High
Winds, High Fire Risk
Drought- FAST
TRACK
USDA
Contiguous
S3626
1/15/2014 -
2015 Wragg fire Fire FM-5091-CA - 7/23/2015
2015
Extreme Heat, High
Winds, High Fire Risk
Drought –
FAST TRACK
USDA Primary
S3784
2/4/2015
2016
Extreme Heat, High
Winds, High Fire Risk
Drought- FAST
TRACK S3952
USDA Primary
2/17/2016
2020
LNU lightning fire
complex Fire FM-5331-CA
8/18/2020 8/18/2020
2020 Wildfires Fire DR-4558-CA 8/22/2020 8/22/2020
2020 Wildfires Fire DR-4569-CA
USDA
Contiguous
10/16/2020
-
* Data from Table 3-5: Yolo County State and Federal Disaster Declarations, 1965-2023. All years that did not have wildfire or high fire risk declarations were removed.
The NCDC data showed 6 wildfire events for Yolo County since 1950, with two deaths, eight individuals injured and $500,000 in property damage. (see Table 3-34 below).
Table 3-34: NCDC’s Wildfire Events for Yolo County 1950-2/23/2023* Event Type
Number
of
Events Deaths Injuries
Property
Damage
Crop
Damage
Wildfire 6 2 8 $500,000 $0
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Totals: 6 2 8 $500,000 $0
*Data from Table 3-6: NCDC’s Wildfire events for Yolo County 1950-2/23/2023. All other event types were removed.
Between 2015-2018 several large wildfires have burned in the Blue Ridge Mountains between Yolo, Napa, and Lake Counties. They have included the 2014 Monticello Fire, the 2015 Wragg Fire, the 2015 Rocky Fire, the 2015 Jerusalem Fire, the 2016 Cold Fire, and the 2017 Winter Fire. See Figure 3-85 for a map of historic wildfires in Yolo County.
Figure 3-85: Historic Wildfires in Yolo County
Source: Yolo County GIS
LIKELIHOOD OF FUTURE OCCURRENCE
Highly Likely - The probability of future occurrences in the next 100 years is Highly Likely:
Near 100 percent chance of occurrence next year or happens every year. Wildfires have a higher chance of occurrence from May to October when the weather is warmer and drier.
CLIMATE CHANGE AND WILDFIRE
Climate change could affect fire behavior, ignitions, fire management, and vegetation fuels.
Warmer temperatures cause early runoff, which leads to longer and drier summer conditions, 449
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thus resulting in wildfires of greater frequency and duration. Hotter weather increases the incidence of lightning, which is the primary cause of wildfires in the United States. Climate change also could affect wind patterns that spread fires, making fires harder to contain. In addition, the increased prevalence of dry conditions provides greater opportunities for arson, which is another source of wildfire. Much of the coast range hills of Yolo County are considered to have a moderate to high risk of wildfire. Wildfire is a potentially significant risk to public health and safety. In addition to direct safety risks, wildfires can lead to immediate and longterm adverse public health problems due to smoke exposure. During wildfires, large populations can be exposed to a complex mixture of pollutant gases and particles, which can have both acute and chronic health effects. Smoke can irritate the eyes, harm the respiratory system, and worsen chronic heart and lung diseases, including asthma. People with existing cardiopulmonary diseases are generally at the greatest risk from smoke inhalation, with age being a complicating risk factor for the exposed population.
According to the U.S. Climate Resilience Toolkit modeling, Yolo County has a relatively low national risk index rating to Wildfire due to Climate change (see Figure 3-86).
Figure 3-86: Yolo County Hazard Report: Wildfire (page 3) Source: U.S Climate Resilience Toolkit
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VULNERABILITY ASSESSMENT AND IMPACTS
Vulnerability – High
The mountainous areas of the County are most vulnerable to large wildfire. While these areas are mostly unpopulated, the Capay Valley and the City of Winters are susceptible. Highway infrastructure, power lines, and public use facilities (including campgrounds) along State Routes 16 and 128 are vulnerable to wildfire. Cities and communities throughout the valley portion of the County can become susceptible to large grass fires, which can burn homes and businesses.
Populated highway corridors, particularly State Route 113 in Davis, are vulnerable to grass fire.
In Yolo County, there are very few homes and structures located in the mountainous areas where large wildfires typically occur. The primary impacts in these areas would be to outbuildings, campgrounds and day use areas along State Route 16 in the Cache Creek Canyon as well as along State Route 128. There are several small communities in Yolo County located in the WUI, including the Capay Valley towns of Rumsey, Guinda, Brooks, and Capay. Should a wildfire start in the Blue Ridge Mountains, these areas could potentially be impacted, and evacuations may be required. Homes and businesses could be lost, and there could be damage to vineyards and other agricultural areas. The City of Winters is also located close to the WUI. With the right wind conditions, a wildfire could potentially impact residents on the western side of the city and result in damaged or destroyed structures and evacuations. The business district of the city is located well enough away from the WUI that it should not be impacted. The community of Golden Bear Estates, which has been evacuated in three previous wildfires, is located directly in the WUI. A wildfire could burn through this area and result in the loss of homes and property.
A grass fire located in the valley of Yolo County could burn through agricultural land and could affect crops as well as animals. Grass fires also have the potential to destroy homes and other structures, as has occurred previously in Yolo County. Impacts to infrastructure from a wildfire in Yolo County would consist mainly of damage to power lines. A secondary impact from wildfires is smoke, which could affect breathing of certain at-risk populations throughout the County.
Wildfire Smoke and Air Quality
Wildfires pose immediate danger to lives and property, but poor air quality due to wildfire smoke and ash may lead to significant public health consequences that can persist for extended periods.
Wildfire smoke is a mixture of air pollutants of which particulate matter is the principal public health threat. Extensive scientific evidence has demonstrated health effects in response to shortterm particulate matter exposure ranging from eye and respiratory tract irritation to more serious 451
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effects, including reduced lung function, pulmonary inflammation, bronchitis, exacerbation of asthma and other lung diseases, exacerbation of cardiovascular diseases, such as heart failure, and even premature death.
Since the 2018 HMP, significant wildfires occurring in nearby counties have created significant air pollution affecting area residents. County residents have had to breathe wildfire smoke, from fires both within and outside of the County causing on a broad range of health effects of wildfires smoke, including visits to hospital emergency departments, hospitalizations, medication prescribing, and emergency ambulance dispatches. Although most healthy adults and children will recover quickly from wildfire smoke exposure, there are certain groups that are more susceptible to the effects of wildfire smoke. These groups include children, people over 65, pregnant women, people with pre-existing pulmonary or cardiovascular conditions, people of lower socioeconomic status, and outdoor workers. These sensitive sub-populations represent a significant percentage of the total population. As wildfire smoke research advances, it is likely that other groups will be added to the list of impacted subpopulations. Some people may experience immediate health impacts while others may experience health impacts that manifest days or weeks later, depending on the underlying sensitivity.
Air quality standards have been established to protect human health with the pollutant referred to as PM2.5 which consists of particles 2.5 microns or less in diameter. These smaller sizes of particles are responsible for adverse health effects because of their ability to reach the lower regions of the respiratory tract.
To help mitigate the smoke and air pollution during wildfire or similar health harming events, the Yolo-Solano Air Quality Management District’s (YSAQMD) mission is to protect human health and property from the harmful effects of air pollution. They seek to achieve that goal in all their work, from rulemaking to permitting, from enforcement to public education, from planning to monitoring. They consider themselves as an essential part of the community, and as such, working closely with local businesses to find sensible solutions to their needs while enforcing their own rules about emissions and control technology. Yolo-Solano has a rich agricultural heritage and works with farmers every day to ensure their work doesn’t impair the air quality.
Their monitoring network provides real-time data that allows the district to forecast air quality and issues advisories to the public as needed. The monitoring network also allows the district to show progress toward air quality standards. Currently, there are six permanent monitoring sites within Yolo-Solano (see Figure 3-87).
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Figure 3-87: Yolo – Solano Air Quality Management District – Air Quality Monitoring Sites Source: Yolo-Solano Air Quality Management District
During the summer months when high levels of smog or smoke are reported, Spare The Air alerts are sent out to notify registered participants of the unhealthy air quality levels in their areas, and provide them information on ways to ways to reduce air pollution and protect themselves. These alerts are issued when the AQI for ground-level ozone is forecasted to be 126 or above. Residents in the region are encouraged to continue to telework, take transit, drive a hybrid or electric vehicle, or consider active transportation options such as walking, biking, or riding a scooter when possible, to help continue to improve air quality in the region. The AQI table is shown below, Figure 3-88.
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Figure 3-88: Air Quality Index Values
Source: Environmental Health Services, USF
A useful tool developed by the U.S. Environmental Protection Agency to communicate information about air quality to the public is the Air Quality Index (AQI). The U.S. EPA’s AirNow website, https://www.airnow.gov, displays air quality data by zip code using the AQI to indicate air quality values. The AQI uses a 6-level color-coded scale to communicate the health impacts of pollution at different concentration ranges (Green, Yellow, Orange, Red, Purple and Maroon). Each color-coded level has an associated descriptive term, progressing from “Good” to “Hazardous.”
Wildfires lead to smoke production and many California communities have experienced sustained, elevated AQI values during recent wildfires. Public Health, in partnership with other appropriate County agencies will take the lead in developing and sending appropriate public messages regarding air quality health concerns.
Access and Functional Needs Individuals
During a mass wildfire event, the evacuation of people with disabilities and access and functional needs poses additional requirements with respect to alert and notification, information dissemination, evacuation, emergency transportation, and sheltering requirements.
Many people with disabilities are completely self-sufficient and may be prepared to evacuate an area caused by wildfire. Other potentially at-risk individuals include those with cognitive or emotional disabilities that may impair their ability to make decisions during an emergency and should be transported with their caregivers or other mental health professionals when possible. 454
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It is critical that modes of available transportation are identified that can accommodate people with disabilities and other access and functional needs during an evacuation. Transportation that can accommodate people who use wheelchairs, power chairs, service animals, or other mobility equipment aids needs to be made available. Some potential options can be the use of liftequipped school buses or vans.
Yolo County HHSA maintains a database of registered persons with access and functional needs, as well as a list of facilities where persons with access and functional needs are housed. If needed, law enforcement will work closely with Yolo County HHSA and the local EOC on the evacuation of persons with access and functional needs during a mass wildfire event.
Wildfire and Power Shortage/PSPS
During periods of wildfire (or during periods of elevated risk due to high temperatures, low humidity, and high winds), PSPS events may be declared in the County. The PG&E PSPS Plan’s aim is to reduce accidental fires set by downed or compromised powerlines during elevated wildfire weather conditions by effectively cutting off the power to areas servicing structures in the wildland interface. AFN populations and those who rely on electric power to continue daily home or work operations may find themselves without power for two to seven days after a Red Flag Warning event or in other cases when PG&E determines there is a substantial risk to the community.
In the event of a PSPS, notification measures are in place to support the affected communities due to lack of power, power outage frequency, and duration of the outage. As a result, in the event of spontaneous evacuations, evacuees may need to be directed to shelters, cooling centers, community centers, or any designated public gathering locations. Length of time to reenergization will depend on how large of an area is impacted, and how much damage has occurred to PG&E’s electrical infrastructure. Emergency management and local government personnel should be prepared to support the community for extended durations of time. More information and power shortage and failure can be found at the beginning of Section 3.2.3.
FUTURE TRENDS IN DEVELOPMENT & POPULATION PATTERNS
Yolo County’s land use, building code, and zoning ordinances regulate urbanization into wildland areas which can alter natural fire regime. The County is responsible for implementation of State wildfire prevention and mitigation policies. In the County’s General plans existing County building requirements, such as requiring sprinklers in residential structures, are designed to address fire risks to County residents. There are policies in place in which the County communicate the risks, requirements, and options available to those who own land and live in wildfire hazard areas. Specific actions in the General Plan would further aid wildfire response and minimize loss of life and property in fires through construction requirements for new 455
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buildings, emergency access requirements, and establishment of “defensible space”. As the planning area experiences future growth, it is anticipated that the exposure to this hazard will remain as assessed due to these capabilities. As a result of some of the land use requirements and building codes, population patterns would not affect the vulnerability or impact of wildfires to Yolo County. Even if development moves from urbanized areas to wildland areas due to population growth, the land use development codes would mitigate the vulnerability or impact of wildfires.
FUTURE CLIMATE INDICATORS
According to the Climate Resilience Toolkit modeling (Figure 3-86), future climate indicators on wildfire predicts that the maximum temperature days above 90℉ and above 100℉ may increase by 2099. Hotter temperatures have the potential to create larger, more frequent fires which would impact vulnerable populations, and identified facilities and community assets. Natural or current fire patterns could change, resulting in more frequent or higher intensity burns, more acreage burned, more unpredictable patterns, making fire suppression more difficult and could jeopardize facilities and community assets that may not have been previously at risk. Additional increased fire risk would continue to have secondary impacts on air quality, of which would exacerbate the effects of poor air quality on vulnerable populations. Future Climate change would negatively impact vulnerable populations and put more stress on facilities and community assets, especially as it increases wildfire risk and air quality.
3.12 YOLO COUNTY OPERATIONAL-AREA PROBLEM STATEMENTS
Problem Statements are statements of particular interest regarding primary hazards, geographic areas of concern, or vulnerable community assets. As part of the planning process, the Steering Committee identified key vulnerabilities and hazards of concern applicable to the entire County.
Hazard Problem Statements helped the Steering Committee identify common issues and weaknesses, determine appropriate mitigation strategies, and understand the resources needed.
The Countywide Hazard Problem Statements were based on risk assessments, risk prioritization processes, vulnerability analysis, local knowledge, jurisdiction-specific problem statements, and community and stakeholder input. For the countywide plan, High and Moderate risk hazards were included in problem statements and countywide mitigation actions. Countywide Hazard Problem Statements are identified below:
Levee Failure
There are several levees throughout Yolo County used to control flooding. Although mitigation work has been done on several levees, a levee failure could place people, property, and the agricultural industry at risk. In addition to damaging property, infrastructure, trees, and other 456
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large objects, levee failure can result in significant water quality and debris disposal issues.
Severe erosion is also a consideration.
Wildfire
California, and subsequently Yolo County, is in a cycle of extreme heat, drought, and fire, all amplified by climate change. Wildfires are a natural part of the California environment; however, fire behavior has increased in frequency, size, and impact from longer wildfire "seasons." Deferred vegetation management and population sprawl in the wildland-urban interface and intermix have increased the probability and impact of wildfires.
Drought & Water Shortage
In Yolo County, water supply is extremely limited during non-drought years. As such, droughts are a serious threat in the County and could devastate the agricultural industry, a major economic driver and job provider. Additionally, prolonged periods of drought can reduce water available for residential users and increase water prices. Governing authorities have been established to limit water use and protect water supply. Water credits/rights procurement may limit new development necessary to meet increasing housing demands. Periods of drought also lead to increased pumping of groundwater wells, which can exacerbate seawater intrusion into the aquifer, increase land subsidence risks, and affect water quality. Contamination of drinking water, though unlikely, could be catastrophic. Drought conditions are likely to increase in future climate change scenarios.
Severe Weather: Extreme Heat
Extreme heat can be dangerous to anyone without proper hydration or cooling, and can trigger health conditions such as heat exhaustion, heat stroke and respiratory problems. High temperatures contribute to the build-up of harmful air pollutants which impact vulnerable populations such as the elderly, children, pregnant women, people with access and functional needs, outdoor and agricultural workers, and homeless/transient populations. Extreme heat has disproportionate impacts on socially vulnerable communities, on individuals who do not live or work in climate-controlled conditions (i.e., farm and outdoor workers), who rely on public or multi-modal means of transportation like walking or biking or have pre-existing medical conditions or disabilities.
Extreme heat can exacerbate droughts and impact the agricultural industry as well as adversely impact transportation infrastructure, such as causing the softening and expansion of asphalt surfaces, resulting in buckling, potholed and rutted roads. Impacts on roadways and rail lines can lead to closures and travel delays in the short term and accelerate the breaking down of infrastructure in the long term.
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Flooding
Localized flooding has the potential to significantly impact people, property, and critical infrastructure in the County. Undersized and aging drainage infrastructure, deferred maintenance, increased run-off due to drought conditions, the built environment and trends in precipitation and weather can all increase the risk of localized stormwater flooding. Climate change will likely exacerbate the intensity and magnitude of precipitation events, increasing the risk associated with localized stormwater flooding and causing drainage infrastructure to be undersized in increasingly more common events.
Additionally, unhoused residents living in stormwater drainage areas can increase flood risk due to accumulated debris and trash, complicating flood response and mitigation activities.
Additional problem statements, based on concerns from Jurisdictions and the HMP Steering Committee discussions:
Earthquake
Yolo County has several fault systems. Due to the location of population centers and building history in the County, any large earthquake will likely impact people, property, and critical infrastructure, including water systems, telecommunications infrastructure, roads, bridges, healthcare systems, and utilities. Damage and debris could isolate large populations from these critical lifelines. Older unreinforced-masonry structures in the County are particularly vulnerable to earthquake risk. An earthquake can also produce cascading impacts due to urban conflagration, wildfires, seiches, landslides, dam, and levee failure.
Utility Interruption/ PSPS
Heat-related equipment failures and electrical infrastructure igniting wildfires have resulted in unintentional and intentional rolling blackouts and power shutoffs throughout the County. Public Safety/ Utility Initiated Power Shut Offs to prevent wildfire ignition can have notably significant impacts due to the length of disruption time, limited efficacy of the strategy, and the effect on first responder capabilities. Extreme and prolonged heat waves across the state increase the demand for the aging electrical grid, significantly depleting electricity reserves and resulting in blackouts. Heatwaves are expected to increase in intensity and magnitude due to climate change, likely exacerbating this problem. Traditional energy sources increase climate change risk and fail more consistently, but alternative energy technology cannot meet current nighttime demand.
Additionally, Yolo County has limited microgrids, and reliance on the macrogrid makes the County vulnerable to rolling and prolonged power outages. Over the last decade, Yolo County 458
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residents have begun adjusting to the increasing unreliability of macro utilities. Loss of power for more than a few hours can result in large economic losses, specifically related to food and agriculture. More vulnerable populations in isolated areas or who rely on medical devices are at increased risk during prolonged power outages.
Severe Winter Storms
Severe winter storms have been increasing in intensity, magnitude, and severity in Yolo County and are associated with various hazards in this Plan. Severe winter storms and heavy rain can have significant impacts, including flash flooding, localized stormwater flooding, mudslides, and landslides. Secondary hazards can cause immobility and loss of utilities. Roads may become impassable due to flooding, downed trees, or landslides. Power lines may be down due to high winds, and services such as water or telecommunications infrastructure may be unable to operate without power.
Stormwater runoff from heavy rains can also impair water quality by washing pollutants into water bodies. Severe winter storms can also cause large storm surges and wave action along the coastline, flooding low-lying areas and causing dramatic erosion. Coastal bluff and cliff failure due to erosion can create hazardous conditions due to roadway collapse, undermined home foundations, and damage to utilities. Additionally, future sea level rise scenarios will likely exacerbate coastal and inland flood risks during winter storms.
Road Infrastructure
The occurrence of any hazard profiled in this Plan, in combination with aging and limited road infrastructure, can result in limited egress of evacuees and minimal ingress of first responders.
Roadways can be compromised in severe weather incidents, flooding events, further limiting road capacity. Road infrastructure needs to develop at a rate commensurate with the rate at the population, and housing is expanding. Further, the topography of the County limits where new roads can be built.
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Section 4.0: Capability Assessment Yolo Operational Area SECTION 4.0 CAPABILITY ASSESSMENT
The planning process identifies the hazards posing a threat to Yolo County Operational area and described, in general, the vulnerability of the Operational area to these risks. The next step is to assess what loss prevention mechanisms are in place, through the hazard mitigation Capability Assessment. The Capability Assessment helps determine the ability of a jurisdiction to implement a comprehensive mitigation strategy, and to identify potential opportunities for establishing or enhancing specific mitigation policies, programs, or projects. As in any planning process, it is important to establish the feasible goals and actions, based on an understanding of the organizational capacity of the agencies or departments tasked with their implementation.
The Capability Assessment is a tool used in determining which mitigation actions are practical and likely to be implemented over time based on local government’s existing authorities, policies, programs, and resources available to support such implementation. The combination of the hazard risk assessment with the capability assessment results in the Operational-area’s vulnerability to disasters, and more accurately focuses the goals, objectives, and proposed actions of this plan. The capability assessment has three parts:
1. Analysis of federal and state laws, ordinances, plans, and programs that can support or impact hazard mitigation actions.
2. An inventory of jurisdictional plans, ordinances, programs, technical studies, or activities already in place and their relevancy to hazard mitigation.
3. An analysis of a jurisdiction’s current capacity and resources to carry out relevant plans, ordinances, programs, and activities related to hazard mitigation.
The capability assessment helps to detect existing gaps, shortfalls, or weaknesses that could hinder proposed mitigation activities or exacerbate hazard vulnerability. The Capability Assessment also highlights any mitigation measures already in place or being implemented at the local government level, which should be leveraged, and continue to be supported and enhanced, through applicable future mitigation efforts.
The capability assessment serves as a critical part of the planning process and helps identify and target meaningful mitigation actions for incorporation into the Mitigation strategy. It helps establish the operational-area and jurisdiction-specific mitigation goals and ensures that the goals and mitigation actions that follow are realistically achievable given current local conditions.
4.1 INCORPORATION OF EXISTING PLANS, STUDIES, REPORTS, AND TECHNICAL
INFORMATION
Existing laws, ordinances, plans and programs at the federal, state, and local level can support or impact hazard mitigation actions identified in this plan. Hazard mitigation plans are required to include a review and incorporation, if appropriate, of existing plans, studies, reports, and 460
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Section 4.0: Capability Assessment Yolo Operational Area technical information as part of the planning process (44 CFR, Section 201.6(b)(3)). The following federal and state programs have been identified as programs that may interface with the actions identified in this plan. Each program enhances capabilities to implement mitigation actions or has a nexus with a mitigation action in this plan. Information presented in this section can be used in review local capabilities to implement the actions found in the jurisdictional annexes.
Each planning partner individually reviews existing local plans, studies, reports, and technical information in its jurisdictional annex.
4.1.1 FEDERAL
Disaster Mitigation Act (DMA)
The DMA is the current federal legislation addressing hazard mitigation planning. It emphasizes planning for disasters before they occur. It specifically addresses planning at the local level, requiring plans to be in place before Hazard Mitigation Assistance grant funds are available to communities. This plan is designed to meet the requirements of DMA, improving eligibility for future hazard mitigation funds.
National Incident Management System
The National Incident Management System (NIMS) is a systematic approach for government, nongovernmental organizations, and the private sector to work together to manage incidents involving hazards. The NIMS provides a flexible but standardized set of incident management practices. Incidents typically begin and end locally, and they are managed at the lowest possible geographical, organizational, and jurisdictional level. In some cases, success depends on the involvement of multiple jurisdictions, levels of government, functional agencies, and emergency responder disciplines. These cases necessitate coordination across a spectrum of organizations.
Communities using NIMS follow a comprehensive national approach that improves the effectiveness of emergency management and response personnel across the full spectrum of potential hazards (including natural hazards, terrorist activities, and other human-caused disasters) regardless of size or complexity. Although participation is voluntary, Federal departments and agencies are required to make adoption of NIMS by local and state jurisdictions a condition to receive Federal Preparedness grants and awards.
Community Development Block Grant Disaster Resilience Program In response to disasters, Congress may appropriate additional funding for the US Department of Housing and Urban Development Community Development Block Grant programs to be distributed as Disaster Recovery grants (CDBG-DR). These grants can be used to rebuild affected areas and provide seed money to start the recovery process. CDBG-DR assistance may fund a broad range of recovery activities, helping communities that otherwise might not recover due to limited resources. CDBG-DR grants often supplement disaster programs of the Federal 461
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Housing and Urban Development generally awards noncompetitive, nonrecurring CDBG-DR grants by a formula that considers disaster recovery needs unmet by other disaster assistance programs. CDGB-DR funding is a potential alternative source of funding for actions identified in this plan.
To be eligible for CDBG-DR funds, projects must meet the following criteria:
• Address a disaster-related impact (direct or indirect) in a presidentially declared county for the covered disaster.
• Be a CDBG-eligible activity (according to regulations and waivers) • Meet a national objective. Incorporating preparedness and mitigation into these actions is encouraged, as the goal is to rebuild in ways that are safer and stronger.
Emergency Watershed Program
The USDA Natural Resources Conservation Service (NRCS) administers the Emergency Watershed Protection (EWP) Program, which responds to emergencies created by natural disasters. Eligibility for assistance is not dependent on a national emergency declaration. The program is designed to help people and conserve natural resources by relieving imminent hazards to life and property caused by floods, fires, windstorms, and other natural occurrences.
EWP is an emergency recovery program. This federal program could be a possible funding source for actions identified in this plan. Financial and technical assistance are available for the following activities:
• Removing debris from stream channels, road culverts, and bridges • Reshaping and protect eroded banks.
• Correcting damaged drainage facilities
• Establishing cover on critically eroding lands
• Repairing levees and structures
• Repairing conservation practices
Emergency Relief for Federally Owned Roads Program
The US Forest Service’s Emergency Relief for Federally Owned Roads Program was established to assist federal agencies with repair or reconstruction of tribal transportation facilities, federal lands transportation facilities, and other federally owned roads that are open to public travel and have suffered serious damage by a natural disaster over a wide area or by a catastrophic failure.
The program funds both emergency and permanent repairs. Eligible activities under this program meet some of the goals and objectives for this plan and the program is a possible funding source for actions identified in this plan.
National Flood Insurance Program
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Section 4.0: Capability Assessment Yolo Operational Area The National Flood Insurance Program (NFIP) provides federally backed flood insurance in exchange for communities enacting floodplain regulations. Participation and good standing under NFIP are prerequisites to grant funding eligibility under the Robert T. Stafford Act.
Monterey County and all the municipal planning partners participate in the NFIP and have adopted regulations that meet the NFIP requirements. At the time of the preparation of this plan, all participating jurisdictions were in good standing with NFIP requirements. Full compliance and good standing under the NFIP are application prerequisites for all FEMA grant programs for which participating jurisdictions are eligible under this plan.
Presidential Executive Orders 11988 and 13690
Executive Order 11988 requires federal agencies to avoid to the extent possible the long and short-term adverse impacts associated with the occupancy and modification of floodplains and to avoid direct and indirect support of floodplain development wherever there is a practicable alternative. It requires federal agencies to provide leadership and take action to reduce the risk of flood loss, minimize the impact of floods on human safety, health, and welfare, and restore and preserve the natural and beneficial values of floodplains. The requirements apply to the following activities:
• Acquiring, managing, and disposing of federal lands and facilities • Providing federally undertaken, financed, or assisted construction and improvements. • Conducting federal activities and programs affecting land use, including but not limited to water and related land resources planning, regulation, and licensing.
Executive Order 13690 expands Executive Order 11988 and acknowledges that the impacts of flooding are anticipated to increase over time because of climate change and other threats. It mandates a federal flood risk management standard to increase resilience against flooding and help preserve the natural values of floodplains. This standard expands management of flood issues from the current base flood level to a higher vertical elevation and corresponding horizontal floodplain. The goal is to address current and future flood risk and ensure that projects funded with taxpayer dollars last as long as intended. All actions identified in this plan will seek full compliance with all applicable presidential executive orders.
The Clean Water Act
The federal Clean Water Act (CWA) employs regulatory and non-regulatory tools to reduce direct pollutant discharges into waterways, finance municipal wastewater treatment facilities, and manage polluted runoff. These tools are employed to achieve the broader goal of restoring and maintaining the chemical, physical, and biological integrity of the nation’s surface waters so that they can support “the protection and propagation of fish, shellfish, and wildlife and recreation in and on the water.”
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Section 4.0: Capability Assessment Yolo Operational Area Evolution of CWA programs over the last decade has included a shift from a program by program, source-by-source, and pollutant-by-pollutant approach to more holistic watershedbased strategies. Under the watershed approach, equal emphasis is placed on protecting healthy waters and restoring impaired ones. A full array of issues is addressed, not just those subject to CWA regulatory authority. Involvement of stakeholder groups in the development and implementation of strategies for achieving and maintaining water quality and other environmental goals is a hallmark of this approach.
The CWA is important to hazard mitigation in several ways. There are often permitting requirements for any construction within 200 feet of water of the United States, which may have implications for mitigation projects identified by a local jurisdiction. Additionally, CWA requirements apply to wetlands, which serve important functions related to preserving and protecting the natural and beneficial functions of floodplains and are linked with a community’s floodplain management program.
Finally, the National Pollutant Discharge Elimination System is part of the CWA and addresses local stormwater management programs. Stormwater management plays a critical role in hazard mitigation by addressing urban drainage or localized flooding issues within jurisdictions. FEMA hazard mitigation project grant applications require full compliance with applicable federal acts.
Any action identified in this plan that falls within the scope of this act will need to meet its requirements.
Presidential Executive Order 11990
Executive Order 11990 requires federal agencies to provide leadership and take action to minimize the destruction, loss, or degradation of wetlands, and to preserve and enhance the natural and beneficial values of wetlands. The requirements apply to the following activities:
• Acquiring, managing, and disposing of federal lands and facilities • Providing federally undertaken, financed, or assisted construction and improvements • Conducting federal activities and programs affecting land use, including but not limited to water and related land resources planning, regulation, and licensing. All actions identified in this plan will seek full compliance with all applicable presidential executive orders.
Endangered Species Act
The federal Endangered Species Act (ESA) was enacted in 1973 to conserve species facing depletion or extinction and the ecosystems that support them. The act sets forth a process for determining which species are threatened and endangered and requires the conservation of the critical habitat in which those species live. The ESA provides broad protection for species of fish, wildlife and plants that are listed as threatened or endangered. 464
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Section 4.0: Capability Assessment Yolo Operational Area Provisions are made for listing species, as well as for recovery plans and the designation of critical habitat for listed species. The ESA outlines procedures for federal agencies to follow when taking actions that may jeopardize listed species and contains exceptions and exemptions.
It is the enabling legislation for the Convention on International Trade in Endangered Species of Wild Fauna and Flora. Criminal and civil penalties are provided for violations of the ESA and the Convention. Federal agencies must seek to conserve endangered and threatened species and use their authorities in furtherance of the ESA’s purposes.
The ESA defines three fundamental terms:
• Endangered means that a species of fish, animal or plant is “in danger of extinction throughout all or a significant portion of its range.” (For salmon and other vertebrate species, this may include subspecies and distinct population segments.) • Threatened means that a species “is likely to become endangered within the foreseeable future.” Regulations may be less restrictive for threatened species than for endangered species.
• Critical habitat means “specific geographic areas that are essential for the conservation and management of a listed species, whether occupied by the species or not.” FEMA hazard mitigation project grant applications require full compliance with applicable federal acts. Any action identified in this plan that falls within the scope of this act will need to meet its requirements.
National Environmental Policy Act
The National Environmental Policy Act (NEPA) requires federal agencies to consider the environmental impacts of proposed actions and reasonable alternatives to those actions, alongside technical and economic considerations. NEPA established the Council on Environmental Quality (CEQ), whose regulations (40 CFR Parts 1500-1508) set standards for NEPA compliance. Consideration and decision-making regarding environmental impacts must be documented in an environmental impact statement or environmental assessment.
Environmental impact assessment requires the evaluation of reasonable alternatives to a proposed action, solicitation of input from organizations and individuals that could be affected, and an unbiased presentation of direct, indirect, and cumulative environmental impacts. FEMA hazard mitigation project grant applications require full compliance with applicable federal acts.
Any action identified in this plan that falls within the scope of this act will need to meet its requirements.
Americans with Disabilities Act
The Americans with Disabilities Act (ADA) seeks to prevent discrimination against people with disabilities in employment, transportation, public accommodation, communications, and government activities. Title II of the ADA deals with compliance with the Act in emergency 465
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Section 4.0: Capability Assessment Yolo Operational Area management and disaster-related programs, services, and activities. It applies to state and local governments as well as third parties, including religious entities and private nonprofit organizations.
The ADA has implications for sheltering requirements and public notifications. During an emergency alert, officials must use a combination of warning methods to ensure that all residents have all necessary information. Those with hearing impairments may not hear radio, television, sirens, or other audible alerts, while those with visual impairments may not see flashing lights or other visual alerts. Two technical documents for shelter operators address physical accessibility needs of people with disabilities, as well as medical needs and service animals. The ADA intersects with disaster preparedness programs in regard to transportation, social services, temporary housing, and rebuilding. Persons with disabilities may require additional assistance in evacuation and transit (e.g., vehicles with wheelchair lifts or paratransit buses).
Evacuation and other response plans should address the unique needs of residents. Local governments may be interested in implementing a special-needs registry to identify the home addresses, contact information, and needs for residents who may require more assistance. FEMA hazard mitigation project grant applications require full compliance with applicable federal acts.
Any action identified in this plan that falls within the scope of this act will need to meet its requirements.
Civil Rights Act of 1964
The Civil Rights Act of 1964 prohibits discrimination based on race, color, religion, sex, or nation origin and requires equal access to public places and employment. The Act is relevant to emergency management and hazard mitigation in that it prohibits local governments from favoring the needs of one population group over another. Local government and emergency response must ensure the continued safety and well-being of all residents equally, to the extent possible. FEMA hazard mitigation project grant applications require full compliance with applicable federal acts. Any action identified in this plan that falls within the scope of this act will need to meet its requirements.
Army Corps of Engineers Programs
The US Army Corps of Engineers has several civil works authorities and programs related to flood risk and flood hazard management. The Floodplain Management Services program offers 100-% federally funded technical services such as development and interpretation of site-specific data related to the extent, duration, and frequency of flooding. Special studies may be conducted to help a community understand and respond to flood risk. These may include flood hazard evaluation, flood warning and preparedness, or flood modeling.
For more extensive studies, the Army Corps offers a cost-shared program called Planning Assistance to States and Tribes. Studies under this program generally range from $25,000 to 466
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Section 4.0: Capability Assessment Yolo Operational Area $100,000 with the local jurisdiction providing 50% of the cost. The Army Corps has several cost shared programs (typically 65% federal and 35% non-federal) aimed at developing, evaluating, and implementing structural and non-structural capital projects to address flood risks at specific locations or within a specific watershed, including:
• The Continuing Authorities Program for smaller-scale projects includes Section 205 for Flood Control, with a $7 million federal limit and Section 14 for Emergency Streambank Protection with a $1.5 million federal limit. These can be implemented without specific authorization from Congress.
• Larger scale studies, referred to as General Investigations, and projects for flood risk management, for ecosystem restoration or to address other water resource issues, can be pursued through a specific authorization from Congress and are cost-shared, typically at 65% federal and 35% nonfederal.
• Watershed management planning studies can be specifically authorized and are costshared at 50% federal and 50% non-federal.
The Army Corps also provides emergency response assistance during and following natural disasters. Public Law 84-99 enables the Corps to assist state and local authorities in flood fight activities and cost share in the repair of flood protective structures. The Flood Control and Coastal Emergency Act establishes an emergency fund for preparedness for emergency response to natural disasters; for flood fighting and rescue operations; for rehabilitation of flood control and hurricane protection structures. Funding for the Army Corps emergency response under this authority is provided by Congress through the annual Energy and Water Development Appropriation Act. Disaster preparedness activities include coordination, planning, training and conduct of response exercises with local, state, and federal agencies.
Under PL 84-99, the Army Corps can supplement state and local entities in flood fighting urban and other non-agricultural areas under certain conditions (Engineering Regulation 500-1-1 provides specific details). All flood fight efforts require a project cooperation agreement signed by the public sponsor and the sponsor must remove all flood fight material after the flood has receded. PL 84-99 also authorizes emergency water support and drought assistance in certain situations and allows for “advance measures” assistance to prevent or reduce flood damage conditions of imminent threat of unusual flooding.
Under PL 84-99, an eligible flood protection system can be rehabilitated if damaged by a flood event. The flood system would be restored to its pre-disaster status at no cost to the federal system owner, and at 20% cost to the eligible non-federal system owner. All systems considered eligible for PL 84-99 rehabilitation assistance have to be in the Rehabilitation and Inspection Program prior to the flood event. Acceptable operation and maintenance by the public levee sponsor are verified by levee inspections conducted by the Corps on a regular basis. The Corps has the responsibility to coordinate levee repair issues with interested federal, state, and local 467
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Section 4.0: Capability Assessment Yolo Operational Area agencies following natural disaster events where flood control works are damaged. All of these authorities and programs are available to the planning partners to support any intersecting mitigation actions.
4.1.2 STATE
Alquist-Priolo Earthquake Fault Zoning Act
The Alquist-Priolo Earthquake Fault Zoning Act was enacted in 1972 to mitigate the hazard of surface faulting to structures for human occupancy. The Alquist-Priolo Earthquake Fault Zoning Acts main purpose is to prevent construction of buildings used for human occupancy on the surface trace of active faults. Before a new project is permitted, cities and counties require a geologic investigation to demonstrate that proposed buildings will not be constructed on active faults. The act addresses only the hazard of surface fault rupture and is not directed toward other earthquake hazards, such as liquefaction or seismically induced landslides.
The law requires the State of California Geologist to establish regulatory zones around the surface traces of active faults and to issue appropriate maps. The maps are distributed to all affected cities, counties, and state agencies for their use in planning and controlling new or renewed construction. Local agencies must regulate most development projects within the zones.
Projects include all land divisions and most structures for human occupancy. All seismic hazard mitigation actions identified in this plan will seek full compliance with the Alquist-Priolo Earthquake Fault Zoning Act.
California General Planning Law
California state law requires that every county and city prepare and adopt a comprehensive longrange plan to serve as a guide for community development. The general plan expresses the community’s goals, visions, and policies relative to future land uses, both public and private. The general plan is mandated and prescribed by state law (Cal. Gov. Code §65300 et seq.) and forms the basis for most local government land use decision-making.
The plan must consist of an integrated and internally consistent set of goals, policies, and implementation measures. In addition, the plan must focus on issues of the greatest concern to the community and be written in a clear and concise manner. City and county actions, such as those relating to land use allocations, annexations, zoning, subdivision and design review, redevelopment, and capital improvements, must be consistent with the plan. All municipal planning partners to this plan have general plans that are currently compliant with this law and have committed to integrating this mitigation plan with their general plans through provisions referenced below (AB-2140 and SB-379).
California Environmental Quality Act
The California Environmental Quality Act (CEQA) was passed in 1970, shortly after the federal government enacted the National Environmental Policy Act, to institute a statewide policy of 468
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Section 4.0: Capability Assessment Yolo Operational Area environmental protection. CEQA requires state and local agencies in California to follow a protocol of analysis and public disclosure of the potential environmental impacts of development projects. CEQA makes environmental protection a mandatory part of every California state and local agency’s decision-making process.
CEQA establishes a statewide environmental policy, and mandates actions all state and local agencies must take to advance the policy. Jurisdictions conduct analysis of the project to determine if there are potentially significant environmental impacts, identify mitigation measures, and possible project alternatives by preparing environmental reports for projects that requires CEQA review. This environmental review is required before an agency acts on any policy, program, or project.
Yolo County has determined that this plan update is categorically exempt from the formal CEQA protocol. The County will initiate the formal CEQA protocol on any project recommended in this plan that requires adherence to this protocol at the initiation of the project. Any project action identified in this plan will seek full CEQA compliance upon implementation.
California Disaster Assistance Act
The California Disaster Assistance Act (CDAA) authorizes the Director of the California Governor’s Office of Emergency Services (Cal OES) to administer a disaster assistance program that provides financial assistance from the state for costs incurred by local governments because of a disaster event. Funding for the repair, restoration, or replacement of public real property damaged or destroyed by a disaster is made available when the Director concurs with a local emergency proclamation requesting state disaster assistance.
The program also provides for the reimbursement of local government costs associated with certain emergency activities undertaken in response to a state of emergency proclaimed by the Governor. In addition, the program may provide matching fund assistance for cost sharing required under federal public assistance programs in response to a Presidential Major Disaster or Emergency Declaration. The implementing regulations for CDAA can be found in Title 19 of the California Code of Regulations, Chapter 6.
Assembly Bill 162: Flood Planning
This California State Assembly Bill passed in 2007 requires cities and counties to address floodrelated matters in the land use, conservation, and safety and housing elements of their general plans. The land use element must identify and annually review the areas covered by the general plan that are subject to flooding as identified in floodplain mapping by either FEMA or the state Department of Water Resources (DWR). During the next revision of the housing element on or after January 1, 2009, the conservation element of the general plan must identify rivers, creeks, 469
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Section 4.0: Capability Assessment Yolo Operational Area streams, flood corridors, riparian habitat, and land that may accommodate floodwater for the purpose of groundwater recharge and stormwater management.
The safety element must identify information regarding flood hazards, including:
• Flood hazard zones.
• Maps published by FEMA, DWR, the US Army Corps of Engineers, the Central Valley Flood Protection Board, and the Governor’s Office of Emergency Services (Cal OES) • Historical data on flooding
• Existing and planned development in flood hazard zones The general plan must establish goals, policies, and objectives to protect from unreasonable flooding risks, including:
• Avoiding or minimizing the risks of flooding new development • Evaluating whether new developments should be in flood hazard zones. • Identifying construction methods to minimize damage.
AB 162 establishes goals, policies, and objectives to protect from unreasonable flooding risks. It establishes procedures for the determination of available land suitable for urban development, which may exclude lands where FEMA or DWR has concluded that the flood management infrastructure is not adequate to avoid the risk of flooding.
Assembly Bill 2140: General Plans—Safety Element
This bill provides that the state may allow for more than 75% of public assistance funding under the California Disaster Assistance Act only if the local agency is in a jurisdiction that has adopted a local hazard mitigation plan as part of the safety element of its general plan. The local hazard mitigation plan needs to include elements specified in this legislation. In addition, this bill requires Cal OES to give preference for federal mitigation funding to cities and counties that have adopted local hazard mitigation plans. The intent of the bill is to encourage cities and counties to create and adopt hazard mitigation plans.
Assembly Bill 70: Flood Liability
This bill provides that a city or county may be required to contribute a fair and reasonable share to compensate for property damage caused by a flood to the extent that it has increased the state’s exposure to liability for property damage by unreasonably approving new development in a previously undeveloped area that is protected by a state flood control project, unless the city or county meets specified requirements.
Assembly Bill 32: The California Global Warming Solutions Act This bill identifies the following potential adverse impacts of global warming:
• Exacerbation of air quality problems
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Section 4.0: Capability Assessment Yolo Operational Area • Reduction in the quality and supply of water to the state from the Sierra snowpack • A rise in sea levels resulting in the displacement of thousands of coastal businesses and residences, damage to marine ecosystems and the natural environment. • An increase in the incidences of infectious diseases, asthma, and other human healthrelated problems AB 32 establishes a state goal of reducing greenhouse gas emissions to 1990 levels by 2020 (a reduction of approximately 25% from forecast emission levels), with further reductions to follow. The law requires the state Air Resources Board to establish a program to track and report greenhouse gas emissions, approve a scoping plan for achieving the maximum technologically feasible and cost-effective reductions from sources of greenhouse gas emissions, adopt early reduction measures to begin moving forward, and adopt, implement, and enforce regulations, including market mechanisms such as “cap and-trade” programs, to ensure that the required reductions occur. The Air Resources Board has adopted a statewide greenhouse gas emissions limit and an emissions inventory, along with requirements to measure, track, and report greenhouse gas emissions by the industries it determined to be significant sources of greenhouse gas emissions.
Senate Bill 97: Guidelines for Greenhouse Gas Emissions Senate Bill 97, enacted in 2007, amends CEQA to clearly establish that greenhouse gas emissions and the effects of greenhouse gas emissions are appropriate subjects for CEQA analysis. It directs the Governor’s Office of Planning and Research to develop draft CEQA guidelines for the mitigation of greenhouse gas emissions or their effects by July 2009 and directs the California Natural Resources Agency to certify and adopt the CEQA Guidelines by January 1, 2010.
Senate Bill 1241: General Plans: Safety Element—Fire Hazard Impacts In 2012, Senate Bill 1241 was enacted, requiring that all future General Plans address fire risk in state responsibility areas and very high fire hazard severity zones in their safety element. In addition, the bill requires cities and counties to make certain findings regarding available fire protection and suppression services before approving a tentative map or parcel map.
Senate Bill 1000: General Plan Amendments—Safety and Environmental Justice Elements In 2016, Senate Bill 1000 amended California’s Planning and Zoning Law in two ways. The original law established requirements for initial revisions of general plan safety elements to address flooding, fire, and climate adaptation and resilience. It also required subsequent review and revision as necessary based on new information. Senate Bill 1000 specifies that the subsequent reviews and revision based on new information are required to address only flooding and fires (not climate adaptation and resilience).
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Section 4.0: Capability Assessment Yolo Operational Area Additionally, Senate Bill 1000 adds a requirement that, upon adoption or revision of any two other general plan elements on or after January 1, 2018, an environmental justice element be adopted for the general plan or environmental justice goals, policies and objectives be incorporated into other elements of the plan.
Senate Bill 379: General Plans: Safety Element—Climate Adaptation Senate Bill 379 builds upon the flood planning inclusions into the safety and housing elements and the hazard mitigation planning safety element inclusions in general plans outlined in AB 162 and AB 2140, respectively. SB 379 focuses on a new requirement that cities and counties include climate adaptation and resiliency strategies in the safety element of their general plans beginning January 1, 2017. In addition, this bill requires general plans to include a set of goals, policies and objectives, and specified implementation measures based on the conclusions drawn from climate adaptation research and recommendations.
This update process for this hazard mitigation plan was conducted with the intention of full compliance with this bill. However, at the time of the update, there was no clear guidance from the state on what constitutes full compliance or what protocol is to be used to determine compliance. When such guidance has been established, the planning partners will submit this plan or its subsequent updates to the state for review and approval.
California State Building Code California Code of Regulations Title 24 (CCR Title 24), also known as the California Building Standards Code, is a compilation of building standards from three sources:
• Building standards that have been adopted by state agencies without change from building standards contained in national model codes.
• Building standards that have been adopted and adapted from the national model code standards to meet California conditions.
• Building standards authorized by the California legislature that constitute extensive additions not covered by the model codes adopted to address California concerns.
The state Building Standards Commission is authorized by California Building Standards Law (Health and Safety Code Sections 18901 through 18949.6) to administer the processes related to the adoption, approval, publication, and implementation of California’s building codes. These building codes serve as the basis for the design and construction of buildings in California. The national model code standards adopted into Title 24 apply to all occupancies in California, except for modifications adopted by state agencies and local governing bodies. Since 1989, the Building Standards Commission has published new editions of Title 24 every three years.
Standardized Emergency Management System
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Section 4.0: Capability Assessment Yolo Operational Area CCR Title 19 establishes the Standardized Emergency Management System (SEMS) to standardize the response to emergencies involving multiple jurisdictions. SEMS is intended to be flexible and adaptable to the needs of all emergency responders in California. It requires emergency response agencies to use basic principles and components of emergency management. Local governments must use SEMS by December 1, 1996, to be eligible for state funding of response-related personnel costs under CCR Title 19 (Sections 2920, 2925 and 2930).
The roles and responsibilities of Individual agencies contained in existing laws, or the state emergency plan are not superseded by these regulations. This hazard mitigation plan is a support document for all phases of emergency management, including those associated with SEMS.
State of California State Hazard Mitigation Plan (SHMP) Under the DMA, California must adopt a federally approved state multi-hazard mitigation plan to be eligible for certain disaster assistance and mitigation funding. The intent of the State of California Hazard Mitigation Plan is to reduce or prevent injury and damage from hazards in the state through the following:
• Documenting statewide hazard mitigation planning in California • Describing strategies and priorities for future mitigation activities • Facilitating the integration of local and tribal hazard mitigation planning activities into statewide efforts
• Meeting state and federal statutory and regulatory requirements The plan is an annex to the State Emergency Plan, and it identifies past and present mitigation activities, current policies and programs, and mitigation strategies for the future. It also establishes hazard mitigation goals and objectives. The plan will be reviewed and updated annually to reflect changing conditions and new information, especially information on local planning activities. Under 44 CFR Section 201.6, local hazard mitigation plans must be consistent with their state’s hazard mitigation plan. In updating this plan, the Steering Committee reviewed the California State Hazard Mitigation Plan to identify key relevant state plan elements.
California Adaptation Planning Guide
The California Adaptation Planning Guide (APG), updated in 2020, is designed to support local government, regional organizations, and climate collaborative groups to integrate best practices and current science into their adaptation planning efforts. The APG provides helpful resources to local governments as they comply with state requirements for local adaptation planning and provides recommendations and advice on community-level climate change adaptation planning.
Safeguarding California Plan
The Safeguarding California Plan– California’s Climate Adaptation Strategy was updated in 2018. The update is the State’s roadmap for the strategies that will be used by state agencies to protect communities, infrastructure, services, and the natural environment from climate change 473
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Section 4.0: Capability Assessment Yolo Operational Area impacts. This holistic strategy primarily covers state agencies’ programmatic and policy responses across different policy areas, but it also discusses the ongoing related work to with coordinated local and regional adaptation action and developments in climate impact science.
Governor’s Executive Order S-13-08
Governor’s Executive Order S-13-08 enhances the state’s management of climate impacts from sea level rise, increased temperatures, shifting precipitation and extreme weather events. There are four key actions in the executive order:
• Initiate California’s first statewide climate change adaptation strategy to assess expected climate change impacts, identify where California is most vulnerable, and recommend adaptation policies. This effort will improve coordination within state government so that better planning can more effectively address climate impacts on human health, the environment, the state’s water supply and the economy.
• Request that the National Academy of Science establish an expert panel to report on sea level rise impacts in California, to inform state planning and development efforts. • Issue interim guidance to state agencies for how to plan for sea level rise in designated coastal and floodplain areas for new projects.
• Initiate a report on critical infrastructure projects vulnerable to sea level rise.
Senate Bill 99 General Plans: Safety Element: Emergency Evacuation Routes SB 99 requires that, upon the next revision of the housing element on or after January 1, 2020, local governments to review and update the safety element of their General Plan to include information identifying residential developments in hazard areas that do not have at least 2 emergency evacuation routes.
Assembly Bill 747 Planning and Zoning: General Plan: Safety Element AB 747 requires, that upon the next revision of a local hazard mitigation plan on or after January 1, 2022, the safety element to be reviewed and updated as necessary to identify evacuation routes and their capacity, safety, and viability under a range of emergency scenarios. The bill authorizes a city or county that has adopted a local hazard mitigation plan, emergency operations plan, or other document that fulfills commensurate goals and objectives to use that information in the safety element to comply with this requirement by summarizing and incorporating by reference that other plan or document in the safety element.
Strategic Fire Plan for California
The Strategic Fire Plan for California is the state's road map for reducing the risk of wildfire. The Fire Plan is a cooperative effort between the State Board of Forestry and Fire Protection and the California Department of Forestry and Fire Protection. The 2018 update reflects a focus on (1) fire prevention and suppression activities to protect lives, property, and ecosystem services, and (2) natural resource management to maintain the state’s forests as a resilient carbon sink to meet 474
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Section 4.0: Capability Assessment Yolo Operational Area California’s climate change goals and to serve as important habitat for adaptation and mitigation.
By placing the emphasis on what needs to be done long before a fire starts, the Strategic Fire Plan looks to reduce firefighting costs and property losses, increase firefighter safety, and contribute to overall ecosystem health.
Fire Hazard Planning: General Plan Technical Advice Series CA Governor's Office of Planning and Research (OPR) Fire Hazard Planning technical advisory provides guidance on those policies and programs and is also intended to assist city and county planners in discussions with professionals from fire hazard prevention and mitigation, disaster preparedness, and emergency response and recovery agencies as they work together to develop effective fire hazard policies for the general plan. The 2020 update includes specific land use strategies to reduce fire risk to buildings, infrastructure, and communities and was prepared in consultation with the Department of Forestry and Fire Protection, the State Board of Forestry and Fire Protection, and other fire and safety experts.
4.1.3 LOCAL CAPABILITY ASSESSMENT
PLANNING AND REGULATORY CAPABILITY
Hazard mitigation planning must include review and incorporation, if appropriate, of existing plans, studies, reports, and technical information (44 CFR, Section 201.6(b)(3)). Additionally, per 44 CFR Section 201.6(c)(3), the plan must include a mitigation strategy based on existing authorities, policies, programs, and resources, therefore each jurisdiction undertook a review of their current capabilities to implement hazard mitigation actions.
The Capability Assessment Survey requested information on a variety of “capability indicators” such as existing local plans, policies, programs, or ordinances that may reduce, or in some circumstances, increase the community’s hazard vulnerability. Other indicators included information related to each jurisdiction’s fiscal, administrative, and technical capabilities such as access to local budgetary and personnel resources necessary to implement hazard mitigation measures. Survey respondents were also asked to comment on existing activities or capabilities to conduct public education and outreach, as well as the current political climate in their jurisdiction to implement hazard mitigation actions. The Survey was based on the FEMA recommended tool and included a summary of a jurisdiction’s overall capability in the following four different types of capabilities as defined by FEMA. 91 91 Local Mitigation Planning Handbook, Worksheet 4.1: Capability Assessment Worksheet, FEMA (March 2013) • Planning and Regulatory Capabilities: capabilities based on the jurisdiction’s implementation of ordinances, policies, local laws, and State statutes, and plans and programs that relate to guiding and managing growth and development. • Administrative and Technical Capabilities: capabilities associated with the jurisdiction’s staff and their skills and tools that can be used for mitigation planning and to implement specific mitigation actions.
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Section 4.0: Capability Assessment Yolo Operational Area • Fiscal Capabilities: refers to the fiscal resources that a jurisdiction has access to or is eligible to use to fund mitigation actions.
• Education and Outreach Capabilities: refers to education and outreach programs and methods already in place that could be used to implement mitigation activities and communicate hazard-related information.
The analyzing these capabilities helps to accurately assess each jurisdiction’s degree of local capability, but also serves as a source of introspection for jurisdictions to assess their capability and recast identified gaps, weaknesses, or conflicts as opportunities to be addressed in the development of new mitigation actions. The documents and resources included and assessed under each capability category are summarized in the Table below.
Table 4-1: Documents and Resources in Yolo County Operational Area Assessed Planning and Regulatory Capability
Planning Documents
General Plan
Capital Improvement Plan
Floodplain Management Plan
Climate Action & Adaptation Plan
Emergency Operations Plan
Continuity of Operations Plan
Wildfire Protection Plan
Historic Preservation Plan
Disaster Recovery Plan
Economic Development Plan
Code, Ordinance, or Requirements
Zoning Ordinance
Building Code
Fire Prevention Code
Subdivision ordinance or regulations
Special Purpose Ordinances (Floodplain
Management, storm water management, hillside
or steep slope ordinances, wildfire ordinances,
hazard setback requirements)
Administrative and Technical Capability
Planner or engineer with knowledge of land
development and land management practices
Engineer or professional trained in construction
practices related to buildings and/or infrastructure
Planner or engineer with understanding of
manmade or natural hazards
Building inspector
Floodplain manager
Staff with education/expertise to assess
community’s vulnerability to hazards
Maintenance programs to reduce risk
Emergency Manager
Land Surveyors
Public Information Officer
Personnel skilled in Geographic Information
Systems (GIS)
Warning Systems/services
Mutual Aid Agreements
Fiscal Capabilities
Funds and Taxes
General Funds
Capital Improvement Project Funding
Fees
Bonds and Grants
Education & Outreach Capabilities
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Section 4.0: Capability Assessment Yolo Operational Area Local Citizen or non-profit groups focused on environmental protection, emergency preparedness, access and functional needs populations, etc.
On-going public education or information program (fire safety, preparedness, etc.) Natural disaster or safety related school programs
Public-private partnership initiatives addressing disaster-related issues Additionally, classifications under various community mitigation programs were included. Other programs, such as the Community Rating System, Storm Ready, and Firewise USA, can enhance a jurisdiction’s ability to mitigate, prepare for, and respond to natural hazards. These programs indicate a jurisdiction’s desire to go beyond minimum requirements set forth by local, state, and federal regulations to create a more resilient community. These programs complement each other by focusing on communication, mitigation, and community preparedness to save lives and minimize the impact of natural hazards on a community.
4.2 EXPANDING CAPABILITIES
After assessing the various documents and resources listed in Table 4-1, we identified potential gaps in core capabilities. Filling these gaps may eventually become mitigation actions in the plan. These findings were shared with the Jurisdictions as they assessed their own capabilities, and developed mitigation actions. When an opportunity was identified to add or expand an existing capability, it was then identified as a potential mitigation action to consider. Each Jurisdiction must consider their own capabilities and how they can expand upon these capabilities.
EXPANDING PLANNING AND REGULATORY CAPABILITIES
With the update of the 2023 Yolo County Multi-jurisdictional HMP, it provides an opportunity to re-examine the Health and Safety Element of the 2030 Yolo County General Plan. The 2023 HMP Update also aligns with an update of the Yolo County Emergency Operations Plan and City Emergency Operations Plans for those participating jurisdictions. Our Climate Action and Adaptation Plan update, with the goal of meeting a carbon-negative footprint by 2030, is also underway. There continues to be opportunities for the HMP and Climate Action and Adaptation plan to collaborate on mitigation actions to reduce hazards affected by climate change. Planning members of the Climate Action and Adaptation plan serve as Steering Committee members of the HMP and vice versa, allowing for opportunities to integrate various aspects of these plans.
The Office of Emergency Services continues to serve on a committee established through the Climate Action and Adaption Plan update which increases the department’s ability to anticipate impacts from future climate change conditions. This increases collaboration with engaging the public, increases administrative/technical capabilities through working with climate change subject matter expertise, and continues to incorporate climate action and adaptation measures into hazard mitigation.
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Section 4.0: Capability Assessment Yolo Operational Area
EXPANDING CODE, ORDINANCE, OR REQUIREMENTS CAPABILITIES Jurisdictions regulate land use through the adoption and enforcement of zoning, subdivision and land development ordinances, building codes, building permit ordinances, floodplain, and stormwater management ordinances. When effectively prepared and administered, these regulations can lead to hazard mitigation.
National Flood Insurance Program compliance was one area in which gaps were identified and opportunities for expanding the program. In Yolo County, the Department of Community Services, Building Services Division develops, and issues permits, is responsible for floodplain management, and NFIP Compliance. Assessment of Yolo County’s current NFIP status and compliance provided planners with a greater understanding of the local flood management program, opportunities for improvement and greater collaboration between the Office of Emergency Services planners and Yolo County Department of Community Services, Building Services Division and Chief Building Official. As Yolo County participates in the Community Rating System (CRS), there are opportunities to improving the CRS Classification. The Office of Emergency Services has discussed these opportunities to improve the CRS Classification as we just completed the FEMA Community Rating System Annual Recertification in 2023, there is an opportunity in 2024 during the cycle verification to request additional credits to improve our CRS Rating Classification.
EXPANDING ADMINISTRATIVE AND TECHNICAL CAPABILITIES
Given that the 2023 HMP Update was completed without grant funding, in the next 2028 Update, we are planning on applying for grant funding opportunities as we recognized the gap with engineers, surveyors, personnel skilled and trained in GIS applications, scientists familiar with natural hazards in Yolo County Operational area. In Yolo County these positions are often filled by the same person in multiple roles. Grant funding in the future could open opportunities to contract out some of these personnel resources and alleviate competing work priorities and needs.
EXPANDING FISCAL CAPABILITIES
Given that the 2023 HMP Update was completed without grant funds, there is an opportunity to actively seek out grant funding opportunities for the 2028 HMP Update. It was also identified in the capability assessment process that in the Office of Emergency Services, rather than having one grants administrator, to divide up grant management amongst the planners and coordinators to open more grant funding opportunities to jurisdictions. There are opportunities to seek funding for capital improvement projects, community development block grants, as well as statesponsored grant programs that previously we did not have the bandwidth to seek after.
EXPANDING EDUCATION AND OUTREACH CAPABILITIES
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Section 4.0: Capability Assessment Yolo Operational Area During the 2023 HMP Update process, we identified gaps in education and outreach around hazard mitigation. During the update process, we had a new Public Information Officer, who started revamping the Yolo County website and updating information. There continues to be opportunities to create public awareness around hazard mitigation not only through information provided on the website, but also through creating a more user-friendly website on hazard mitigation to create more public education and awareness around hazard mitigation.
We also identified through the HMP Steering Committee, a need to create workgroups for planning purposes for Access and Functional Needs and a Cultural Diversity workgroup. These workgroups will provide a forum for greater community engagement across geographically, socially, and physically diverse groups and engage with diverse communities within the County.
These working groups also will expand abilities to communicate hazard-related information and education. For example, one project these working groups will start with is looking at Access and Functional Needs Annex and looking at the Alert and Warning systems currently in place including a gap analysis, how the system can be improved and more inclusive for the Access and functional needs population.
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SECTION 5.0 MITIGATION STRATEGY
Hazard mitigation plans must identify goals for reducing long-term vulnerabilities to identified hazards (44 CFR Section 201.6(c)(3)(1)). The mitigation strategy section is a blueprint for Yolo County to follow to become less vulnerable to the negative effects of the hazards identified and addressed in this Plan. The mitigation strategy intends to provide Yolo County with a vision and overall goals that will serve as guiding principles for future mitigation policy and project administration, along with an analysis of mitigation techniques deemed available to meet those goals and reduce the impact of identified hazards.
The County of Yolo endeavors to be a disaster-resistant and resilient community that can survive and recover from a disaster while preserving the quality of life for residents and the diversity and quality of its natural and built environments. The community strives to offer excellent cultural and community services while maintaining and improving infrastructure, community safety, and emergency preparedness. This Local Hazard Mitigation Plan (LHMP) is a part of this effort.
The County of Yolo has developed a range of policies and programs to act as a “blueprint” for the Hazard Mitigation Strategy. Strategies include “everyday operations” that also contribute to reducing the impact of future hazards as well as specific hazard mitigation projects. While County efforts are focused on evaluating and improving County-owned structures, particularly those identified as critical facilities, the plan also encourages the establishment of standards to encourage private property owners to upgrade the hazard resistance of their properties. Finally, the County is actively engaged with other local and regional organizations to collaboratively work towards mitigation actions that meet the County of Yolo’s objective to be a healthy, safe, and more affordable community that is culturally diverse, economically inclusive, and environmentally vibrant.
This plan focuses on mitigation goals and actions, meaning activities executed prior to a hazard event that reduces or avoids damage when disasters strike. Damage prevention includes structural improvements to existing buildings, land use decisions that minimize damage, and ongoing programs such as fire vegetation management in wildland/urban interface areas.
Hazard mitigation plans must identify goals for reducing long-term vulnerabilities to identified hazards (44 CFR Section 201.6(c)(3)(i)). The Steering Committee estimated the impacts of the hazards based on the hazard analysis and vulnerabilities (see Hazard Profiles Section 3.0). They then established problem statements, describing the overall hazard issues and problems needing to be addressed (see Problem Statements Section 3.12). They assessed what resources currently exist to lessen impacts of hazards and the problems identified, and how exisiting capabilities could be expanded upon (see Capability Assessments Section 4.0). The Steering Committee then established a mission statement, a set of goals, and measurable objectives to address the 480
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problems (see Mitigation Mission Statement (Section 5.1), Goals (Section 5.3), and Objectives (Section 5.4)). The mission statement, goals, objectives and actions in this plan all support each other. Goals were selected to support the mission statement. Objectives were selected that meet multiple goals. Then Mitigation Actions were prioritized based on ability to accomplish multiple objectives.
5.1 MISSION STATEMENT
The Steering Committee developed the following new mission statement for this update:
To join with our community to maintain and enhance a disaster-resistant County by reducing the potential for loss of life, property, and environmental damage from natural and human-caused disasters, while supporting economic recovery from those disasters.
5.2 GUIDING PRINCIPLES
A guiding principle focuses on the range of objectives and actions to be considered. The purpose of the guiding principle is to represent the overall intended outcome of the Joint Hazard Mitigation Plan. The guiding principle for this hazard mitigation plan is as follows:
Reducing the risk of life and property to Yolo County efficiently and effectively by decreasing the long-term vulnerability from hazards through coordinated planning, partnerships, capacity building, and implementing effective risk reduction measures.
5.3 MITIGATION GOALS
Hazard mitigation plans must identify goals for reducing long-term vulnerabilities to identified hazards (44 C.F.R. 201.6(c)(3)(i)). Mitigation goals represent broad statements that are achieved through the implementation of more specific mitigation actions. Each goal, purposefully broad in nature, establishes parameters used to review and update existing mitigation actions and to aid in formulating new ones.
Goals are general guidelines that explain what is to be achieved. They are broad-based, policytype statements, which are long-term and represent global visions. Goals help define the benefits that the plan is trying to achieve. The success of the LHMP, once implemented, should be measured by the degree to which its goals have been met.
The County of Yolo LHMP team held several meetings to review the identified risks and developed goals, objectives, and actions based on the risk assessment. Goals that provided the greatest benefit in hazard reduction were identified as primary goals. Additional goals, specifically related to each identified potential hazard are presented under each hazard heading.
The goals form the basis for the development of Mitigation Action Strategy and specific mitigation projects. The effectiveness of a mitigation strategy is assessed by determining how 481
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well these goals are achieved. Continually implementing mitigation actions over time will ensure these mitigation goals are achieved.
Goals for this plan update include:
Goal 1: Protect life
1.1 Identify and protect vulnerable populations
1.2 Reduce public health risk from hazards
1.3 Improve and promote systems that provide early warning communications Goal 2: Protect property and infrastructure
2.1 Strengthen and enforce government codes to reduce vulnerability
2.2 Consider known hazards when identifying sites for new facilities, substantial retrofits, and utility systems.
2.3 Adopt and enforce public policies to promote resilient development and enhance safe construction in high hazard areas.
2.4 Integrate new hazard and risk information into building codes and land use planning mechanisms.
2.5 Encourage the development and incorporation of innovative technological solutions without compromising neighborhood or building character.
2.6 Incorporate effective mitigation strategies into governmental capital improvement projects.
2.7 Implement mitigation programs that promote reliability of lifeline systems to minimize impacts
from, and expedite recovery in, an emergency.
2.8 Improve/create redundancies for critical networks such as water, transportation, energy, sewer, digital, data and power, and communications.
2.9 Advocate for appropriate mitigation of all public and private property Goal 3: Foster an economy that promotes mitigation and recovery
3.1 Develop plans that restore critical business operations post disaster.
3.2 Form partnerships to leverage and share resources.
3.3 Educate businesses about contingency planning, targeting small businesses and those located in high-risk areas.
3.4 Encourage federal/state/local government partners to provide more funding opportunities for mitigation strategy investment.
Goal 4: Promote a healthy and equitable environment
4.1 Advance understanding about the relationship between climate change and natural hazards.
4.2 Improve knowledge of current and future climate-related hazards
4.3 Promote community-based mitigation strategies.
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4.4 Develop hazard mitigation and climate change adaptation policies that prevent long-term negative effects on the environment.
4.5 Encourage mitigation strategies in socially (e.g., age, poverty, race, disability) vulnerable populations and physically (floodplain) vulnerable neighborhoods.
Goal 5: Promote public awareness of hazard risk and mitigation
5.1 Support improved community engagement and outreach to vulnerable populations.
5.2 Improve access to hazard information, data, and maps.
5.3 Improve public knowledge of natural and non-natural hazards and protective measures.
5.4 Encourage creation of searchable databases and data visualizations using available evidence and scientific analysis on hazards, risks and vulnerabilities.
5.5 Partner with private sector to promote hazard mitigation as part of standard business practices.
5.6 Educate public officials, developers, realtors, contractors, building owners and the general public about hazard risks and building requirements.
5.7 Promote employee and employer education about disaster preparedness at work and at home.
5.4 MITIGATION OBJECTIVES
The LHMP team selected the objectives listed below to meet multiple goals. The objectives serve as a stand-alone measurement of a mitigation action rather than as a subset of a goal.
Achievement of the objectives is a measure of the effectiveness of a mitigation strategy. The objectives are also used to help establish priorities. When combined, objectives are defined as short-term aims that form a course of action to meet a goal. Unlike goals, objectives are specific and measurable.
The County of Yolo Hazard Mitigation Team identified this list of objectives:
1. Consider the impacts of hazards on future land use decisions in Yolo County by coordinating with other planning mechanisms, including the General Plan and land use code developments.
2. Protect and sustain reliable local emergency operations and communication facilities during and after a disaster.
3. Develop new or enhance existing early warning response systems.
4. Seek to enhance emergency response capabilities through improvements to infrastructure and County programs.
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5. Seek to enhance our understanding of how hazards and disasters may disproportionately impact certain members of our community and identify ways to build community resilience.
6. Seek mitigation projects that provide the highest degree of hazard protection at the least cost.
7. Seek to update information on hazards, vulnerabilities, and mitigation measures by coordinating planning efforts and creating partnerships with appropriate local, state, and federal agencies.
8. Seek to implement codes, standards, and policies that will protect life, property and quality of life including environmental, historic, and cultural resources from the impacts of hazards within Yolo County.
9. Educate the community on preparedness for and mitigation of potential impacts of hazards to Yolo County.
10. Encourage retrofit, purchase, or relocation of structures in high hazard areas, including those known to be repetitively damaged.
11. Eliminate or minimize disruption of local government operations caused by known hazards.
12. Consider open space land uses within identified high-hazard risk zones.
13. Retrofit, acquire, or relocate identified high-risk structures, including those known to experience repetitive losses.
14. Establish a partnership among appropriate levels of government and the business community to improve and implement methods to protect property.
15. Encourage hazard mitigation measures that promote and enhance natural processes and minimize adverse impacts on the ecosystem.
16. Promote and implement hazard mitigation plans and projects that are consistent with state, regional, and local climate action and adaptation goals, policies, and programs.
5.5 MITIGATION ALTERNATIVES
Hazard mitigation alternatives were developed to present a broad range of alternatives to be considered in the planning area, in compliance with 44 CFR (Section 201.6(c)(3)(ii)). One 484
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“catalog” of alternatives was developed for each natural hazard of concern evaluated in this plan.
The catalogs present alternatives that are categorized in two ways:
By whom would have responsibility for implementation:
• Individuals (personal scale)
• Businesses (corporate scale)
• Government (government scale)
By what the alternative would do:
• Manipulate the hazard
• Reduce exposure to the hazard
• Reduce vulnerability to the hazard
• Increase the ability to respond to or be prepared for the hazard.
The catalogs list what could be considered to reduce risk from natural hazards in the planning area. They include practices that will mitigate current risks from hazards or help reduce new risks resulting from climate change. Hazard mitigation actions recommended in this plan were selected from analyzing the best practices presented in the catalogs. The catalogs provide a baseline of mitigation alternatives backed by a planning process and consistent with the established goals and objectives. Actions were selected from the catalogs based on an analysis of the County’s ability to implement them. Best practices in the catalog that are not included in the action plan were omitted for one or more of the following reasons:
• The action is not feasible
• The action is already being implemented
• The County cannot implement the action
• There is a more cost-effective alternative
• The action does not have public or political support
The catalogs for each hazard are presented below:
Alternatives to Mitigate the Dam and Levee Failure
Personal-Scale Corporate-Scale Government Scale
Reduce exposure by
relocating out of the
failure inundation
areas.
Learn about risk
reduction for the dam
and levee failure
hazard.
Learn the evacuation
routes for failure
events.
Harden Dams
Maintenance and
strengthening of the
levee.
Flood proof facilities
within inundated areas.
Educate employees on
the probable impacts of
a failure.
Harden Dams.
Maintenance and
strengthening of the
levee.
Retrofit critical
facilities within the
failure inundation
areas.
Map dam failure
inundation areas
Inform the public of
risk reduction
techniques.
Consider the impacts of
climate in assessing the
risk associated with
failure hazard.
Study available data
sets to determine or
develop methodology
to define socially
vulnerable
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Educate yourself on
early warning systems.
communities.
Alternatives to Mitigate the Drought
Personal-Scale Corporate-Scale Government Scale
Drought resistance
landscapes.
Reduce water system
losses.
Practice active water
conservation.
Drought resistance
landscapes.
Reduce water system
losses.
Practice active water
conservation.
Groundwater recharge
through stormwater
management.
Identify and create
groundwater backup
sources.
Reduce water system
losses.
Public education on
drought resistance.
Develop drought
contingency plans.
Develop criteria
triggers for droughtrelated actions.
Study available data
sets to determine or
develop methodology
to define socially
vulnerable
communities.
Alternatives to Mitigate the Earthquake
Personal-Scale Corporate-Scale Government Scale
Retrofit structures.
Secure household items
that cause injury or
damage.
Practice “drop, cover,
and hold”.
Build redundancy for
critical functions.
Retrofit critical
buildings and areas for
critical function.
Develop a continuity of
operations plan.
Harden infrastructure.
Provide redundancy of
critical functions.
Provide hazard maps.
Study available data
sets to determine or
develop methodology
to define socially
vulnerable
communities.
Adopt higher
regulatory standards.
Include retrofitting and
replacement of critical
infrastructure into the
capital improvement
budget.
Develop a continuity of
operations plan.
Alternatives to Mitigate the Flood
Personal-Scale Corporate-Scale Government Scale
Clear storm drains and
culverts.
Elevate utilities above
the flood base.
Flood proof structures.
Clear storm drains and
culverts.
Build redundancy for
critical functions.
Retrofit critical
buildings.
Maintain drainage
system.
Promote open space use
in identifying highhazard areas.
Harden infrastructure.
Produce hazard maps.
Provide technical
assistance and
guidance.
Train emergency
responders.
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Purchase flood
insurance. Support and implement
hazard disclosure for
property sale in flood
risk zones.
Study available data
sets to determine or
develop methodology
to define socially
vulnerable
communities.
Alternatives to Mitigate the Land Subsidence
Personal-Scale Corporate-Scale Government Scale
Moving well fields to
tap more permeable
(less compressible)
deposits.
Import substitute
surface water.
Conserving water
through improving
irrigation methods.
Recirculating and reuse
of treated water.
Improving water
irrigation methods in
Agriculture – overhead
sprinkler irrigation or
drip irrigation,
Changing crops that
those that require less
water demands.
Repressuring of
aquifers through wells.
Adopt regulations
around well fields –
locations, and changing
depth range of
perforated intervals to
tap less compressible
deposits.
Adopt land use policies
that prohibit the
placement of wells in
high-risk zones.
Produce hazard maps.
Provide technical
assistance and
guidance.
Educate the public on
the land subsidence
hazard and appropriate
risk reduction
alternatives.
Study available data
sets to determine or
develop methodology
to define socially
vulnerable
communities.
Alternatives to Mitigate the Severe Weather (Wind/Tornado, Freeze, Fog, Heat) Personal-Scale Corporate-Scale Government Scale
Insulate house.
Plant appropriate
vegetation.
Trim and remove trees
that could affect
powerlines.
Obtain NOAA radio.
Relocate critical
infrastructure.
Install tree wire.
Trim and remove trees
that could affect
powerlines.
Harden infrastructure,
locating utilities
underground.
Trim and remove trees
that could affect
powerlines.
Modify land use and
environmental
regulations to support
vegetation management
activities.
Establish and enforce
stricter building codes
that support climate
adaptation.
Modify landscape and
other ordinances to
encourage appropriate
planning of vegetation.
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Alternatives to Mitigate the Wildfire
Personal-Scale Corporate-Scale Government Scale
Clean potential fuels on
the property, such as
overgrown underbrush
and trees.
Mow regularly.
Create a defensible
space around all
structures.
Clean potential fuels on
the property, such as
overgrown underbrush
and trees.
Create a defensible
space around all
structures.
Support fire safe
(Firewise) community
initiatives.
Clear potential fuels on
the property, such as
overgrown underbrush
and trees.
Create and maintain
defensible spaces
around all structures.
Consider higher
regulatory standards.
Study available data
sets to determine or
develop methodology
to define socially
vulnerable
communities.
More public outreach
and education efforts.
Create and implement
fire plans.
Consider the impacts of
climate change on the
risk associated with
wildland and urban
interface fire hazards in
future land decisions.
5.6 YOLO COUNTY OPERATIONAL-AREA MITIGATION ACTION PLAN The Steering Committee reviewed the catalogs of hazard mitigation alternatives and selected County-specific actions to be included in a hazard mitigation action plan. The County-specific actions were selected based on the risk assessment of identified hazards of concern and the defined hazard mitigation goals and objectives. Table 5-1 lists the recommended hazard mitigation actions that make up the action plan.
The timeframe indicated in the table is defined as follows:
• Short Term = to be completed in 1 to 3 years
• Long Term = to be completed in greater than 5 years
• Ongoing = currently being funded implement under existing programs Each recommended action was classified based on the hazard it addresses and the type of mitigation it involves. Table shows these classifications. Mitigation types used for this categorization are as follows:
• Prevention—Government, administrative or regulatory actions that influence the way land and buildings are developed to reduce hazard losses. Includes planning and zoning, floodplain laws, capital improvement programs, open space preservation, and stormwater management regulations.
• Property Protection—Modifying buildings or structures to protect them from a hazard or removing structures from a hazard area. Includes acquisition, elevation, relocation, structural retrofit, storm shutters, and shatter-resistant glass. 488
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• Public Education and Awareness—Actions to inform community members and elected officials about hazards and ways to mitigate them. Includes outreach projects, real estate disclosure, hazard information centers, and school-age and adult education. • Natural Resource Protection—Actions that minimize hazard loss and preserve or restore the functions of natural systems. Includes sediment and erosion control, stream corridor restoration, watershed management, forest and vegetation management, wetland restoration and preservation, and green infrastructure. • Emergency Services—Actions that protect people and property during and immediately after a hazard event. Includes warning systems, emergency response services, and the protection of essential facilities.
• Structural Projects—Actions that involve the construction of structures to reduce the impact of a hazard. Includes dams, setback levees, floodwalls, retaining walls, and safe rooms.
• Climate Resiliency—Actions that incorporate methods to mitigate and/or adapt to the impacts of climate change. Includes aquifer storage and recovery activities, incorporating future conditions projections in project design or planning, or actions that specifically address jurisdiction-specific climate change risks, such as sea level rise or urban heat island effect.
• Community Capacity Building—Actions that increase or enhance local capabilities to adjust to potential damage, to take advantage of opportunities, or to respond to consequences. Includes staff training, memorandums of understanding, development of plans and studies, and monitoring programs.
5.6.1 PREVIOUS MITIGATION ACTIONS
Appendix B contains the status of the recommended actions from the 2018 hazard mitigation plan that were removed or completed. Mitigation actions that were incorporated into the 2023 HMP plan were added into Table 5-1. All of the Climate Action mitigation actions have been removed, given the 2023 Yolo County Climate Action and Adaptation Plan Update. Yolo County HMP will be aligning climate change actions previously identified with the 2018 HMP plan into the County’s 2023 Climate Action and Adaption Plan. There has been increased collaboration with the Climate Action and Adaptation team to incorporate hazard mitigation projects as it relates to climate change. A number of other recommended actions in the 2018 hazard mitigation plan were also removed due to significant staff turnover in the County following the COVID-19 Pandemic, or due to a change in priorities, capabilities, or feasibility.
Those projects are listed in Appendix B.
5.6.2 MITIGATION ACTION SUCCESS STORIES
Since the MJHMP was adopted in 2018, there have been many efforts to decrease the vulnerability in each participating jurisdiction whether that be more transparency regarding hazard mitigation awareness on jurisdictional websites, or grant applications to fund mitigation 489
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projects. Successful mitigation projects are highlighted in specific jurisdictional annexes (Volume 2). Some successful mitigation projects include collaborations between Yolo County OES and specific jurisdictions. Projects include backup generators in the Town of Yolo or for the Yolo County Housing Authority spaces to improve system reliability, or the Madison Flood reduction project that is moving towards the design stages of a regional stormwater detention/retention basin to reduce flooding along State Highway 16 that runs between the Town of Esparto, Madison, and Interstate 505. There has also been collaboration between the Climate Action and Adaptation Planning team to not only provide greater education to our communities on mitigation measures but also the effects of climate change on hazards and what the County and Jurisdictions are doing to reduce the effects of climate change, thereby reducing the effects of hazards.
Small Community Flood Risk Reduction Studies
In 2017, as part of the Small Communities Flood Risk Reduction Program, the California Department of Water Resources awarded Yolo County $1.5 million for flood risk reduction studies for the communities of Clarksburg, Knights Landing, and Yolo. These funds were used to identify locally supported projects to improve flood facilities and reduce flood risk. As result, DWR Small Communities Program, completed a study on Knights Landing and a grant application was submitted by Yolo County for ring levee improvements that if constructed would reclassify Knights Landing outside of the 100-year flood plain. The County was awarded $16.1 million to fund critical repairs on the Sacramento River and the design CEQA/NEPA review and permitting for the ring levee.
Knights Landing Flood Management Project
In 2017, Yolo County received a grant from the California Department of Water Resources (DWR) Small Community Flood Risk Reduction Program (SCFFRP) to complete a feasibility study of structural and non-structural actions that could reduce flood risk to Knights Landing. The County prepared the 2019 Knights Landing Small Community Flood Risk Reduction Feasibility Study.
In 2020, the County received additional grant funding from DWR as part of Phase 2 of the SCFRRP to implement the Knights Landing Flood Management Project, which includes four project elements:
1. The design of levee improvements along the Sacramento River adjacent to Knights Landing, the design and permitting of the Knights Landing Ridge Cut levee, and the design and permitting of the Mid-Valley Levee Reconstruction to include the construction of Site 9 & 10.
2. Completion of Phase 1 concepts for Portuguese Bend and Grays Bend Habitat enhancement projects.
3. The design, permitting, and construction of the Drainage Infrastructure Improvements.
4. The design of the New Cross Levee and New Cross Levee Loop Trail. 490
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When the Knights Landing Flood Management Project is completed, it will reduce or prevent flooding to a population of 995, approximately 321 structures, and 3,500 acres of prime agricultural lands (see figure below)
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Figure 5-1: Knights Landing Flood Management Project Proposal Source: Yolo County Dept of Natural Resources
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North Fork Putah Creek Fuel Reduction Project
Minor maintenance activities and emergency tree removals to protect public safety has been undertaken by the County since 2018. However, it was determined that additional maintenance and vegetation removal is necessary to reduce wildfire risk to the surrounding suburban neighborhoods in Davis. This project consists of removal of wildfire fuels (e.g., dead trees/vegetation, downed woody debris, ladder fuels, and dense dry stand of shrubbery) from the North Fork Putah Creek channel, located between Drummond Ave and Mace Boulevard in Davis. The County contracted with the California Conservation Corps to perform the work at no cost of the County. This helps to decrease vulnerability to wildfire risks in Yolo County.
Flood Safe 2.0
As a result of flooding events in 2017 and 2019, Yolo County identified a need for a more comprehensive approach to flood prevention. With funding, the County revived the Flood Safe Yolo program as a new program (2007), Flood Safe Yolo 2.0. The new program is designed to minimize the risk from flooding in Yolo County through strengthened drainage system maintenance, construction of system wide drainage improvements, additional mapping and studies, and support for flood friendly farming practices.
Program elements include:
- Flood Emergency Preparedness
- Flood Hazard Mitigation Projects Planning and Development - Projects Implementation and Maintenance
- Watershed Assessment and Monitoring
- Program Administration and Funding
- Outreach to Yolo County/Stakeholders/Public/Agency/Elected Officials Seismic Retrofitting Projects
Buildings in downtown Woodland are made of masonry and other materials that may not withstand a sizeable earthquake. In particular, the historic buildings on Yolo Avenue. Yolo County has worked with the New Season Community Development Corporation to renovate the structures. To date, seismic upgrades have been made to the Lindberg Building. 493
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Table 5-1: 2023 Yolo County Hazard Mitigation Actions
All Hazard Mitigation Actions
New/
Existing
Action
# Project Goals Hazard Lead Agency
Support
Agency Timeline Funding
Area-wide
Classification
New 1
Continue to maintain a website that
will house the multi-jurisdictional
hazard mitigation plan and any
amendments adopted during the
next 5-year period to provide the
planning partners and the public
with ongoing access to the plan and
its implementation.
1, 2, 3,
4, 5 All Hazards
Yolo County OES
Dept. –
Emergency
Services
Coordinator
Planning
Partners
Short-term,
Estimated
Completion
by 2026
General Funds,
In-kind support,
HMGP
Public Education
and Awareness,
Community
Capacity Building
New 2
Continue to provide a virtual hub
for sharing information on hazard
mitigation resources on the
yolocounty.org/OES website that
will support mitigation efforts and
awareness of grant funding
opportunities to the planning
partnership.
5 All Hazards
Yolo County OES
Dept. –
Emergency
Services
Coordinator
Planning
Partners
Short-term,
ongoing –
Estimated
Completion
for update
by 2025
General Funds,
In-kind support.
HMGP.
Public Education
and Awareness,
Community
Capacity Building
New/
Existing 3
Develop a standardized GIS dataset
for modeling hazards and impacts
for regional and jurisdictional
assessment purposes. Implement a
program to digitally map historical
and future hazard events and
impacts (for example, new fire
hazard severity mapping and social
vulnerability data produced by
federal, state, or local sources that
would apply to the entire planning
area).
2, 3, 4 All Hazards
Yolo County OES
Dept.- Emergency
Services
Coordinator and,
Yolo County IT
Dept.- GIS
Manager
Planning
Partners
Short-term,
Estimated
Completion
by 2025
General Funds,
In-kind support,
HMGP.
Prevention, Public
Education and
Awareness,
Emergency
Services,
Community
Capacity Building
New 4
Encourage the development of and
use of microgrids and the hardening
of the utility of infrastructure, where
possible. Provide backup generators
for critical infrastructure and
facilities.
1,2 Utility
Interruption
Yolo County
Community
Works, Yolo
County General
Services Dept.
Director
Planning
Partners
Short-term,
ongoing,
Estimated
Completion
by 2026
General Funds,
Capital
Improvement
funds.
Property Protection,
Emergency Services
New/ 5 Maintain StormReady certification, 1, 2, 3, Severe Yolo County OES Planning On-going, General Funds, Property Protection, 494
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Hazard Mitigation Plan Update December 2023
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Section 5.0: Mitigation Strategy Yolo Operational Area
All Hazard Mitigation Actions
New/
Existing
Action
# Project Goals Hazard Lead Agency
Support
Agency Timeline Funding
Area-wide
Classification
Existing as applicable. 4, 5 Storms Dept.– Chief of
Emergency
Services
Partners Complete at
renewal
after 4 years
BRIC Emergency Services
New 6
Develop and expand the use and
functionally targeted shelters
County Wide to serve as “All
Hazards Resiliency Centers” which
can serve as an all-hazard resource
for community members.
1, 4 All Hazards
Yolo County
Health and
Human Services –
ESF 6: Mass Care
Coordination
Team Lead
Planning
Partners
Long Term,
Estimated
Completion
by 2028
General Funds,
In-kind support.
Community
Capacity Building
New 7
Continue to
leverage/support/enhance ongoing
public education and awareness
programs to educate the public on
risk, risk reduction, and community
resilience.
5 All Hazards
Yolo County OES
Dept. –
Emergency
Services
Coordinator and
Planner
Planning
Partners
Long-term,
ongoing,
Estimated
Completion
by 2028
General Funds,
In-kind support.
Public Education
and Awareness,
Community
Capacity Building
New 8 Develop a multilingual and
culturally appropriate business
outreach program, in concert with
existing business organizations and
planning partners, to educate
businesses on risk and risk
reduction and to identify policies
and programs to help businesses
become more resilient.
1, 5 All Hazards
Yolo County OES
Dept. –
Emergency
Services
Coordinator and
Planner
Planning
Partners
Short-term,
Estimated
Completion
by 2025
General Funds,
In-kind support.
Public Education
and Awareness,
Community
Capacity Building
Existing 9
Incorporate and make consistent
other planning documents with
appropriate goals, policies, and
objectives to address hazards
identified within the MultiJurisdictional Hazard Mitigation Plan.
3, 4, 5 All Hazards
Yolo County,
Cities, Special
Districts, Planning
Team Leads from
Cities
Planning
Partners
Short-term,
ongoing,
Estimated
Completion
by 2026
General funds,
HMGP, BRIC
Prevention,
Community
Capacity Building
New/
Existing
10 Updating hazard maps, identifying
areas of vulnerability in the Levee
systems.
2, 5 Levee/Dam
Failure
Yolo County
Flood Control and
Water Resource
District Manager,
Yolo County
Community
State
DWR,
Army
Corp
Engineer
s, KSN
Short-term,
ongoing,
Estimated
Completion
by 2026
General funds,
Capital
Improvement
fund, BRIC,
FMA
Prevention,
Emergency
Services,
Community
Capacity Building
495
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Hazard Mitigation Plan Update December 2023
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Section 5.0: Mitigation Strategy Yolo Operational Area
All Hazard Mitigation Actions
New/
Existing
Action
# Project Goals Hazard Lead Agency
Support
Agency Timeline Funding
Area-wide
Classification
Works Dept,
Special District
Managers
New/Ex
isiting 11
Maintain County owned and
jurisdictional-owned drainage
systems with regular maintenance,
inspection, and replacement.
1, 2, 3,
5 Levee/Dam
Failure
Yolo County
Community
Works Dept –
Director, OA
Jurisdiction
Managers, Special
District Managers
Planning
Partners
Ongoing,
Estimated
Completion
by 2028
General funds,
Capital
Improvement
funds, FMA
Property Protection,
Structural Projects
Existing 12
Continue collaborating across the
operational area with all
jurisdictions with fire protection and
suppression responsibility on
wildfire mitigation efforts.
1, 2, 5 Wildfire
Yolo County OES
Dept. Emergency
Services
Coordinator, Yolo
County Rural Fire
Department Fire
Chiefs, Fire Safe
Council Members
Planning
Partners
On-going,
Estimated
Completion
by 2028
General funds,
In-kind support,
Cal-Fire
Wildfire
Prevention
Grants
Natural Resource
Protection,
Structural Projects,
Community
Capacity Building
New 13
Reduction of fire risk through
hazardous fuel reduction projects
including but not limited to land use
practices of controlled burns,
hazardous fuel removal, other
shaded fuels in high risk fire zones.
1, 2,3,
5 Wildfire
Fire Safe Counsel,
Rural Fire
Departments, OA
Fire Departments,
Fire Chiefs
Planning
Partners
Short Term,
Estimated
Completion
by 2025
General funds,
In-kind support,
Cal-Fire
Wildfire
Prevention
Grants
Natural Resource
Protection,
Structural Projects
New 14
Improve road signs and address
marking to increase visibility reduce
response times, and create
awareness or fire risk in high fire
risk zones.
1, 5 Wildfire
Fire Safe Counsel,
Rural Fire
Departments, OA
Fire Departments,
Fire Chiefs
Planning
Partners
Short Term,
Estimated
Completion
by 2025
General funds,
In-kind support,
Cal-Fire
Wildfire
Prevention
Grants
Emergency Services
New 15
Provide public information on water
conservation and assess the
potential for community-wide water
conservation programs.
1, 2, 4,
5 Drought
Yolo County
Community
Works Dept –
Director, Yolo
County Flood
Control and Water
Resource District
Planning
Partners
Long-term,
ongoing,
Estimated
Completion
by 2028
General funds,
DWR Grant,
Floodplain
Management
Protection
Grant
Public Education
and Awareness,
Community
Capacity Building
496
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Hazard Mitigation Plan Update December 2023
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Section 5.0: Mitigation Strategy Yolo Operational Area
All Hazard Mitigation Actions
New/
Existing
Action
# Project Goals Hazard Lead Agency
Support
Agency Timeline Funding
Area-wide
Classification
Manager, Special
District Manager,
City Managers
New 16
Promote more effective use of
groundwater storage through
increase groundwater recharge and
conjunctive use among agencies in
our known drought areas.
1, 2, 3,
4 Drought
Yolo County
Community
Works Dept –
Director, Yolo
County Flood
Control and Water
Resource District
Manager, Special
District Managers,
City Managers
Planning
Partners
Long-term,
Estimated
Completion
by 2028
General Funds,
DWR Grant
Natural Resource
Protection
New 17
Review and update response plans
in light of climate change (heat
event) projections.
2, 4, 5
Severe
Weather:
Extreme
Heat/Extreme
Freeze
Yolo County OES
Dept. –
Emergency
Services
Coordinator and
Planner
Planning
Partners
Short-term,
ongoing,
Estimated
Completion
by 2025
General funds,
HMGP
Prevention, Climate
Resiliency
New 18
Develop and expand the use and
functionally targeted shelters
County Wide to serve as “All
Hazards Resiliency Centers” which
can serve as an all-hazard resource
for community members.
1, 2, 3
Severe
Weather:
Extreme
Heat/
Extreme
Freeze
Yolo County
Health and
Human Services,
Cities – ESF 6:
Mass Care
Coordination
Team Lead
Planning
Partners
Long Term,
Estimated
Completion
by 2028
General Funds,
In-kind support
Community
Capacity Building
New 19 Provide NOAA radios to the public 1
Severe
Weather:
Extreme
Heat,
Extreme
Freeze
Yolo County
Health and
Human Services –
Emergency
Preparedness
Coordinator, City
Managers
Planning
Partners
Short Term,
Estimated
Completion
by 2024
General funds,
Emergency
Preparedness
Grant Funds
(CDPH)
Public Education
and Awareness,
Community
Capacity Building,
Emergency Services
New/
Existing
20 Maintain a good standing in the
National Flood Insurance Program,
particularly the Community Rating
System, and encourage coordination
2, 3, 4,
5 Flooding
Yolo County
Assessor, Yolo
County
Community
Planning
Partners
Short-term,
ongoing,
Estimated
Completion
General funds,
FMA
Prevention, Property
Protection, Public
Education an
Awareness,
497
2023 Yolo Multi-Jurisdictional
Hazard Mitigation Plan Update December 2023
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Section 5.0: Mitigation Strategy Yolo Operational Area
All Hazard Mitigation Actions
New/
Existing
Action
# Project Goals Hazard Lead Agency
Support
Agency Timeline Funding
Area-wide
Classification
on drainage system maintenance. Works – Chief
Building Official,
Yolo County
Administration
by 2024 Structural Projects
New 21
Develop and acquire a vacant land
and promote open space uses in
developing watersheds to control
increase runoff, preventing localized
road flooding.
2, 3, 4,
5 Flooding
Yolo County
Community
Works Dept,
Director, Yolo
County Flood
Control and Water
District Manager,
Special Districts
Manager
Planning
Partners
Long Term,
Estimated
Completion
by 2028
General funds,
DWR grant
Prevention, Natural
Resource Protection
New 22
Elevate roads that are critical to
access and egress, and are in known
to flood.
1, 2, 3 Flooding
Yolo County
Community
Works Dept. -
Director
Planning
Partners
Long Term,
Estimated
Completion
by 2028
General Funds,
Capital
Improvement
funds, DWR
grant funds
Property Protection,
Structural Projects
New/
Existing 23
Provide information on earthquake
risk and preparedness to the public.
Continue to adopt and implement
current earthquake building
standards and upgrade, remove, or
replace unreinforced masonry
buildings as feasible.
1, 2, 4,
5 Earthquake
Yolo County OES
Dept. Chief of
Emergency
Services, Yolo
County
Administration,
Yolo County
Community
Works Dept.
Director
Planning
Partners
Long-term,
ongoing,
Estimated
Completion
by 2028
General funds
Public Education
and Awareness,
Prevention, Property
Protection,
Structural Projects
New 24
Include retrofitting and replacement
of critical infrastructure into capital
budget planning.
3 Earthquake
Yolo County
General Services
Dept. Director,
City Managers
Planning
Partners
Long Term,
Estimated
Completion
by 2028
General Funds
Prevention, Property
Protection,
Structural Projects
New 25
Develop a heat reduction program
that includes urban forestry
planning. 1, 3, 4
Severe
Weather –
Heat
Yolo County
Climate Action &
Adaptation
Committee
Manager, Yolo
Planning
Partners
Long-term,
Estimated
Completion
by 2028
General Funds,
Capital
Improvement
funds
Natural Resource
Protection, Climate
Resiliency
498
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Hazard Mitigation Plan Update December 2023
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Section 5.0: Mitigation Strategy Yolo Operational Area
All Hazard Mitigation Actions
New/
Existing
Action
# Project Goals Hazard Lead Agency
Support
Agency Timeline Funding
Area-wide
Classification
County General
Services Dept.
Director, City
Managers
New 26
Harden infrastructure to support
underground utilities, prevent
damage during Tornado event
1, 3
Severe
Weather –
Wind,
Tornado
Yolo County
General Services,
Yolo County
Community
Works Dept.
Director, City
Public Works
Dept., PGE
Planning
Partners
Long Term,
Estimated
Completion
by 2028
General Funds,
Capital
Improvement
funds
Property Protection,
Structural Projects
New 27
Trim Back trees and heavy shrubby
from power lines, prevent further
damage during Tornado Event
1, 4
Severe
Weather –
Wind,
Tornado
Yolo County
General Services,
Yolo County
Community
Works Dept.
Director, City
Public Works,
PGE
Planning
Partners
Long Term,
Estimated
Completion
by 2028
General funds,
In-kind support,
BRIC
Property Protection
New 28
Planning for and maintaining ability
for adequate road and debris
clearing capabilities.
1, 4
Severe
Weather –
Fog
Yolo Community
Works Dept.
Director, City
Public Works,
CalTrans
Planning
Partners
Long term,
Estimated
Completion
by 2028
General funds,
In-kind support,
BRIC
Prevention,
Emergency
Services,
Community
Capacity Building
New 29
Producing and distributing family
and traveler emergency
preparedness information about
severe fog weather hazards.
Including safety strategies for
severe weather in driver education
classes and materials.
1, 2, 3,
4 Severe
Weather –
Fog
Yolo Community
Works Dept.
Director, City
Public Works
Dept, CalTrans
Planning
Partners
Long term,
Estimated
Completion
by 2028
General funds
Public Education
and Awareness,
Community
Capacity Building
New 30
Adding building insulation to walls
and attics. As buildings are
modified, new technology is used to
create or increase insulation and
efficiency.
1, 3, 5
Severe
Weather -
Freeze
Yolo County
Community
Works Dept, Yolo
County General
Services Manager,
Planning
Partners
Long term,
Estimated
Completion
by 2028
General funds,
Capital
Improvement
Funds
Property Protection,
Structural Projects
499
2023 Yolo Multi-Jurisdictional
Hazard Mitigation Plan Update December 2023
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Section 5.0: Mitigation Strategy Yolo Operational Area
All Hazard Mitigation Actions
New/
Existing
Action
# Project Goals Hazard Lead Agency
Support
Agency Timeline Funding
Area-wide
Classification
City Managers
New 31
Improve data and mapping, Using
GIS to identify and map land
subsidence hazard areas.
1, 2 Land
Subsidence
Yolo County IT –
GIS Manager,
Yolo County
Community
Works Dept.
Director
Planning
Partners
Short Term,
Estimated
Completion
by 2025
In-kind support,
General Funds,
HMP
Prevention, Public
Education and
Awareness,
Community
Capacity Building
New 32
Adopt regulations around well fields
– locations, and changing depth
range of perforated intervals to tap
less compressible deposits.
1, 2 Land
Subsidence
Yolo County
Administration,
Yolo County
Community
Works Dept.
Director
Planning
Partners
Long Term,
Estimated
Completion
by 2028
BRIC, HMP,
General Funds
Prevention, Natural
Resource Protection
New - 2023 Yolo County HMP Update All All Hazards
Yolo County OES
– Emergency
Services
Coordinator
HMP
Planning
Partners
and
Stakehol
ders
Long Term,
Estimated
Completion
by 2028
General Funds,
HSGP, HMP
Prevention, Public
Education and
Awareness,
Community
Capacity Building
Existing -
Convene Local/Tribal Disaster
Councils
(Status: Re-establishing due to staff
turnover)
2,3,4,5 All Hazards
Yolo County OES
– Chief of
Emergency
Services
OA
Partners
Short Term,
On-going,
Estimated
Completion
by 2024
General Funds,
In-kind support
Prevention, Public
Education and
Awareness,
Community
Capacity Building
Existing -
All Hazards Public Awareness and
Disaster Preparedness (Element of
CRS Program)
(Status: Cycle Verification in 2024
to increase CRS rating)
2, 3, 4,
5 All Hazards
Yolo County OES
– Emergency
Services
Coordinator/Plann
er
HMP
Stakehol
ders, PIO
Long Term,
Ongoing
Estimated
Completion
by 2028
General Funds,
HSGP, HMP,
In-kind support
Prevention, Public
Education and
Awareness,
Community
Capacity Building
Existing -
Integrate Local Hazard Mitigation
Plan into Safety Element of General
Plan
(Status: Review after 2023 HMP
Update)
All All Hazards
Yolo County OES
– Chief of
Emergency
Services
City of
Davis,
W.Sac,
Winters,
Woodlan
d
Short Term,
Ongoing,
Estimated
Completion
by 2024
General Funds
Prevention, Public
Education and
Awareness,
Community
Capacity Building
Existing - Care and Shelter Planning to 4, 5 All Hazards Yolo County Yolo Short Term, General Funds Prevention, Public 500
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Hazard Mitigation Plan Update December 2023
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Section 5.0: Mitigation Strategy Yolo Operational Area
All Hazard Mitigation Actions
New/
Existing
Action
# Project Goals Hazard Lead Agency
Support
Agency Timeline Funding
Area-wide
Classification
include People with Disabilities, the
Elderly, Access and Functional
Needs, and Animals
(Status: Review due to staff
turnover, new ESF#6 team)
HHSA – ESF#6
Mass Care Team
Lead
County
OES
Ongoing,
Estimated
Completion
by 2024
Education and
Awareness,
Community
Capacity Building
Existing -
Indian Valley Dam Upgrades
(Status: Preliminary planning
conducted)
1,2 Dam Failure YCFCWCD
Manager
Yolo
County
Commun
ity
Works
Dept.
Long Term,
Estimated
Completion
by 2028
PDM, HGMP Property Protection,
Structural Projects
Existing -
Capay Valley Diversion Dam (West
Adam and Winters Headworks)
Upgrades
(Status: Preliminary planning
conducted)
1,2 Dam Failure YCFCWCD
Manager
Yolo
County
Commun
ity
Works
Dept.
Long Term,
Estimated
Completion
by 2028
YCFCWCD
Capital
Improvement
Funds
Property Protection,
Structural Projects
Existing -
Drought Contingency Plan
(Status: Review due to staff
turnover)
All Drought
Yolo County
Floodplain
Manager
Yolo
County
OES
Short-term,
Estimated
Completion
by 2025
PDM, HMGP,
General Funds,
In-kind support
Prevention, Public
Education and
Awareness,
Community
Capacity Building
Existing -
Drought Mitigation Plan
(Status: In-discussion due to CAAP
update and 2023 HMP update)
All Drought
Yolo County
Floodplain
Manager
Yolo
County
OES
Dept.
Short-term,
Estimated
Completion
by 2025
PDM, HMGP,
General Funds,
In-kind support
Prevention, Public
Education and
Awareness,
Community
Capacity Building
Existing -
Cacheville Well Replacement
(Status: Preliminary planning
completed)
1,2 Drought
Yolo
County/Cachevill
e Community
Services District
Manager
Yolo
County
Commun
ity
Works
Dept.
Long-term,
Estimated
Completion
by 2028
PDM, HMGP,
General Funds
Property Protection,
Structural Projects
Existing -
Groundwater Wells
(Status: Planning has Not started,
Conceptual phase)
1,2,4 Drought RD108 District
Manager
Yolo
County
Commun
Long-term,
Estimated
Completion
USBR, PDM,
HMGP
Property Protection,
Structural Projects
501
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Hazard Mitigation Plan Update December 2023
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Section 5.0: Mitigation Strategy Yolo Operational Area
All Hazard Mitigation Actions
New/
Existing
Action
# Project Goals Hazard Lead Agency
Support
Agency Timeline Funding
Area-wide
Classification
ity
Works
Dept.
by 2028
Existing -
Forbes Ranch Regulating Pond
(Status: Preliminary Design
Complete)
1,2 Flooding/Dro
ught
YCFCWCD
Manager
Yolo
County
Commun
ity
Works
Dept.
Short-term,
Estimated
Completion
by 2025 SGMA, USBR Property Protection,
Structural Projects
Existing - North Winters Retention Pond
(Status: Conceptual) 1,2 Flooding/Drought
YCFCWCD
Manager
City of
Winters
Public
Works
Short-term,
Estimated
Completion
by 2025
PDM, HMGP,
SGMA
Property Protection,
Structural Projects
Existing -
Cache Creek Flooding
(Status: on-going project with
DWR)
1,2 Flooding/Lev
ee Failure
Woodland Public
Works Director
Yolo
County
Commun
ity
Works
Dept.
Long-term,
Estimated
Completion
by 2028
DWR Grants Property Protection,
Structural Projects
Existing - Promote NFIP
(Status: on-going project) All Flooding
Yolo County
Community
Works Dept.
Director
Davis,
Woodlan
d,
Winters,
W.Sac
Long-term,
Estimated
Completion
by 2028
General Funds
Prevention, Public
Education and
Awareness,
Community
Capacity Building
Existing -
Madison House Elevation
(Status: Project to elevate all houses
in Madison (147) out of the 100-
year floodplain, planning initiated)
1,2 Flooding/Lev
ee Failure
Yolo County
Housing
Authority
Director
Yolo
County
Commun
ity
Works
Dept.
Long-term,
Estimated
Completion
by 2028
FMA, HMGP,
HMP
Property Protection,
Structural Projects
Existing -
Madison Stormwater Management
(Status: Identified potential parcels
for a regional stormwater
detention/retention basin project,
and completed the hydrologic/
hydraulic study. Design phase in
1,2 Flooding/Lev
ee Failure
Yolo County
Community
Works Dept.
Director
Yolo
County
OES
Dept.
Short-term,
Estimated
completion
by 2024
PDM, HGMP Property Protection,
Structural Projects
502
2023 Yolo Multi-Jurisdictional
Hazard Mitigation Plan Update December 2023
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Section 5.0: Mitigation Strategy Yolo Operational Area
All Hazard Mitigation Actions
New/
Existing
Action
# Project Goals Hazard Lead Agency
Support
Agency Timeline Funding
Area-wide
Classification
progress)
Existing
- Stabilization of Sacramento River
Levee Toe
(Status: on-going) 1,2 Flooding/Lev
ee Failure
RD 827 –
Reclamation
District Manager
Yolo
County
OES
Dept.
Long-term,
Estimated
Completion
by 2028
PDM, HMGP Property Protection,
Structural Projects
Existing
- East Bypass Levee Hardening and
Armoring of Pump Plant
(Status: on-going) 1,2 Flooding/Lev
ee Failure
RD 827 –
Reclamation
District Manager
Yolo
County
OES
Dept.
Long-term,
Estimated
Completion
by 2028
PDM, HMGP Property Protection,
Structural Projects
Existing
- Backup Generator
(Status: on-going) 1,2,3 Flooding/Lev
ee Failure
RD 900 –
Reclamation
District Manager
Yolo
County
OES
Dept.
Long-term,
Estimated
Completion
by 2028
HMGP Property Protection,
Structural Projects
Existing
-
Hardening of Blacker Canal Bank
(Status: on-going) 1,2 Flooding/Levee Failure
RD 900 –
Reclamation
District Manager
Yolo
County
OES
Dept.
Long-term,
Estimated
Completion
by 2028
HMGP Property Protection,
Structural Projects
Existing
-
SCADA
Implementation (Status: on-going) 1,2 Flooding/Levee Failure RD 900 –
Reclamation
District Manager
Yolo
County
OES
Dept.
Long-term,
Estimated
Completion
by 2028
HMGP Property Protection,
Structural Projects
Existing
- Hardening of Bridgeway Lakes
Drainage canal
(Status: on-going) 1,2 Flooding/Lev
ee Failure
RD 900 –
Reclamation
District Manager
Yolo
County
OES
Dept.
Long-term,
Estimated
Completion
by 2028
HMGP Property Protection,
Structural Projects
Existing
- Seepage mitigation of Sacramento
River levee
(Status: Design and Permitting
initiated)
1,2 Flooding/Lev
ee Failure
RD108 –
Sacramento
River West Side
Levee District
Manager
Yolo
County
OES
Dept.
Long-term,
Estimated
Completion
by 2028
DWR Grant,
Local Cost
Share, PDM,
HMGP
Property Protection,
Structural Projects
Existing
- Hardening of Sacramento River
Levee
(Status: Problem Identification
initiated)
1,2 Flooding/Lev
ee Failure
Yolo County /
RD108-
Sacramento River
West Side Levee
District Manager
Yolo
County
OES
Dept.
Long-term,
Estimated
Completion
by 2028
DWR grant
PDM, HMGP
Property Protection,
Structural Projects
Existing - Armoring of East Bypass Levee 1,2 Flooding/Lev RD 1600 – Yolo Long-term, PDM, HMGP Property Protection, 503
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Hazard Mitigation Plan Update December 2023
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Section 5.0: Mitigation Strategy Yolo Operational Area
All Hazard Mitigation Actions
New/
Existing
Action
# Project Goals Hazard Lead Agency
Support
Agency Timeline Funding
Area-wide
Classification
(Status: ongoing) ee Failure Reclamation
District Manager
County
OES
Dept.
Estimated
Completion
by 2028
Structural Projects
Existing
- Hardening of Cross Levee
(Status: ongoing) 1,2 Flooding/Lev
ee Failure
RD 2035 –
Reclamation
District Manager
Yolo
County
OES
Dept.
Long-term,
Estimated
Completion
by 2028
PDM, HMGP Property Protection,
Structural Projects
Existing
-
Siphon Upgrade
(Status: planning phase) 1,2 Flooding/Lev
ee Failure
RD2035 –
Reclamation
District Manager
Yolo
County
OES
Dept.
Long-term,
Estimated
Completion
by 2028
PDM, HMGP Property Protection,
Structural Projects
Existing
- Emergency
Generator – Pump Stations
(Status – Design initiated) 1,2 Flooding/Lev
ee Failure
RD108 –
Reclamation
District Manager
Yolo
County
OES
Dept.
Long-term,
Estimated
Completion
by 2028
PDM, HMGP Property Protection,
Structural Projects
Existing
- Stabilization of Colusa Basin Drain
Levee
(Status: Problem Identification
phase)
1,2 Flooding/Lev
ee Failure
RD108 –
Reclamation
District Manager
Yolo
County
OES
Dept.
Long-term,
Estimated
Completion
by 2028
DWR grant
PDM, HMGP
Property Protection,
Structural Projects
Existing
- Hardening of Knights Landing
Ridge Cut Levee
(Status: Problem Identification
phase)
1,2 Flooding/Lev
ee Failure
RD108 – Knights
Landing Ridge
Drainage District
Manager
Yolo
County
OES
Dept.
Long-term,
Estimated
Completion
by 2028
DWR grant
PDM, HMGP
Property Protection,
Structural Projects
Existing
- Hardening of Colusa Basin Drain
Levee
(Status: Problem Identification
phase)
1,2 Flooding/Lev
ee Failure
RD 108 –
Reclamation
District Manager
Yolo
County
OES
Dept.
Long-term,
Estimated
Completion
by 2028
DWR grant
PDM, HMGP
Property Protection,
Structural Projects
Existing
-
Flood Basin Segmentation
(Status – Study initiated) 1,2 Flooding/Levee Failure
Yolo County /
RD108 – Knights
Landing Ridge
Drainage District
Manager
Yolo
County
OES
Dept.
Long-term,
Estimated
Completion
by 2028
DWR grant
PDM, HMGP
Property Protection,
Structural Projects
Existing
- RD 537 Pump Station Upgrades
(Status: Design phase) 1,2 Flooding/Lev
ee Failure
City of West
Sacramento
Public Works /
Yolo County / RD
Yolo
County
OES
Dept.
Long-term,
Estimated
Completion
by 2028
HMGP Property Protection,
Structural Projects
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All Hazard Mitigation Actions
New/
Existing
Action
# Project Goals Hazard Lead Agency
Support
Agency Timeline Funding
Area-wide
Classification
537 –
Reclamation
District Manager
Existing - Emergency Power
(Status: ongoing) 1,2 Severe
Weather
City manager of
Davis, West
Sacramento,
Winters,
Woodland, Yolo
County OES
Chief of
Emergency
Services
Yolo
County
OES
Dept.
Short-term,
Estimated
Completion
by 2025
Completed/D
eleted It
PDM, HMGP
ems
Property Protection
Existing -
Winter Weather Preparedness
Campaign
(Status: ongoing, done every
Winter)
3,4 Severe
Weather
Yolo County OES
– Emergency
Services
Coordinator, PIO
OA
Planning
Partners
Short-term,
Estimated
Completion
by 2024
General fund
Prevention, Public
Education and
Awareness,
Community
Capacity Building
Existing -
Fuel Reduction in Local
Responsibility Areas
(Status: ongoing)
1,2 Wildfire
City Fire Chiefs –
Davis, Winters,
West Sac,
Woodland, Yolo
County OES
Emergency
Services Chief
OA
Planning
Partners
Long-term,
Estimated
Completion
by 2028
CalFire Grants,
Fire Safe
Council Grants,
HMGP
Prevention, Capacity
Building
Existing -
State Route 128 Fire Prevention
(Status: Working with CalTrans and
CalFire to reduce vegetative fuels) 1,2 Wildfire Winters Fire Chief
Yolo
OES
Long-term,
Estimated
Completion
by 2028
CalFire Fire
Prevention
Grant, PDM,
HMGP
Prevention, Capacity
Building
Existing -
Wildfire Mitigation Plan
(Status: includes effects of climate
change, currently undergoing
review for update)
1,2,3,5 Wildfire
Yolo County OES
– Emergency
Services Chief
OA
Partners,
City Fire
Chiefs
Short-term,
Estimated
completion
by 2024
PDM, HMGP
Prevention, Public
Education and
Awareness,
Community
Capacity Building
Existing -
Indian Valley Dam Power Pole
Upgrade
(Status: ongoing)
1,2 Wildfire YCFCWCD
Manager
Yolo
OES
Long-term,
Estimated
Completion
PDM, HMGP,
HMP
Property Protection,
Structural Projects
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All Hazard Mitigation Actions
New/
Existing
Action
# Project Goals Hazard Lead Agency
Support
Agency Timeline Funding
Area-wide
Classification
by 2028
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5.7 MITIGATION ACTION PRIORITIZATION
This Plan promotes 33 action items. The list below summarizes all of the actions, identifies the hazard(s) each one addresses, and indicates the assigned priority level of the action. The actions were prioritized in the same way that they were identified. The planning team proposed an initial prioritization system, dividing the actions into Very High Priority, High Priority, and Important categories. County staff, committee, and community members were allowed to review these categorizations. FEMA’s recommended prioritization criteria, STAPLEE, assisted in deciding why one recommended action might be more important, more effective, or more likely to be implemented than another.
STAPLEE stands for the following:
• Social: Does the measure treat people fairly? Does it consider social equity, disadvantaged communities, or vulnerable populations?
• Technical: Will it work? Is the action feasible? Does it solve the problem? • Administrative: Is there a capacity to implement and manage the project? Is there adequate staffing, funding, and other capabilities to implement the project? • Political: Who are the stakeholders? Did they get to participate? Will there be adequate political and public support for the project?
• Legal: Does the jurisdiction have the legal authority to implement the action? Is it Legal? Are there liability implications?
• Economic: Is there action cost-beneficial? Is there funding available? Will the action contribute to the local economy?
• Environmental: Does the action comply with environmental regulations? Will there be negative environmental consequences from the action?
Additional factors were considered when assigning priorities, as further described below. Those actions with strong community support and addressing hazards presenting the highest risk to Yolo County were given Very High or High priority ratings. Based on the updated vulnerability assessments, levee failure, wildfires, earthquakes, and floods have the most potential to cause great economic and human losses; therefore, actions related to these hazards were generally assigned Very High and High Priority. While there is some estimated dollar loss calculation for the risk of drought, due to agricultural costs, water supply is essential to the survival of the County; therefore, drought and threats to the water system were ranked as Very High Priority.
Loss calculations for the hazard of land subsidence show a high potential loss value; however, the potential damage from the hazard of land subsidence is generally not catastrophic but would generally result in minor damage to structures. The level of risk from a dam failure is relatively lower; therefore, these hazards were assigned a somewhat lower yet still important priority. The threat of climate change is a long-term phenomenon and there is no loss calculation for this hazard. However, climate change exacerbates the hazards of wildfire, land subsidence, floods, and drought due to changes in seasonal patterns of rainfall and temperature; therefore, actions to 507
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address climate change are an important priority. The number of plan objectives potentially addressed by the action and capability in terms of availability of funding and staffing were important additional factors in priority determination.
Section 201.6(c)(3)(iii) of Title 44 of the Code of Federal Regulations requires that an action plan describe how actions identified were prioritized. The planning team developed a prioritization methodology for the action plan that meets the needs of the County while at the same time meeting the requirements of CFR 201.6(c)(3)(iii). The mitigation strategies identified were prioritized according to the criteria defined below.
Following the Disaster Mitigation Act requirements, an emphasis was placed on the importance of benefit-cost analysis in determining action priority (44 CFR, Section 201.6(c)(3)(iii)). The benefits of proposed actions were weighed against the estimated cost as part of the prioritization process. This is not the detailed level of benefit/cost analysis required for some FEMA hazard related grant programs. A less formal approach was used because the associated costs and benefits could change from year-to-year. Such analysis would be performed at the time a given action is being submitted for grant funding. Therefore, a review of the apparent benefits versus the apparent costs of each project was performed instead. Parameters established for assigning subjective ratings are defined below:
Cost ratings were defined as follows:
• High: existing funding will not cover the project’s cost; implementation would require new revenue through an alternative source.
• Medium: The project could be implemented with existing funding but would require a budget re-apportion or a budget amendment, or the project cost would have to be spread over multiple years.
• Low: The project could be funded under the existing budget. The project is part of/can be part of an ongoing existing program.
Benefit ratings were defined as follows:
• High: The project will immediately reduce risk exposure for life and property. • Medium: The project will have a long-term impact on reducing risk exposure for life property, or the project will provide an immediate reduction in the risk exposure for property.
• Low: Long-term project benefits are difficult to quantify in the short term.
Implementation priority ratings were assigned as follows:
• High Priority—An action that meets multiple objectives, has benefits that exceed costs, and has a secured source of funding. Action can be completed in the short term (1 to 5 years).
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• Medium Priority—An action that meets multiple objectives, has benefits that exceed costs, and is eligible for funding though no funding has yet been secured for it. Action can be completed in Recommended Planning-Area-Wide Actions in the short term (1 to 5 years), once funding is secured. Medium-priority actions become high priority actions once funding is secured.
• Low Priority—An action that will mitigate the risk of a hazard, has benefits that do not exceed the costs or are difficult to quantify, has no secured source of funding, and is not eligible for any known grant funding. Action can be completed in the long term (1 to 10 years). Low-priority actions may be eligible for grant funding from programs that have not yet been identified.
Grant pursuit priority ratings were assigned as follows:
• High Priority—An action that meets identified grant eligibility requirements, has high benefits, and is listed as high or medium implementation priority; local funding options are unavailable or available local funds could be used instead for actions that are not eligible for grant funding.
• Medium Priority—An action that meets identified grant eligibility requirements, has medium or low benefits, and is listed as medium or low implementation priority; local funding options are unavailable.
• Low Priority—An action that has not been identified as meeting any grant eligibility requirements.
The County will pursue implementing these actions to meet the goals set out above. The Very High and High Priority actions will be conducted actively over three to five years as funding becomes available.
Table 5-2: Mitigation Action Priority
Mitigation Action Priority
Action
#
#
Objectives
Met Benefit Cost
Benefits equal
Cost or Exceed
Grant
Eligible
Funded
Under
Program
Budget
Implementation
Priority
Grant
Priority
1 1, 2, 3, 4, 5 High Low Yes Yes Yes High Medium
2 5 High Low Yes No Yes High Low
3 2, 3, 4 High Low Yes No No Medium Low
4 1,2 High High Yes Yes No Medium Medium
5 1, 2, 3, 4, 5 Medium Low Yes No Yes High Low
6 1, 4 High High Yes Yes No Medium Medium
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7 5 Medium Low Yes No Yes High Low
8 1, 5 High Low Yes No Yes High Low
9 3, 4, 5 Medium Low Yes No Yes High Low
10 2, 5 High Low Yes No No Medium Low
11 1, 2, 3, 5 High High Yes No Yes High Low
12 1, 2, 5 High Low Yes No Yes High Low
13 1, 2,3, 5 High High Yes Yes Yes High High
14 1, 5 Medium High No Yes Yes High High
15 1, 2, 4, 5 Medium Low No No No Medium Low
16 1, 2, 3, 4 High High No No No Low Low
17 2, 4, 5 Medium Low Yes No No Medium Low
18 1, 2, 3 High High Yes No No Medium Low
19 1 High High Yes No No Low Low
20 2, 3, 4, 5 Medium High No No No Medium Low
21 2, 3, 4, 5 Medium High No Yes No Low Medium
22 1, 2, 3 Low High No No No Medium Low
23 1, 2, 4, 5 Medium High No No No Low Low
24 3 Low High No No No Medium Low
25 1, 3, 4 Medium High No Yes No Medium Medium
26 1, 3 Medium High No No Yes High Low
27 1, 4 Medium High No No Yes High Low
28 1, 4 Low Low Yes No No Low Low
29 1, 2, 3, 4 Low High No No No Low Low
30 1, 3, 5 Medium High No Yes No Medium Medium
31 1, 2 Medium High Yes No No Low Low
32 1, 2 Medium High Yes No No Low Low
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SECTION 6.0: PLAN ADOPTION, MAINTENANCE, AND
EVALUATION
6.1 FUTURE DEVELOPMENT TRENDS
Yolo County has a strong focus on protecting our agricultural and open space resources, commodities and identity; resisting urbanization; and directing growth into the existing incorporated cities and towns. Over 93% of the County remains in farmland and open space, despite development pressures. Future development goals include modest managed growth within specified existing unincorporated communities, where accompanied by improvements to existing infrastructure and services, as well as by suitable new infrastructure and services (see Figure 6-1); new emphasis on community and neighborhood design requirements that reflect “smart growth” principles and complement the character of existing developed areas; and Yolo County continuing to adopt development standards and designs that account for and help to reduce future climate change.
According to the Yolo Local Agency Formation Commission Municipal Service Review and Sphere of Influence Update for the Yolo Community Services Districts adopted in 2021, the unincorporated areas of Yolo County are estimated to have a 1.0% decrease in growth from January 1, 2019- January 1, 2020. In the town of Yolo, due to the lack of a sewer system and the limited capacity of the water system constrains development. There are plans for future growth outside the town of Yolo, such as land zoned for Highway Service Commercial and Single Family Residential (5-10 residential lots), however until the water and sewer system is expanded, it would not be able to accommodate growth. In Esparto, there is demand for new housing, however Yolo County adopted an updated community plan which downzoned some areas back to agricultural uses and reduced the future community area. However, Esparto does have development potential and efforts since the last HMP update are being made such as the new park and aquatic center that was built in Esparto in 2019. Knights Landing does include some additional land zoned for growth. Infill development in Knights Landing is severely constrained by FEMA identified flood issues. Main living areas are currently required to be constructed on a second story, which is a significant constraint. Madison, the Highway 5 communities of Yolo and Zamora, and Knights Landing have some potential as their populations and highway traffic expand.
From the Yolo County 2021-2029 Housing Element, there has been constraints to lower income housing development in Davis and West Sacramento, due to water and sewer infrastructure constraints as well constraints due to the Yolo Bypass and Yolo Causeway which are 100-year flood zones with flood elevations of approximately 30 feet or more. If there are future developments in this area, the flood hazards for these housing developments would increase and measures would need to be in place for flood protection. 511
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In January 2023, the County Board of Supervisors also amended a Land use element and Conservation and Open Space Element to address climate adaption and resiliency strategies. This included vulnerability assessments that identified climate change-related risks, and a set of adaption resilience goals, policies, and objectives, and a set of implementation measures to avoid or minimize climate change impacts, locate essential public facilities outside of at-risk areas, designate adequate and feasible infrastructure in an at-risk area, and identification of natural infrastructure that may be used in adaptation projects. This update to the land use element and conservation and open space elements, decreases Yolo County’s vulnerability to climate-related risks and protects the current open space areas, as well as designates agricultural production on farmland designated for future development, to reduce the potential for agricultural pests/weeds, and fire hazards.
One of the future goals remains to emphasize the revitalization of Yolo County small downtowns as a key economic development activity. This includes improving local retail and services in Esparto, Knights Landing, Madison, and other communities. These initiatives rely on the support of several grant programs to help with providing public facilities, infrastructure, and affordable housing and will need increased mitigation in public outreach. Effective revitalization depends on adequate water, sewers, roads, fire and public safety. The infrastructure systems of these communities must also be upgraded as an important component of revitalization. Overall, future development goals center around decreasing the impact of these hazards and the impact of climate change on property, assets, and the population of Yolo County. Each year City Planners present future development trends to the County Board of Supervisors and the public, ensuring that these goals are aligning with hazard and climate change reduction efforts to continue to make Yolo County a more sustainable, safe, and healthy place to live for our residents and generations to come.
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Figure 6-1: Residential Developments (Existing and Planned) in Hazard Areas Source: CalFire/Office of the State Fire Marshal, Yolo County GIS Map Date: February 28,2021 513
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6.2 PLAN ADOPTION
A hazard mitigation plan must document that it has been formally adopted by the governing bodies of the jurisdictions requesting federal approval of the plan (44 CFR Section 201.6(c)(5)).
For multijurisdictional plans, each jurisdiction requesting approval must document that is has been formally adopted. This plan will be submitted for a pre-adoption review to Cal OES and FEMA Region IX prior to adoption. Once pre-adoption approval has been provided, all planning partners will formally adopt the plan. DMA compliance and its benefits cannot be achieved until the plan is adopted. Copies of the resolutions adopting this plan for all planning partners can be found in Appendix C of this volume.
6.3 PLAN IMPLEMENTATION AND MONITORING
The effectiveness of a hazard mitigation plan depends on the implementation and incorporation of its action items into existing local plans, policies, and programs. Together, the actions items in this 2023 HMP Update, provide a framework for activities that Yolo County can implement over the next five years. The Planning Team and the Steering Committee have established goals and objectives and have prioritized mitigation actions that will be implemented through existing plans, policies, and programs. Including, but not limited to, Emergency Operations Plans (County and City), Yolo County 2030 General Plan Health and Safety Section, Drought Resiliency Plans. and the NFIP CRS program.
Yolo County Office of Emergency Services will be the agency responsible for monitoring the plan, and each partner will track the status of all mitigation actions in its own action plan. Staff or departments with primary responsibility are identified in each jurisdictional annex (Volume 2). The Annual Progress report process described below, outlines how mitigation actions and measures will continue to be monitored. The Annual progress report creates accountability to ensure the 2023 HMP plan will continued to be implemented and monitored through the giveyear cycle.
ANNUAL PROGRESS REPORT - MONITORING
In order to monitor the implementation of the 2023 HMP over the five-year cycle, a Maintenance Working Group will be created that consists of participating planning partners and led by the Office of Emergency Services, Emergency Services Coordinator. The Maintenance Working Group will convene a bi-annual meeting to evaluate the progress of the mitigation action plan over a six-month and 12-month performance period throughout the five-year cycle. This review will include items such as the following:
• Summary of any hazard events that occurred during the performance period and impact of these events on the planning area
• Review and documentation of mitigation success stories • Review of continued public involvement strategy – website, StoryMap, other ways to engage the public.
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• Brief discussions about why targeted strategies were not completed • Reevaluation of the action plan to establish if the timeline for projects needs to be amended
• Recommendations for new mitigation projects
• Changes in or potential for new funding options including grant opportunities • The impact of any other planning programs or initiatives that involve hazard mitigation such as Climate Action and Adaptation, or other sustainability groups.
Participating Planning partners will be responsible for forwarding this information for the Maintenance Working Group to include in a formal report on the plan’s progress yearly. The Maintenance Working Group will prepare a progress report during the 2023-2024 planning period and each year after until the next hazard mitigation plan update in 2028. This report will be retained by the County OES, with copies forwarded to planning partners, Cal OES, and jurisdictions. This report should be used as follows:
• The reporting period will cover a 12-month period from FEMA’s approval • Annually every year following.
• Only four annual progress reports will be prepared; an updated plan will be prepared for the fifth year, rather than a progress report.
• The plan implementation lead (OES), Emergency Services Coordinator, will send out reminder emails to all planning partners no later than three months before the due date.
Planning partners will submit their status updates and sections of the annual report no later than one month prior to the due date.
• The plan maintenance lead will prepare the annual report, including planning partner information, no later than one month following the progress reporting due date. • OES will ensure the report is posted to the County’s hazard mitigation website. • The report will describe public outreach and engagement made during the reporting period.
• The Maintenance Working Group will use the information in the annual report to identify projects of interest for the following year and to apply for mitigation or resiliency grants. • The Maintenance Working Group will present to the County Board of Supervisors. It will provide the information to the planning partners for them to provide to their governing bodies to inform them of the progress of mitigation and resiliency efforts implemented during the reporting period.
Annual progress is not a requirement of 44 CFR, but it may enhance the planning partners’ opportunity for grant funding as well as tracking the mitigation action strategy. Failure to implement this component of the plan maintenance strategy will not jeopardize a planning partner’s compliance under the DMA; it may jeopardize its opportunity to partner and leverage funding opportunities with other planning partners. The Maintenance Working Group will follow 515
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up with planning partners that do not participate in the annual reporting as deemed necessary by the Yolo County OES.
GRANT MONITORING AND EVALUATION
The County Administration Office and Office of Emergency Services, Chief of Emergency Services, Emergency Services Coordinator/Planner, will identify grant funding opportunities as they arise. Once these opportunities are identified, County stakeholders and the HMP Steering Committee will convene to review the Hazard Mitigation Plan and pursue strategies to capture grant funding to drive mitigation actions. The Office of Emergency Services will assume lead responsibilities for planning and facilitating grant opportunity meetings. Review of the hazard mitigation plan at these meetings can include the following:
• Discussion of any hazard events that occurred during the prior year and their impact on the planning area
• Impact of potential grant opportunities on the implementation of mitigation actions • Re-evaluation of the action plans to determine if the timeline for identified actions needs to be amended (such as changing a long-term action to a short-term action because of funding availability)
• Recommendations for new actions
• Impact of any other planning programs or initiatives that involve hazard mitigation
6.4 PLAN EVALUATION
The plan will be evaluated by how successfully the implementation of identified actions has helped to achieve the goals and objectives identified in the plan. This will be assessed by a review of the changes in risk that occur over the performance period and by the degree to which mitigation goals and objectives are incorporated into existing plans, policies, and programs. Plan evaluation will be the responsibility of the Office of Emergency Services, Emergency Services Coordinator and Emergency Services Planner. The Steering Committee and Planning Partners may also recommend changes to the hazard mitigation plan based on evaluation findings. The plan will be evaluated as part of the Annual progress reporting process.
6.5 PLAN MAINTENANCE
Plan maintenance is the formal process for achieving the following (44 CFR Section 201.6 (c)(4)):
• Ensuring that the hazard mitigation plan remains an active and relevant document and that the planning partnership maintains its eligibility for applicable funding sources • Monitoring and evaluating the plan annually and producing an updated plan every five years
• Integrating public participation throughout the plan maintenance and implementation process
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• Incorporating the mitigation strategies outlined in the plan into existing planning mechanisms and programs, such as any relevant comprehensive land-use planning process, capital improvement planning process, and building code enforcement and implementation.
To achieve these ends, a hazard mitigation plan must present a plan maintenance process that includes the following (44 CFR Section 201.6(c)(4)):
• A method and schedule for monitoring, evaluating, and updating the mitigation plan within a 5-year cycle
• An approach for how the community will continue public participation in the plan maintenance process.
• A process by which local governments will incorporate the requirements of the mitigation plan into other planning mechanisms when appropriate Table 6-1 Summary of the plan maintenance strategy
Plan Maintenance Matrix
Task Approach Timeline Lead Support
Plan
Integration
Integrate relevant information from
the hazard mitigation plan into other
plans and programs where viable as
opportunities arise.
Continuous
over the 5-year
performance
period
Yolo County
OES Dept –
Emergency
Services
Coordinator,
HMP City
Planning
Partners
City Planning
Partner, HMP
Steering Committee
Plan
Monitoring
Prepare status updates and action
implementation tracking for annual
progress reporting. Review annually
at HMP Meetings.
As grant opportunities present
themselves, consider options to
pursue grants to fund actions
identified in this plan.
Annually after
the adoption
and final
approval of the
plan by FEMA.
As grants
become
available.
Yolo County
OES Dept –
Emergency
Services
Coordinator
City Planning
Partner, HMP
Steering Committee
Annual
Progress
Reporting/
Plan
Effectiveness
Evaluation
Review the status of previous
actions submitted by the planning
lead and assess the plan’s
effectiveness; compile the annual
progress report’ to assess
appropriate action for preparing the
next hazard mitigation plan update.
Annually after
the final plan is
approved by
FEMA, or
upon a major
disaster or a
comprehensive
update to a
general plan.
Yolo County
OES Dept –
Emergency
Services
Coordinator,
and all
planning
partners
Designated point of
contact for each
planning partner.
Plan Update Reconvene the planning partners, at
a minimum, every five years to
Every five
years or upon
Yolo County
OES Dept –
Designated point of
contact for each
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guide a comprehensive update and
review and revise the plan.
comprehensive
update to the
general plan or
major disaster.
Emergency
Services
Coordinator,
and All
Planning
Partners
planning partner.
Continuing
Public
Involvement
Provide the public access to the
implementation of this plan,
principally through the plan website
www.yolocounty.org/oes, hold
public meeting review once a year,
receive community comments
through the website. The website
and comments will be maintained
over the course of the plan.
Annually Yolo County
OES Dept –
Emergency
Services
Coordinator
All planning
partners will
provide a link to
County Hazards
Mitigation Plan
website on their
website.
6.6 PLAN UPDATE
The plan maintenance process includes a schedule for monitoring and producing an updated plan every five years. Local hazard mitigation plans must be reviewed, revised if appropriate, and resubmitted for approval to remain eligible for benefits under the DMA (44 CFR, Section 201.6.d.3). The planning partnership intends to update the hazard mitigation plan on a 5-year cycle from the date of initial plan adoption. This cycle may be accelerated to less than 5 years based on the following triggers:
• A presidential disaster declaration that impacts the planning area • A hazard event that causes loss of life
• An update of the County or participating city’s general plan This plan’s format allows sections to be reviewed and updated when new data become available, resulting in a plan that will remain current. It will not be the intent of future updates to develop a completely new hazard mitigation plan for the planning area. To avoid expiration, the partnership will strive to initiate the plan update process with sufficient time to complete the update before the plan expires; the process is recommended to begin a year and a half before the expiration date). The update will, at a minimum, include the following elements:
• The update process will be convened through a steering committee. • The hazard risk assessment will be reviewed and, if necessary, updated using best available information and technologies.
• The action plans will be reviewed and revised to account for any actions completed, dropped, or changed and to account for changes in the risk assessment or new partnership policies identified under other planning mechanisms (such as the general plan).
• The draft update will be sent to appropriate agencies and organizations for comment. • The public will be given an opportunity to comment on the update prior to adoption. 518
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• Planning partners’ governing bodies will adopt their portions of the updated plan.
6.7 CONTINUING PUBLIC INVOLVEMENT
The public will continue to be apprised of the plan’s progress through the Yolo County OES website, including providing copies of annual progress reports on the website. All planning partners have agreed to provide links to the County hazard mitigation plan website on their individual jurisdictional websites to increase avenues of public access to the plan. The County has agreed to maintain the hazard mitigation plan website. This site will house the final plan and serve as a one-stop site for information regarding the plan, the partnership and plan implementation. Upon initiation of future update processes, a new public involvement strategy will be initiated based on guidance from a new steering committee. This strategy will be based on the needs and capabilities of the planning partnership at the time of the update. At a minimum, this strategy will include the use of local media outlets within the planning area, including publishing an annual report that will be made available to the public. At the end of each year after the annual report is completed, the Steering Committee will hold a public meeting to discuss the progress of the hazard mitigation action strategy, highlighting any new hazards or vulnerabilities, mitigation projects underway, or grant funding opportunities that are being pursued. We will also allow public feedback and comments through a survey to see what additional information the public would like to hear about, and how this process can be improved.
StoryMap
ArcGIS StoryMaps are a story authoring web-based application for sharing maps in the context of narrative text and other multimedia content. They allow the public to interface with propertyspecific information on risk identified by a local hazard mitigation plan. A StoryMap that was constructed during the course of this plan update process will be used to support the implementation of the plan by providing the public continuing access to the plan and its maintenance process. The StoryMap will remain with the County and continue as a template to support visual and data-based communication about the hazards relevant to Yolo County.
Following the completion of the plan update process, the Story Map will be released to the public and promoted through social media and the project website. It will include risk assessment results for all relevant hazards, an interactive hazard mapping tool, and a report function to produce comprehensive hazard exposure summaries for any given property, block, or defined area. The Story Map expanded opportunities for public outreach and the ways in which members of the public could interact with hazard data as the hazard mitigation plan update was underway.
Access and Functional Needs (AFN) & Cultural Diversity Work Group Disasters affect everyone and highlight the longstanding disparities and inequities experienced by people from racial and ethnic minority groups, people with low incomes, communities with less power and access to resources, and individuals who may have a disability and/or access and 519
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functional needs. To address this gap, two work groups that were created by the Office of Emergency Services include the Access and Functional Needs Work Group and the Cultural Diversity Work group.
These work groups guide the Office of Emergency Services to help provide the highest level of service to those with a disability and/or access and functional needs, as well as move beyond the traditional definitions of accessibility planning, and engage the whole-community. These work groups review and approve plans such as the Hazard Mitigation Plan (including updates) and County Emergency Operations Plan, address gaps, and develop solutions to improve the life and safety of all residents within Yolo County. These work groups help set priorities and drive meaningful change to ensure our whole community is equitable in all phases of emergency management.
Additional organizations and partnerships are continually added to these work groups, especially as the existing organizations invite other community organizations that they have partnered and worked with. We anticipate continued and increased engagement from these work groups on hazard mitigation.
6.8 INCORPORATION INTO OTHER PLANNING MECHANISMS
As a demonstration of progress in local hazard mitigation efforts, 44 CFR 201.6(c)(4)(ii) requires plan updates to describe completed steps to incorporate the hazard mitigation plan into other planning mechanisms as appropriate.
The mitigation actions recommended in this plan will be incorporated into existing planning mechanisms and programs, such as comprehensive land-use planning processes, capital improvement planning, building code enforcement and implementation. Utilizing the local capability assessment identified in Section 4.1.3, and Section 4.2 expanding capabilities, there be will be biannual review of the HMP and discussions on how the actions identified can be incorporated into yearly budget planning to expand upon existing capabilities. At the annual budget meetings, the Yolo County Office of Emergency Services Chief or Emergency Services Coordinator will lead a discussion around recommended/potential mitigation projects, from the Steering Committee, that could be incorporated into capital improvement projects or if funds become available projects that we would like to pursue. The Steering Committee will be coordinating with planning partners, responsible agencies and organizations identified with mitigation actions. These planning partners, responsible agencies and organizations, will monitor and evaluate the progress made on the implementation of mitigation actions, as well as provide a report of how they are integrating HMP information into their planning mechanisms. This will be done annual and incorporated into the annual progress report. The Office of Emergency Services will collaborate with the Department of Community Services director, at a minimum annually or when land use development plans updates are discussed, to discuss updated HMP information to incorporate into land use development plan updates. There will also be discussions with the 520
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Department of Community Services Director and Chief Building Official about building code enforcement, implementation, and NFIP/CRS criteria that can be improved upon based on HMP information. The 2023 HMP hazards and vulnerabilities discussion also feeds into specific hazard annexes. Following adoption of the 2023 HMP, the specific hazard annexes will also be reviewed and updated.
Each participating jurisdiction will describe their process for integrating information from the HMP into their planning mechanisms in their individual jurisdictional annexes. At a minimum, HMP information will need to be incorporated into the City’s Emergency Operations Plan, General Plan, City Land Use and Development Plans, Annual Budgets, and Capital Improvement Plans. The Steering Committee will continue to provide oversight and accountability to ensure HMP information is being incorporated into jurisdictional planning mechanisms through the annual progress report surveys.
The information on hazard, risk, vulnerability, and mitigation contained in this plan is based on the best science and technology available at the time this update was prepared. The general plans of the County and the city planning partners are considered to be integral parts of this plan. The County and partner cities, through adoption of general plans and zoning ordinances, have planned for the impact of natural hazards. The hazard mitigation plan update provided the County and the cities with an opportunity to review policies contained within these planning mechanisms. The planning partners used their general plans and the hazard mitigation plan as complementary documents that work together to achieve the goal of reducing risk exposure to the community members of the Yolo County. An update to a general plan may trigger an update to the hazard mitigation plan. All municipal planning partners support the creation of a linkage between the hazard mitigation plan and their individual general plans by identifying a mitigation action as such and giving that action a high priority. Other planning processes and programs to be coordinated with the recommendations of the hazard mitigation plan may include the following:
• Yolo County General Plan
• Emergency response plans
• Yolo County Climate Action and Adaptation Plan
• Training and exercise of emergency response plans
• Debris management plans
• Drought Resiliency plans
• Recovery plans
• Capital improvement programs
• Municipal codes
• Community design guidelines
• Water-efficient landscape design guidelines
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• Stormwater management programs
• Water system vulnerability assessments
• Community wildfire protection plans
• Comprehensive flood hazard management plans
• Resiliency plans
• Community Development Block Grant Disaster Recovery action plans • Public information/education plans.
Some action items do not need to be implemented through regulation. Instead, they can be implemented through the creation of new educational programs, continued interagency coordination, or improved public participation. As information becomes available from other planning mechanisms that can enhance this plan, that information will be incorporated via the update process. The following plans and programs currently integrate components of the hazard mitigation strategy:
• Yolo County Emergency Operations Plan – The Emergency Operations Plan addresses the City’s responsibilities in emergencies associated with natural disasters, human-caused emergencies and technological incidents. It provides a framework for coordination of response and recovery efforts within the County and with local, state, and federal agencies. The plan establishes an emergency organization to direct and control operations during a period of emergency by assigning responsibilities to specific personnel.
Information from the hazard mitigation plan is incorporated as appropriate. Once the 2023 HMP Update is adopted, the Yolo County EOP will be updated based on the hazards, vulnerabilities identified. The Yolo County EOP will then go through an review and approval process and final adoption.
• City Emergency Operations Plan – Each jurisdiction’s Emergency Operations Plan will need to incorporate information from the 2023 HMP Update and specific jurisdictional annexes. To ensure these changes are made, the City Emergency Operations Plan will need to undergo reviews and approval once these updates are incorporated. • Yolo County General Plan Health and Safety Element – The Health and Safety Element in the Yolo County General Plan includes a discussion of earthquakes, flood hazards, wildfires, land subsidence. The hazard mitigation plan was adopted as an implementation appendix to the Health and Safety Element. The 2023 HMP Update will trigger an amendment to the Yolo County General Plan, Health and Safety Element, and the HMP will need to be adopted into the General Plan. This goes through a review process with the Board of Supervisors for approval to the amendment. • Yolo County Climate Action and Adaptation Plan – The County’s Climate Action and Adaptation Plan outlines actions that Yolo County will take to meet greenhouse gas emissions reductions goals and help the community become more resilient to climate impacts such as higher temperatures, more frequent wildfires, floods, and drought. These 522
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projects are reviewed monthly to identify cross-planning initiatives that serve both adaptation and mitigation objectives.
• NFIP – Community Rating System – There are several activities and elements of the HMP that could contribute to CRS rating system, such as warning and response, levee and dam mitigation measures. Yolo County Office of Emergency Services, will be collaborating with Yolo County Department of Community Services, specifically our Floodplain manager to collaborate on these efforts. In 2024 we will be undergoing a cycle verification and will have the opportunity to increase our community rating classification score.
• Care and Shelter for People with Access and Functional needs – The County addresses the needs of individuals with disabilities and the elderly during an emergency or disaster situation, and provides safe, sanitary, secure shelter and care for all residents, including those with access and functional needs. An Access and Functional needs workgroup will be formed to examine current plans, vulnerabilities identified through the 2023 HMP functional needs individuals.
This list of plans may continue to grow as new stakeholders and partners continue to get added to the HMP planning process. When additional plans integrate information from the 2023 HMP update, the process of integrating information into those additional plans will be further described in the next HMP update in 2028. With each HMP update, the Steering Committee strives to involve more participants and utilizes the HMP update as an opportunity to bring awareness to hazard mitigation, through education and awareness, and plan integration. When there are mitigation success stories either through mitigation projects or plan integration, information will be captured in annual reports and in the next HMP update. 523
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APPENDIX A:
PLANNING
DOCUMENTATION
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LETTER OF INTEREST (LOI) TEMPLATE
<Place on City/District Letterhead>
Yolo County OA Multi-Jurisdictional Hazard Mitigation Plan C/O Office of Emergency Services
625 Court St, Room 202
Woodland, CA 95695
<Date>
<NAME>
<ADDRESS LINE 1>
<ADDRESS LINE 2>
<CITY, STATE, ZIP>
Yolo County Office of Emergency Services,
Please be advised that the _________________________ (insert City or district name) is committed to participating in the update to the 2023 Yolo County Operational Area Multi-Jurisdictional Hazard Mitigation Plan (HMP). As the jurisdictional representative tasked with this planning effort, I certify that we will commit all necessary resources to meet Partnership expectations as outlined in the “Planning Partners expectations” document provided by the planning team to obtain Disaster Mitigation Act (DMA) compliance for our jurisdiction.
__________________________________ will be our jurisdiction’s point of contact for this process, and they can be reached at:
<Address>
<Preferred Phone number>
<e-mail address>
Sincerely,
<Name>
<Title>
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PLANNING PARTNER EXPECTATIONS
PLANNING PARTNER EXPECTATIONS
The federal Disaster Mitigation Act (DMA) of 2000 (Public Law 106-390), commonly known as the 2000 Stafford Act amendments, was approved by Congress on October 10, 2000. This act required state and local governments to develop hazard mitigation plans as a condition for federal grant assistance. This legislation reinforces the importance of pre-disaster infrastructure mitigation planning to reduce disaster losses nationwide. DMA 2000 is aimed primarily at controlling and streamlining federal disaster relief administration and programs to promote mitigation activities. Before 2000, federal legislation provided funding for disaster relief, recovery, and some hazard mitigation planning. The DMA improves upon the planning process by emphasizing the importance of communities planning for disasters before they occur.
The Disaster Mitigation Act defines a “local government” as:
Any county, municipality, city, town, public authority, school district, special district, intrastate district, council of governments (regardless of whether the council of governments is incorporated as a nonprofit corporation under State law), regional or interstate government entity, or agency or instrumentality of a local government; any Indian tribe or authorized tribal organization, or Alaska Native village or organization; and any rural community, unincorporated town or village, or other public entity
Any local government wishing to pursue funding afforded under FEMA Hazard Mitigation Grant Programs must have an approved hazard mitigation plan to be eligible to apply for these funds.
One of the goals of the multi-jurisdictional approach to hazard mitigation planning is to achieve compliance with the Disaster Mitigation Act (DMA) for all participating members in the planning effort. DMA compliance must be certified for each member to maintain eligibility for the benefits under the DMA. Whether the planning process generates ten individual plans or one large plan that has a chapter for each partner jurisdiction, the following items must be addressed by each planning partner to achieve DMA compliance:
Participate in the Process. It must be documented in the plan that each planning partner “participated” in the process that generated the plan. Participation can vary based on the type of planning partner (i.e., City vs. a Special-Purpose District).
However,
the level of participation must be defined, and the extent to which this level of participation has been met for each partner must be contained in the planning context.
Consistency Review. Review of existing documents pertaining to each jurisdiction to identify policies or recommendations that are not consistent with those documents reviewed in producing the “parent” plan or have policies and recommendations that complement the hazard mitigation initiatives selected (i.e., comp plans, basin plans, or hazard-specific plans).
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Action Review. For plan updates, review the strategies from your prior action plan to determine those that have been accomplished and how they were accomplished; and why those that have not been accomplished were not completed.
Update Localized Risk Assessment. Personalize the Risk Assessment for each
jurisdiction by removing any hazards not associated with the defined jurisdictional area
(e.g. tsunami and coastal erosion hazards for inland jurisdictions) or redefining
vulnerability based on a hazard’s impact to a jurisdiction. This phase will include:
• A ranking of the risk
• A description of the number and type of structures at risk • An estimate of the potential dollar losses to vulnerable structures • A general description of land uses and development trends within the community so mitigation options can be considered in future land use decisions.
Capability Assessment. Each planning partner must identify and review their individual regulatory, technical, and financial capabilities regarding implementing hazard mitigation actions.
Prioritize Mitigation Recommendations. Identify and prioritize mitigation recommendations specific to each jurisdiction’s defined area.
Create an Action
Plan.
Incorporate Public Participation. Each jurisdiction must present the Plan to the public for comment at least once within two weeks before adoption.
Plan Adoption. Each jurisdiction must adopt the updated plan following FEMA
approval
.
One of the benefits of multi-jurisdictional planning is the ability to pool resources. This means more than monetary resources. Resources such as staff time, meeting locations, media resources, and technical expertise will all need to be utilized to generate a successful plan. In addition, these resources can be pooled so that a peer group can make decisions that apply to the whole and thus reduce each planning partner's individual level of effort. The formation of a steering committee will accomplish this made up of planning partners and other “stakeholders” within the planning area. The planning partnership will determine the size and makeup of this steering committee. This body will assume the decision-making responsibilities on behalf of the entire partnership. This will streamline the planning process by reducing the number of meetings that will need to be attended by each planning partner. The assembled Steering Committee for this effort will meet monthly on an as-needed basis as determined by the 527
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planning team. It will provide guidance and decision-making during all phases of the plan’s development.
With the above participation requirements in mind, each partner is expected to aid this process by being prepared to develop its section of the plan. To be an eligible planning partner in this effort, each planning partner shall provide the following:
A. Submit a Letter of Intent (LOI) to participate; you must submit an LOI.
B. Designate a lead and alternate points of contact for this effort. The lead will be listed as the plan's hazard mitigation point of contact for your
city/jurisdiction.
C. If requested, provide support in the form of a mailing list and public information materials, such as newsletters, newspapers, or direct mailed brochures, required to implement the public engagement strategy developed by the Steering Committee.
D. Participate in the entire process (from the first partner meeting to plan completion).
There will be many ways this plan involves participating. Opportunities such as:
a. Attending in-person/online Steering Committee meetings b. Attending in-person/online public meetings
c. Completing the phased Jurisdiction Annex Process
d. Participating in public review and comment periods before adoption At each of these meetings, attendance will be recorded. Attendance records will be used to document participation for each planning partner. No thresholds will be established as minimum levels of participation. However, each planning partner should attempt to attend all possible meetings and events.
E. Designate a Local Planning Team. Each planning partner will be asked to identify a lead point of contact and an alternate point of contact for their jurisdiction as well as other resources within that jurisdiction that can support or enhance the mitigation actions from this plan. For municipal planning partners, participants should include, at a minimum, representation from Planning, Public Works, and Emergency Management. For Special Purpose Districts, participants should include those responsible for facilities and/or emergency management. All phases of the Jurisdictional Annex process should be conducted through these local planning teams.
F. Complete all 3 phases of the Jurisdictional Annex process. Volume 2 of the plan consists of jurisdictional specific components of the plan required under section 2016, 44CFR for multi-jurisdictional local hazard mitigation plans. It is mission-critical to the ultimate approval of this plan update that these annexes are created or updated in accordance with the requirements. To achieve this compliance, the Core Planning Team (CPT) will deploy the Jurisdictional Annex process in the following 3 phases over the course of this plan update process:
• Phase 1 - Jurisdiction Profiles and Prior Action Review • Phase 2 - Core Capability Assessment
• Phase 3 - Risk Ranking and Action Plan Development
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Complete and thorough technical assistance will be available to all planning partners during this phased process.
Failure to meet deadlines specified for Phases 1 and 2 will not jeopardize and planning partner’s eligibility for coverage under the plan. However, it is important to note that if a planning partner does not meet the deadline for Phase 1, it is expected that the information submitted during Phase 2 will include all of the information requested under Phases 1 and 2. The ultimate deadline for this phased process will be the deadline for Phase 3.
Failure to submit a complete Jurisdictional Annex by the specified deadline for Phase 3 will result in a planning partner’s removal from the Partnership for failure to meet the specified planning partner expectations.
Phase 3 will include a mandatory workshop focusing on action plan development and prioritization. Attendance at the Phase 3 workshop will be tracked, and each planning partner must send at least one representative to the workshop to fully meet the participation requirements defined for this plan update process.
At a minimum, two workshops will be conducted - one for municipal planning partners and one for special district planning partners to guide action plan development specific to the differing capabilities between these two planning partner types.
G. Each partner will be asked to perform a “consistency review” of all technical studies, plans, and ordinances specific to hazards to determine the existence of any not consistent with the same documents reviewed in the preparation of the County (parent) Plan. For example, suppose your community has a floodplain management plan that makes recommendations inconsistent with any of the County’s Plans. In that case, that plan will need to be reviewed for probable incorporation into the plan for your area.
H. Each partner will be asked to review the Risk Assessment and identify hazards and vulnerabilities specific to its jurisdiction. Contract resources will provide jurisdiction - specific mapping and technical consultation to aid in this task, but the determination of risk and vulnerability will be up to each partner.
I. Each partner will be asked to review and determine if the mitigation recommendations chosen in the parent plan will meet the needs of its jurisdiction.
Projects within each jurisdiction consistent with the parent plan recommendations will need to be identified, prioritized, and reviewed to determine their benefits vs. costs.
J. Each partner will be required to create its own action plan that identifies each project, who will oversee the task, how it will be financed, and when it is estimated to occur.
K. Each partner will be required to adopt the plan formally. 529
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Templates and instructions to aid in compiling this information will be provided to all committed planning partners. Each partner will be asked to complete their templates on time and according to the timeline specified.
NOTE: Once this plan is completed and DMA compliance has been determined for each partner, maintaining that eligibility will depend upon each partner implementing the plan implementation- maintenance protocol identified in the plan. 530
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2018 INITIAL HMP MEETINGS
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2018 FIRST PUBLIC MEETING
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2018 STEERING COMMITTEE MEETING
2019 PLANNING MEETINGS
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2019 STEERING COMMITTEE MEETINGS
2023 KICKOFF PLANNING MEETINGS
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2023 PLANNING MEETING
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Regional and Neighboring County Meeting
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Public Meetings
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Sample Risk Assessment Worksheet
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APPENDIX B: OLD
MITIGATION PROJECT
LIST
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MITIGATION PROJECTS
Mitigation Project
Jurisdiction/
Responsible
Agency
New/ Existing
or
Completed/
Deleted
Estimated
Cost and
Potential
Funding
Source
Timeframe
of
Completion
Comments/
Progress
ALL HAZARDS
Completed or Deleted Items
Community Warning
System
All / Yolo
County OES
COMPLETED
(2005)
Yolo County
OES General
Fund
Completed
These systems are
continually
updated due to
changing
technology
Emergency Generator –
District Office
Yolo County
/ RD108
COMPLETED
(2017)
$70,000
PDM, HMGP 2020 Completed
Develop Public Health and
Mass Care Tiered Response
System Countywide
All / Yolo
County
HHSA
DELETED
(2013) DELETED Deleted
Major advance in
capability within
medical and
human services
communities to
meet needs of
Yolo County
residents
2018 Yolo County Hazard
Mitigation Plan Update
All / Yolo
County OES
COMPLETED
(2016) PDM, HMGP 2018 Five-year required update
FLOODING/LEVEE FAILURE
Completed/Deleted Items
Flood Response Planning
Project to Include GIS
Mapping
Yolo County
/ Yolo
County OES,
West
Sacramento /
Public
Works
Department
Completed
(2013) DWR Grants Completed Completed
West Adams Canal Road
and Cache Creek Bank
Erosion Emergency Repair
Project
Yolo
County/
YCFCWCD
COMPLETED
(2017)
$250,000
CDAA/FEMA
Funding and
YCFCWCD
Capital Job
Funding
June 2017 Completed
Invasive Species Removal in
Canals
Yolo County
/ RD108 DELETED DELETED DELETED DELETED
CLIMATE CHANGE
Completed/Deleted Items
Farmer Outreach
Program to
Reduce Fossil
Fuel Consumption
Yolo County /
Department of
Agriculture
DELETED DELETED DELETED
New initiatives
being handled by
Sustainability
group
584
2023 Yolo Multi-Jurisdictional
Hazard Mitigation Plan Update December 2023
402
Appendix B: Mitigation Project List Yolo Operational Area
Farmer Outreach
Program to
Reduce
Greenhouse Gas
Emissions
Yolo County /
Department of
Agriculture
DELETED DELETED DELETED
New initiatives
being handled by
Sustainability
group
Program to
Reduce Energy
Use in
Agricultural
Pumping
Yolo County /
Department of
Agriculture,
Community
Services
Department
DELETED DELETED DELETED
New initiatives
being handled by
Sustainability
group
Program to
Reduce Livestock
Manure Methane
Emissions
Yolo County /
Department of
Agriculture
DELETED DELETED DELETED
New initiatives
being handled by
Sustainability
group
Program to
Reduce Methyl
Bromide
Application
Yolo County /
Department of
Agriculture,
Community
Services
Department
DELETED DELETED DELETED
New initiatives
being handled by
Sustainability
group
Program to
Sequester Carbon
in Agricultural
Landscapes
Yolo County /
Department of
Agriculture,
Community
Services
Department
DELETED DELETED DELETED
New initiatives
being handled by
Sustainability
group
Program to
Reduce Vehicle
Miles Traveled
Yolo County/
Community
Services
Department
DELETED DELETED DELETED
New initiatives
being handled by
Sustainability
group
Community
Choice
Aggregation
(CCA) Program
Yolo County /
County
Administrator
Office
DELETED DELETED DELETED
New initiatives
being handled by
Sustainability
group
Program to
Reduce Energy
Consumption in
Existing
Residential and
Non-Residential
Units
Yolo County /
Community
Services
Department
DELETED DELETED DELETED
New initiatives
being handled by
Sustainability
group
Program to
Reduce Energy
Consumption in
New Residential
and NonResidential Units
Yolo County /
Community
Services
Department
DELETED DELETED DELETED
New initiatives
being handled by
Sustainability
group
585
2023 Yolo Multi-Jurisdictional
Hazard Mitigation Plan Update December 2023
403
Appendix B: Mitigation Project List Yolo Operational Area
Program to
Increase On-Site
Renewable
Energy
Generation to
Reduce Demand
for Grid Energy
Yolo County /
Community
Services
Department
DELETED DELETED DELETED
New initiatives
being handled by
Sustainability
group
Program to
Promote On-Farm
Renewable
Energy Facilities
Yolo County /
Community
Services
Department
DELETED DELETED DELETED
New initiatives
being handled by
Sustainability
group
Program to
Reduce Water
Consumption in
Existing Buildings
through Increased
Plumbing Fixture
Efficiency
Yolo County /
Community
Services
Department
DELETED DELETED DELETED
New initiatives
being handled by
Sustainability
group
Program to
Promote WeatherBased Irrigation
Systems and
Water Efficient
Turf Management
Yolo County /
Community
Services
Department
DELETED DELETED DELETED
New initiatives
being handled by
Sustainability
group
Program to
Expand Landfill
Methane Capture
Systems
Yolo County /
Community
Services
Department
DELETED DELETED DELETED
New initiatives
being handled by
Sustainability
group
Program to
Prepare for the
Effects of Climate
Change on
Agriculture
Yolo County /
Community
Services
Department
DELETED DELETED DELETED
New initiatives
being handled by
Sustainability
group
Program to
Prepare for
Climate Change
Effects on Water
Resources
Yolo County /
County
Administrator
Office,
Community
Services
Department
DELETED DELETED DELETED
New initiatives
being handled by
Sustainability
group
Program to
Respond to the
Potential Threat of
Sea-Level Rise
Yolo County /
Office of
Emergency
Services /
Community
Services
Department
DELETED DELETED DELETED
New initiatives
being handled by
Sustainability
group
Program to Protect
the Public from
Increased Health
Risks
Yolo County /
OES, HHSA DELETED DELETED DELETED
New initiatives
being handled by
Sustainability
group
586
2023 Yolo Multi-Jurisdictional
Hazard Mitigation Plan Update December 2023
404
Appendix B: Mitigation Project List Yolo Operational Area
Program to
Develop
Governance
Strategies to
Ensure that Yolo
County Remains
Resilient to
Climate Change
Yolo County/
OES, Community
Services
Department
DELETED DELETED DELETED
New initiatives
being handled by
Sustainability
group
587
2023 Yolo Multi-Jurisdictional
Hazard Mitigation Plan Update December 2023
405
Appendix C: Adoption Letters Yolo Operational Area
APPENDIX C:
ADOPTION LETTERS
588
2023 Yolo Multi-Jurisdictional
Hazard Mitigation Plan Update December 2023
406
Appendix C: Adoption Letters Yolo Operational Area
589
2023 Yolo Multi-Jurisdictional
Hazard Mitigation Plan Update December 2023
407
Appendix D: Adoption Letters Yolo Operational Area
This document is a support annex to local
Emergency Operations Plans
2023
YOLO COUNTY
OPERATIONAL
AREA
MJHMP
VOLUME 2:
JURISDICTIONAL
ANNEXES
December 2023
590
2023 Yolo Multi-Jurisdictional
Hazard Mitigation Plan Update December 2023
408
Section 7.0: Plan Review, Evaluation & Implementation 591 Yocha Dehe Wintun Nation 2023 Yolo Multi-Jurisdictional
Hazard Mitigation Plan Update December 2023
409
Section 7.0: Plan Review, Evaluation & Implementation 592 Yocha Dehe Wintun Nation
CITY COUNCIL AGENDA REPORT
MEETING DATE: April 9, 2025 ITEM # 11
SUBJECT:
CONSIDERATION OF RESOLUTION 25-35 DECLARING WEEDS GROWING ON
CERTAIN LOTS TO BE A PUBLIC NUISANCE AND SCHEDULING A PUBLIC
HEARING TO CONSIDER OBJECTIONS TO WEED ABATEMENT
INITIATED OR REQUESTED BY: REPORT COORDINATED OR PREPARED BY:
[ ] Council [X] Staff
[ ] Other
Bryan Jonson, Fire Marshal
Fire Department
ATTACHMENT [X] Yes [ ] No [ ] Information [ ] Direction [X] Action
OBJECTIVE
The purpose of this report is to initiate the 2025 Weed Abatement Program which is a proactive approach to reducing the risk of vegetation fires. This item requests City Council adoption of a resolution declaring a list of lots to be hazards and set a public hearing at the April 30, 2025, City Council meeting to consider objections to the proposed removal of weeds. The program provides for weed abatement by the City’s contractor to commence on May 10, 2025.
RECOMMENDED ACTION
Staff respectfully recommends that the City Council:
1. Adopt Resolution 25-35 declaring weeds growing on certain lots to be a public nuisance and initiating the 2024 weed abatement program. The Resolution further directs the Fire Department to begin the formal weed abatement process by notifying all affected property owners by mail of the intended action by April 10, 2024; and
2. Set a public hearing at its regular meeting of April 30, 2024, to consider objections to the proposed removal of weeds.
BACKGROUND
This will be the 38th year the City has conducted weed abatement on non-complying properties. Each year the program has been highly successful in reducing the total number of vegetation fires, intensity and size of vegetation fires, and citizen complaints regarding high vegetation.
This year the program provides for weed abatement by the contractor to commence on May 10, 2025. The total annual contract has historically been under $30,000 with 100% recovery of the contract costs for private party weed abatement plus a 20% City of West Sacramento administrative fee. Property owners are given one opportunity to pay for the services provided by the City contractor and if they do not, a lien will be placed on the property.
ANALYSIS
Combustible vegetation and wildland/urban interface (WUI) fires have often been in the news in recent years.
Twelve of the 25 costliest (in terms of property loss) fires in U.S. history were described as forest, wildland or Wildland Urban Interface (WUI) fires, with the seven costliest in the last two decades. Although West Sacramento does not have specifically defined WUI in our jurisdiction, we do have exposure to vegetation fires with the vast of undeveloped land in the southern part of the city.
Based on data from the most current (2018) National Fire Protection Association’s (NFPA’s) report, Brush, Grass, and Forest Fires, local fire departments responded to an estimated average of 306,000 brush, grass, and forest (vegetation) fires in the U.S. per year in 2011-2015, an average of 840 per day. These incidents accounted for almost one quarter (23%) of the fires reported to local fire departments during this period. That coupled with California representing the second highest percentage (12%) of total vegetated acres burned (332,722) in the U.S. in 2023, the City’s weed abatement program is our way to keep these types of fires and statistics low in West Sacramento.
A proactive approach to reducing the risk of vegetation fires in the upcoming months will aid in the reduction of fire threat and property damage. By the authority dictated by the California Government Code Sections 39560– 39588, the City has created the Weed Abatement Program to ensure that this unnecessary fire threat is managed. Pursuant to this authority, Staff is requesting Council approval of Resolution 25-35 declaring weeds growing on certain lots to be a public nuisance, initiating the 2025 weed abatement program and directing the 593
Consideration of Resolution 25-35
April 9, 2025