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FIGURE 2 EXAMPLE OF CASCADING EFFECTS
Drought conditions occur, landscapes become more flammable
Wildfires spread faster with drier/more droughttolerant fuels
Wildfires modify supportive vegetation on hillsides
Increase susceptibility to landslides due to vegetation changes that destabilize slope
The climate change hazard data was derived from best available downscaled data, including the state Cal-Adapt database, the APG, the California Fourth Climate Change Assessment, and the Contra Costa County Local Hazard Mitigation Plan (adopted in 2018)
Step 2. Identify Sensitivities and Potential Impacts. The second step of the Vulnerability Assessment involved evaluating potential future climate change impacts to community populations and assets. City staff first identified a comprehensive list of populations and assets to understand how susceptible different people, places, ecosystem services, and community services are affected by climate change hazards. This list includes 18 building and infrastructure types, 5 economic drivers, 5 ecosystems and natural resources, and 8 key services, as shown in Table 1 and described in more detail in Appendix A
Sensitivity: The level to which a species, natural system, or community, government, etc., would be affected by changing climate conditions.
Impact: The effects (especially the negative effects) of a hazard or other conditions associated with climate change.
Source: California Adaptation Planning Guide
Category
Populations
Table 1 List Of Populations And Assets
Children (under 10)
Cost-burdened households
Households in poverty
Immigrant communities
Linguistically isolated persons
Low-income households
Bicycling and pedestrian trails
Bridges
Communication facilities
Buildings and Infrastructure
Populations or Assets
Low-resourced people of color
Persons without access to lifelines
Outdoor workers Renters
Overcrowded households
Persons experiencing homelessness
Persons with chronic illness and/or disabilities
Persons without a high school degree
Flood control and stormwater infrastructure
Government administration facilities
Hazardous materials sites
Community centers
Electrical transmission infrastructure
Cooling centers
Education
Economic Drivers
Ecosystems and Natural Resources
Key Services
Finance and insurance
Oak woodlands
Homes and residential structures
Libraries
Major roads and highways
Healthcare and social assistance
Major employers
Riparian
Grassland Scrub
Communication services
Emergency medical response
Energy delivery
Government administration and community services
Public safety response
Public transit access
Seniors (65+)
Seniors living alone
Unemployed persons
Natural gas pipelines
Parks and open space
Public safety buildings
Schools
Transit facilities
Water and wastewater infrastructure
Professional, scientific, and technical services
Wetlands and vernal pools
Solid waste removal
Water and wastewater
The evaluation of these populations and assets allowed City staff to prioritize vulnerabilities across several sectors to build resiliency for the most susceptible people and assets in the city. Some assets, such as state and regional parks, are outside the city limits but serve residents of Orinda as employment or recreation centers, and therefore were included in the assessment. Following confirmation of this list, City staff developed an applicability matrix, which looked at which hazards are likely to affect which populations and assets. For example, human health hazards are likely to affect most populations, but they would not physically affect buildings.
After the applicability review, City staff evaluated potential impacts to the applicable populatio ns and community assets. To identify how severe the impacts of each relevant hazard are on the populations and community assets, City staff considered several different questions that helped ensure the assessment broadly covered a range of potential harm, including:
• What types of potential impacts may occur?
• What is the risk of harm, including physical injury or damage, behavioral or mental harm, or loss of economic activity?
• How many people or assets may be affected?
• How soon would impacts happen and how long would they persist?
• Is there a substantial risk of death or widespread destruction?
Based on the results of the impact assessment, the City ranked each population and asset as experiencing low, medium, or high impacts for each relevant hazard. Impact is considered a negative quality, and therefore, a higher impact score means that there is a higher potential for harm to a population or asset, while a lower impact score means that there is a lower potential for harm to a population or asset.
Step 3. Assess Adaptive Capacity. As the third step of the Vulnerability Assessment, City staff evaluated each population and asset’s adaptive capacity by considering a series of questions, including:
• Are there existing programs, policies, funding, or other efforts to provide assistance, reverse or repair damage, or restore or adapt resources or assets?
• Are there existing barriers that limit response or recovery? Are these financial limitations, political challenges, lack of access to technology, or others?
• Are there alternatives in or near Orinda that community members can use? Are there redundant resources that the community can rely on in case of failure or loss of function of primary resources?
Adaptive Capacity: The “combination of the strengths, attributes, and resources available to an individual, community, society, or organization that can be used to prepare for and undertake actions to reduce adverse impacts, moderate harm, or exploit beneficial opportunities.”
Source: California Adaptation Planning Guide
Based on the results of the adaptive capacity assessment, the City ranked the adaptive capacity of each population or asset as low, medium, or high for each relevant hazard. Adaptive capacity is considered a positive attribute, so a higher adaptive capacity score will mean that a population or asset may be more adaptable to the hazard. A lower adaptive capacity score means that a population or asset may have a harder time adjusting to the changing conditions given available resources.
Step 4. Prioritize Vulnerability Scoring. To complete the Vulnerability Assessment, the City used the impact and adaptive capacity scores for each population and asset for each relevant hazard to determine a vulnerability score. The vulnerability score reflects how susceptible a population or asset is to harm from a particular hazard. Vulnerability is assessed on a scale of low, medium, and high. Low vulnerability does not mean that the population or asset will be unaffected by climate change, but that the effects are likely to be less substantial.
Vulnerability: The degree to which natural, built, and human systems are susceptible “…to harm from exposure to stresses associated with environmental and social change and from the absence of capacity to adapt.”
Source: California Adaptation Planning Guide
The matrix in Figure 3 shows how impact and adaptive capacity scores combine and translate into a vulnerability score. For example, extreme heat is expected to create a high impact on energy delivery services as mechanical failures, heat damage, and high demand for electricity from cooling equipment can disrupt this service. Adaptive capacity is expected to be low because many community members need to use more electricity on extreme heat days to keep cool and retrofitting electrical equipment can be expensive. Therefore, energy delivery services would have a vulnerability score of V5 to extreme heat.
3.2 Climate Change Hazards and Key Vulnerabilities
The Vulnerability Assessment assigns vulnerability scores to 282 unique pairings of 53 populations and assets for each of the relevant 7 hazards. This section describes the climate change hazards projected to occur at the local level and discusses the significant vulnerabilities created by those hazards.
• Low-resourced people of color, seniors living alone, households in poverty, and persons with chronic illnesses and/or disabilities are the most vulnerable to climate change hazards. Persons who are unable to drive, lack access to reliable transportation, or are in areas with limited roadway access are particularly susceptible.
• Power lines are among the most vulnerable structures, as they connect to Orinda by passing through areas of very high wildfire risk, elevated landslide risks, and locations subject to severe weather and high winds. Other vulnerable buildings and infrastructure include major roads and highways and homes and residential structures.
• Riparian habitat and wetlands and vernal pools are the most vulnerable ecosystems and natural resources. Such ecosystems are already limited and threatened by other environmental factors, making them particularly susceptible to climate change
• Energy delivery, public transit access, and water and wastewater treatment are the most vulnerable key services.
For a complete list of vulnerability scores, see Appendix B.
Drought
A drought occurs when conditions are drier than normal for an extended period, making less water available for people and ecosystems. Droughts are a regular occurrence in California; however, scientists expect that climate change will lead to more frequent and more intense droughts statewide. As of March 2022, Orinda and the greater Contra County region, and State of California are in severe drought conditions. 8 Overall, precipitation events are expected to become less frequent and more intense, which in turn may lead to more frequent and intense drought periods. In an earlycentury drought (2023 to 2042), the City could experience a drop in average precipitation from an average of 30.4 inches per year to an average of 26.2 inches per year. 9 In a late-century drought (2051 to 2070), precipitation could also drop to an average of 26.2 inches per year. 10 As described below, average temperatures and average number of extreme heat days are both projected to increase in Orinda over the course of this century, which may also facilitate drought conditions.
Orinda’s water supply comes from the East Bay Municipal Utility District (EBMUD) and is delivered by the Orinda Water Treatment Plant. EBMUD’s water supply begins at the Mokelumne River watershed in the Sierra Nevada and extends 90 miles to the East Bay, passing through the Sacramento-San Joaquin Delta. Snowmelt in the Sierra Nevada accounts for approximately 90 percent of EBMUD’s drinking water supply, with other sources, such as local supplies and the Sacramento River, accounting for the remaining supplies.
Snowpack levels in the Sierra Nevada dropped by 25 percent during the 2011 to 2016 drought, and average springtime snowpack is expected to drop by up to 64 percent by 2100. 11 In April 2022, the California Department of Water Resources noted that statewide snowpack is only 38 percent of normal. 12 During drought conditions, water stored in Pardee Reservoir could decrease due to lack of rainfall and reduction in snowpack because of higher temperatures, causing water shortages during extended drought conditions or price hikes that could increase economic instability of low-income and low-resourced residents.
EBMUD does have plans in place that include increased water conservation programs, sourcing water from other sources, and other contingency efforts. While such plans help provide increased resilience to drought conditions, there remains some possibility of disruption to the local water supplies. Increases in recycled water supplies are an option, although at present they cannot replace local potable water needs. Despite the high level of median household income in Orinda, some lower- income households and businesses may be challenged to upgrade fixtures and appliances to waterefficient versions. Fines for excess water use can also have a disproportionate effect on lower-income persons.
Orinda’s habitats most vulnerable to drought are chaparral, riparian, and wetland habitats, which depend on water from rainfall and groundwater. In chaparral ecosystems, drought can weaken plant and tree species, causing habitat dieback or conversion to grassland or other vegetation types that may be more suited to less rainfall. 13 Drought conditions can also dry out vegetation and increase wildfire conditions, which could put a strain on firefighting equipment and personnel, in addition to the threat of injury, loss of life, or property damage or destruction. Trees may not receive adequate water during drought periods, which can lead to pests and diseases destroying important habitat and can make trees more vulnerable to wildfire.
Drought conditions can cause smaller streams to run dry, which can subsequently harm the plants and animal habitat within riverine and aquatic ecosystems. Soil erosion can also occur on the banks of streams 14 Wetlands can be directly affected by reduced water quantity and quality due to drought conditions. Drought can contribute to algal blooms, low streamflow, degraded water quality, higher temperatures, and increased erosion in both Delta and inland wetland habitats.
Extreme Heat and Warm Nights
Extreme heat occurs when temperatures rise significantly above normal levels. In Orinda, an extreme heat day occurs when temperatures reach above 91.4°F. As shown in Figure 4, the number of extreme heat days in Orinda is projected to increase from an average of 4 days historically, to an average of 15 extreme heat days per year by mid-century (2035 to 2064), and an average of 27 by the end of the century (2070 to 2099). 15
Sources: Cal-Adapt, 2022; National Weather Service, 2022.
Extreme heat can also occur in the form of warmer nights, as temperatures do not cool down overnight and provide relief from the heat. In Orinda, a warm night occurs when the temperature stays above 58.3°F. As shown in Figure 5, the number of warm nights in Orinda is projected to increase from an average of 6 historically to an average of 53 warm nights per year by mid-century, and an average of 117 warm nights per year by the end of the century.
Figure 5 Projected Warm Nights In Orinda
Note that the visual change in Figures 4 and 5 from 2020 to 2021 is due to a need to use multiple sources for the observed data. The data from 1950 to 2005 and 2020 to 2100 are derived from CalAdapt. The data from 2006 to 2020 are from the National Weather Service. Therefore, the observed extreme heat days and warm nights differ slightly from the projections. In recent years, the observations exceed what the average projections are showing.
Extreme heat can cause heat-related illnesses, such as heat cramps, heat exhaustion, and heat stroke, in addition to worsening respiratory and cardiovascular conditions. The most vulnerable populations are those that spend a disproportionately high amount of time outside, such as children, outdoor workers, immigrant communities, and persons experiencing homelessness. Additionally, persons with chronic illnesses, populations with existing pollution burdens, and senior citizens are highly vulnerable to extreme heat due to potential existing health conditions. Persons with financial instability, or who are low-resourced are also highly vulnerable due to a lack of financial resources to prepare for or respond to extreme heat conditions.
Some homes in Orinda may lack air conditioning or effective insulation, and as a result, people living in these homes may be more susceptible to harm from extreme heat events. Approximately 83 percent of Orinda’s housing units were built prior to 1980, before the establishment of modern building codes. 16 The City has one designated cooling center at the Orinda Public Library , although this facility is not always open when it is needed. Residents may not be able to cool homes or keep medications cooled if extreme heat events cause rolling blackouts. When extreme heat is combined with severe fire weather and high winds, electricity may be turned off through Public Safety Power
Shutoff (PSPS) events, and residents may not be able to cool their homes during extreme heat days. Rolling blackouts may also cause food loss due to lack of refrigeration when the power is turned off, which could harm persons with financial instability or limited income.
Energy delivery services, and associated infrastructure, are highly vulnerable to extreme heat, as high temperatures can stress and overload the regional grid, causing power outages and damage to the transmission lines. Transportation infrastructure, such as evacuation routes, major roadways and highways, and railways, are also highly vulnerable to extreme heat and prolonged periods of high temperatures, which can crack, heave, or deform roadway and railway materials, damaging major roads, transit corridors, and evacuation routes or making them difficult to drive or travel on. 17
Additional vulnerabilities include the following:
• Outdoor recreation, as people may be deterred from recreating outdoors in high temperatures.
• Wetlands and vernal pools habitat, which can alter species composition and cause harmful algal growth that can harm both plant and wildlife species as temperatures increase.
• Scrub habitat, which can experience species composition shifts with higher average temperatures.
• Public transit access, as extreme heat reduces ridership of County Connection and BART since it may be more difficult to wait outside for the bus or train.
Flooding
Inland flooding can cause significant harm to buildings, people, and infrastructure. Floodwater can be deep enough to drown people and may move fast enough to carry people or heavy objects (such as cars) away. Flooding can be caused by heavy rainfall, long periods of moderate rainfall, or clogged drains during periods of light rainfall. In rare instances, a break in a dam holding back water in a reservoir, such as Briones Reservoir or Lake Cascade could cause devastating flooding. Storm drainage systems throughout the city collect stormwater runoff and convey water to prevent flooding, although these systems are typically designed based on winter storms recorded in the past and may not be designed to accommodate more intense storms.
Floods are expected to occur more frequently as a result of climate change, affecting what the community understands as a “normal” flood. For example, what is currently considered a 100-year flood, or a flood that has a 1-percent chance of occurring annually, may occur every 20 or 50 years. Figure 6 shows that the flood hazard areas are primarily along San Pablo Creek, Lauterwasser Creek, as well as other low-lying areas in the southeastern portion of the city.
The Federal Emergency Management Agency (FEMA) defines a 100-year floodplain as an area with a one in 100-year chance, or 1 percent, annual chance of flooding in any given year and a 500-year floodplain as an area with a one in 500-year, or 0.2 percent, annual chance of flooding in any given year.
Several populations and assets face particularly high risks from flooding events.
• Persons experiencing homelessness, households in poverty, immigrant communities, lowincome households, and low-resourced people of color are severely vulnerable to flooding, as they may live in or near flood hazard areas, lack financial resources to protect their homes, or be ineligible for grant funding to recover from flood damage to their homes.
• Persons with limited mobility and those without access to lifelines (persons without access to a car, transit, or communication systems) may have difficulty evacuating prior to a flooding event, and therefore are also highly vulnerable.
• Outdoor workers may be unable to travel to work during flooding events and worksites may be inundated by floodwaters, reducing employment opportunities.
• Transportation infrastructure, including major roads, highways, bridges, railways, evacuation routes, and transit facilities, can be inundated, blocked, and damaged by floodwaters along the San Pablo Creek.
• Employees may be unable to travel to work due to inundation of transportation infrastructure, disrupting economic drivers, public transit access, major employers, public safety response, and other services.
• Heavy rainfall and subsequent flooding can disrupt water and wastewater services, causing the water and wastewater treatment plants to not function properly. This can also cause effluent to flow into the surrounding water and soil and can reduce recycled water supplies for irrigation.
• Energy delivery systems and associated infrastructure could be damaged by floodwaters, disrupting service for hours or days depending on the severity.
• Flooding may also inundate areas with higher soil or groundwater pollution burdens, causing toxic chemicals and contaminants to spread into the water and soil. 18
• Flood-control infrastructure may fail if floodwaters exceed the capacity of the infrastructure.
• Homes and residential structures can be damaged, destroyed, or have mold and mildew growth from standing water after flooding.
• Commercial and municipal buildings could become unusable if damaged by flooding
Human Health Hazards
Human health hazards are bacteria, viruses, parasites, and other organisms that can cause diseases and illness in people. Some of these diseases may only cause a mild inconvenience, but others are potentially life threatening. Animals such as mice and rats, ticks, and mosquitos can and often carry these diseases. Warmer temperatures and high levels of precipitation can lead to increased populations of disease-carrying animals, creating a greater risk of disease and increased rates of infection. Other human health hazards can include poor air quality, which can affect respiratory systems of those exposed for prolonged periods.
Populations most vulnerable to human health hazards are those who spend a disproportionate amount of time outdoors (such as persons experiencing homelessness), those with fragile immune systems or existing illnesses (which may include persons with chronic illnesses, seniors, and pollutionburdened populations), and those who may live in sub-standard housing or not have access to health insurance and medical care (households in poverty, low-resourced people of color, immigrant communities, and overcrowded households). These persons may be living in conditions that increase their chances of catching vector-borne illnesses or lack the ability to fight off infections that may occur. Many populations may also not have access to air purification systems that can filter out harmful pathogens. 19
Major employers, such as the Orinda Union School District or the Orinda County Club, could see a decline in staff attendance and patrons due to human health hazard exposure or concerns. A reduction in workers could harm local businesses or economic drivers such as healthcare and education. This was the case in 2020 and 2021, when Contra Costa County implemented school and non-essential business closures due to the COVID-19 pandemic. Emergency medical response services are also highly vulnerable to human health hazards, as they may not be able to provide adequate services if there is an influx of health-related emergencies.
Landslides
Landslides occur when a hillside becomes unstable, causing soil and rocks to slide downslope. Landslides can include rock falls, deep failures of slopes, and shallow debris flows. 20 Landslides are most common on steep slopes and hillsides made up of loose soil or other material where excavation and grading, drainage alterations, or changes in vegetation have occurred. The Vulnerability Assessment looks at landslides that are caused by precipitation, although earthquakes can also trigger landslides. Hillsides commonly absorb water, which increases instability of the slope and may increase the risk of slope failure. Steep slopes made up of loose or fractured material are more likely to slide. In some cases, the hillsides can become so saturated that slope failures can result in a mudslide and debris flows (a mixture of soil and water moving downslope). As shown in Figure 7, a majority of the city is in a high or very high landslide susceptibility area.
Landslides and mudslides can move fast enough to damage or destroy homes or other structures in their path, block roadways, and injure or kill people caught in them. The most vulnerable populations are those that may be unable to evacuate due to limited mobility, lack of access to a vehicle or communication, or low-resourced populations that may prevent awareness and response to emergency notifications. Infrastructure, such as electrical transmission lines and water or wastewater infrastructure, can break or malfunction if the soil supporting them fails. This can lead to disruptions in energy delivery and water or wastewater services. Major transportation infrastructure, such as roadways, bridges, and evacuation routes, can be blocked or damaged by landslides preventing public transit access locally and regionally. Many homes and residential structures are in landslide-prone areas, which can be damaged or destroyed by landslides and debris flows.
Severe Weather
Severe weather is generally any destructive weather event, but usually occurs in Orinda as localized storms that bring heavy rain, hail, lightning, and strong winds. Severe weather is usually caused by intense storm systems, although types of strong winds can occur without a storm. The connection between climate change and severe weather is not as well established as other hazards, but new evidence suggests that these forms of severe weather may occur more often than in the past. 21
Heavy rainfall can cause flash floods and ponding in low-lying areas of the city. The greatest risk from flash floods is occurrence with little to no warning. Localized flooding also occurs in Orinda at various times throughout the year, especially along San Pablo Creek. Hail and lightning can damage the buildings and infrastructure supporting economic sectors and key services within the city.
Severe winds, such as the Diablo winds, tend to be most frequent during the fall and spring and can have average speeds of 40 miles per hour. Diablo winds come from the north and northeast, carrying extremely dry air at a high velocity. These winds can destroy buildings, knock over trees, damage power lines and electrical equipment, and fan small sparks into large wildfires in the region. High winds, particularly in combination with hot and dry conditions, can also cause PG&E to enact a Public Safety Power Shutoff (PSPS) event to prevent sparking of power lines. During these events, residents and businesses may lose power for hours or days depending on the severity. During power outages, businesses may be forced to close, causing economic harm. Residents can lose access to communication, suffer economic harm (such as food in a refrigerator spoiling), or experience potential health impacts if they rely on a medical device and do not have a backup source of power.
Lightning is relatively rare in Orinda. The area may see only a few lightning storms or none at all each year. Orinda, like most of California, records less than one lightning strike per square mile annually. However, when lightning does occur, it can cause significant harm, including setting fires. Ten of California’s 20 largest wildfires, six of the most destructive, and three of the deadliest were at least partially caused by lightning strikes. Lightning can also cause trees to fall on power lines, buildings, or cars. Although rare, people can be directly struck by lightning, which can cause injury or death.
The most vulnerable to severe weather are those who may be directly exposed to the hazard, such as outdoor workers and persons experiencing homelessness; those who may live in less structurally resilient buildings, such as households in poverty, immigrant communities, persons with chronic illnesses and/or disabilities, and low-resourced people of color; and those who may have difficulty preparing or responding to severe weather due to mobility or language barriers. These populations include persons without access to transportation or communication and seniors living alone.
Buildings and infrastructure, such as bridges, evacuation routes and roadways, flood-control structures, and residential structures are highly vulnerable to severe weather, and they can be damaged by high winds, heavy rainfall, and debris carried by severe storms. Heavy rainfall and severe winds that damage or block transportation systems can also disrupt public transit services, which can be delayed or suspended for days or weeks depending on the severity of the damage.
Extreme winds and heavy rainfall can also harm ecosystems by causing large volumes of sediment to flow into riparian ecosystems, trees to fall in riparian habitat, and sudden oak death to spread more quickly through oak woodland forests. Extreme heat and drought conditions may weaken natural ecosystems and prevent them from recovering from severe weather events.
Wildfire and Smoke
Figure 8 shows the FHSZs in and surrounding Orinda, which include very high FHSZs in the local responsibility area, as well as high and very high FHSZs in the surrounding state responsibility area. Areas in the northwest and central northern portion of the city are within a very high FHSZ. Many of these high-risk areas are also the most difficult to access, as they are at the end of narrow, winding roads bordering undeveloped hillsides. In addition, areas adjacent to the city that are susceptible to wildfires are also of concern as these conditions could exacerbate vulnerabilities within the city. The city is also within the wildland-urban interface, which increases the risk of wildfires spreading through the community. As shown in Figure 9, the wildland-urban interface in Orinda, as designated by MOFD, covers most of the community, except for the areas immediately around the BART station and the far southeast corner of Orinda. The wildland-urban interface is a zone of transition between natural vegetation and developed lands where wildfires can move from burning just vegetation to also damaging buildings and infrastructure.
CAL FIRE Wildland-Urban Interface
As shown on Figure 9, the CAL FIRE designated wildlandurban interface is made up of three distinct zones:
Wildfires are a regular feature of the landscape in much of California. They can be sparked by lightning, malfunctioning equipment, vehicle crashes, or many other causes. Warmer temperatures, an increase in drought conditions, and extreme wind events, are likely to create more fuel for fires in natural and rural areas, leading to a greater chance that a spark will grow into a potentially dangerous blaze. Climate change is also expected to extend the fire season throughout much (or even all) of the year. Smoke from wildfires, both locally and elsewhere in northern California, also creates a significant health risk in the region. Because wildfires burn the trees and other vegetation that help stabilize a hillside and absorb water, more areas burned by fire may also lead to an increase in landslides in existing landslide-prone areas.
1. Intermix Zone. Housing development or improved parcels interspersed in an area dominated by wildland vegetation subject to wildfire.
2. Interface Zones. Dense housing next to vegetation, but not dominated by wildland vegetation, that can burn in a wildfire.
3. Influence Zone. Wildfiresusceptible vegetation within 1.5 miles from the wildland-urban interface or wildland-urban intermix zones.
Source: CAL FIRE. 2019. Wildland Urban Interface. https://frap.fire.ca.gov/media/10300/wui _19_ada.pdf
As shown in Figure 8 and Figure 9, several building types are in very high FHSZs and the wildlandurban interface areas. The portion of northwestern Orinda that is within a very high FHSZ contains primarily residential land uses. Homes can be damaged or destroyed by wildfires, rendering the structure uninhabitable and reducing the number of housing units within the city. Indoor air quality can be reduced if smoke flows into homes and residential structures, potentially damaging the structure and internal contents. Schools including Sleepy Hollow Elementary, Wagner Ranch Elementary, Orinda Intermediate, Glorietta Elementary, Del Rey Elementary, and Miramonte High School are within wildfire-prone areas and can be damaged or destroyed by a wildfire. The Orinda Water Treatment Plant is in a wildfire-prone area, and this facility can be damaged or ash could infiltrate the water system, disrupting the water treatment process and water delivery services throughout the city.
Nearly all populations within Orinda have a high or severe vulnerability to wildfire and smoke conditions. Those with existing health issues or limited mobility are particularly vulnerable due to the inability to quickly evacuate during a wildfire and additional illnesses that can occur due to smoke conditions. Smoke conditions, even from fires far away from Orinda, can also prevent residents from accessing public transit, due to unhealthy air quality, and ash from wildfires can degrade water supplies. Immigrant communities and low-resourced people of color may live in less-resilient structures or rental units where they do not have the ability to prepare their homes, and their homes are more likely to burn down in the event of a wildfire. These persons may be ineligible for or lack the time and resources to rebuild and recover from wildfires.
The entire energy delivery system, including electric transmission lines, can be damaged by wildfires. Planned PSPS events to prevent wildfires and damage to the energy delivery system have already impacted persons who depend on electricity for air conditioning or their medically necessary equipment.
Major roads and highways, including those that serve as evacuation routes and the bridges that connect these roadways, can be blocked by wildfire flames or debris, making it difficult for residents to evacuate and emergency personnel to reach certain areas of the city. The railway that provides services for BART can be damaged or blocked by wildfires, disrupting public transit access.
Wildfires in the city can also prevent visitors from traveling to the city to participate in outdoor recreation activities in nearby regional parks. Although the economy can likely recover from these events, repetitive wildfire and smoke events may make recovery difficult in the recreation sector. Chaparral habitat, although somewhat adapted to wildfires, can be substantially harmed by more frequent and severe fires that do not let the ecosystems recover. 22
MOFD has been proactive in addressing wildfire concerns in and around Orinda. MOFD regularly proposes, and the City has adopted, a stringent building code that applies citywide, requiring newly constructed buildings to meet elevated standards for building materials, landscaping, and operations. Other programs include a requirement that sprinkler systems be installed in many existing buildings, a program to provide free wood-chipping services to community members, inspecting defensible space in the community, and many others. These efforts have helped to increase adaptive capacity against wildfires in Orinda and provide a substantial benefit to the community, although wildfire remains a hazard of substantial concern.
In addition, the City has initiated a number of efforts to prevent wildfires and to be better equipped to address emergencies. The following list provides examples of several efforts that have been funded by Measure R:
• Roadside fuel reduction and vegetation management.
• Home Evaluation program that gives property owners a customized checklist of vegetation management and home-hardening tasks.
• Creating an incentive program and other resources to assist residents in implementing their home evaluation checklist.
• Offering chippers in each neighborhood twice yearly.
• Education and outreach for wildfire prevention and preparedness.