Rialto City Council
March 12, 2024

1 2023 LOCAL HAZARD MITIGATION PLAN

CITY OF
RIALTO
LOCAL HAZARD MITIGATION PLAN The City of Rialto - 150 S. Palm Ave., Rialto, CA 92376 October 13, 2023 Prepared by

2 2023 LOCAL HAZARD MITIGATION PLAN
Table of Contents Section 1 – Introduction .......................................................................................................... 5 1.1 – Hazard Mitigation .................................................................................................................... 5 1.2 – Purpose and Authority ............................................................................................................. 6 Section 2 – Community Profile ................................................................................................. 8 2.1 – Setting and Location ................................................................................................................ 8 2.2 – History ..................................................................................................................................... 9 2.3 – Climate .................................................................................................................................. 10 2.4 – Climate Change ...................................................................................................................... 11 2.5 – Demographics ........................................................................................................................ 12 2.6 – Population and Racial/Ethnic Composition ............................................................................ 12 2.7 – Education ............................................................................................................................... 13 2.8 – Housing and Development ..................................................................................................... 13 2.9 – Economy ................................................................................................................................ 15 2.10 – Infrastructure ....................................................................................................................... 17 Section 3 – Hazard Identification and Risk Assessment .......................................................... 20 3.1 Historic Disaster Declarations ................................................................................................... 20 3.1 Hazard Selection ....................................................................................................................... 25 3.2 – Hazard Scoring and Prioritization ........................................................................................... 26 3.3 – Global Climate Change ........................................................................................................... 28 3.4 – Overall Probability of Occurrence .......................................................................................... 31 3.5 – Hazard Profiles ....................................................................................................................... 32 3.5.1 – Extreme Heat ...................................................................................................................... 32 3.5.2 – Power Outages ................................................................................................................... 35 3.5.3 – Drought .............................................................................................................................. 37 3.5.4 – Wildfire ............................................................................................................................... 41 Fire Danger Rating System ................................................................................................................................. 45 3.5.5 – Hazardous Materials ........................................................................................................... 50 3.5.6 – Cyberattack ......................................................................................................................... 56

3 2023 LOCAL HAZARD MITIGATION PLAN

3.5.7 – Terrorism ............................................................................................................................ 58 3.5.8 – Earthquake ......................................................................................................................... 60 The Richter Magnitude Scale ............................................................................................................................. 63 Modified Mercalli Intensity Scale for Earthquakes ............................................................................................ 63 3.5.9 – Epidemic / Pandemic .......................................................................................................... 67 3.5.10 – Flood ................................................................................................................................. 69 3.5.11 – Severe Rainfall .................................................................................................................. 76 Measuring Heavy Rain Events ............................................................................................................................ 77 3.5.12 – Severe Wind ...................................................................................................................... 81 Section 4 – Vulnerability Assessment ..................................................................................... 86 4.2 Critical Facility List .................................................................................................................... 87 Critical Facility List .............................................................................................................................................. 88 Section 5 – Capability Assessment ....................................................................................... 108 5.1 – Planning and Regulatory Capabilities ................................................................................... 108 Policy and Regulatory Resources ..................................................................................................................... 109 Administrative and Staff Resources ................................................................................................................. 109 5.2 – Fiscal Capability ................................................................................................................... 111 5.3 – Education and Outreach Capability ...................................................................................... 112 5.4 – National Flood Insurance Program Participation .................................................................. 113 Section 6 – Mitigation Strategy ........................................................................................... 115 6.1 Mitigation Goals and Objectives ............................................................................................. 116 6.2 Mitigation Action Plan ............................................................................................................ 117 6.3 Mitigation Actions .................................................................................................................. 119 Section 7 – Planning Process ............................................................................................... 140 7.1 – Planning Process .................................................................................................................. 140 7.2 – Plan Update ......................................................................................................................... 143 7.3 – Stakeholder Involvement ..................................................................................................... 143 7.4 – Public Involvement .............................................................................................................. 145 7.5 – Plan Incorporation ............................................................................................................... 146 7.6 – Plan Maintenance ................................................................................................................ 147 Monitoring, Evaluating and Updating the Plan ............................................................................. 147

4 2023 LOCAL HAZARD MITIGATION PLAN
Incorporation into Existing Planning Mechanisms ........................................................................ 148 Continued Public Participation in the Plan Maintenance Process .................................................. 149 7.7 – Plan Adoption ...................................................................................................................... 149 Appendices ......................................................................................................................... 151 Appendix A: Sample Adoption Resolution .................................................................................... 151 Adopting the City of Rialto Hazard Mitigation Plan ....................................................................... 151 Appendix B: LHMP Approval Process ............................................................................................ 152 Appendix C: Relevant Municipal Code Sections ............................................................................ 154 Appendix D: Public Engagement Survey Results ........................................................................... 181

5 2023 LOCAL HAZARD MITIGATION PLAN
Section 1 – Introduction 1.1 – Hazard Mitigation Hazard mitigation is a proactive approach that helps to minimize the impact of natural disasters and other emergencies on individuals, communities, and businesses. It involves identifying and assessing potential hazards, developing strategies and plans to reduce their impact, and implementing measures to protect people and property from harm. This can include measures such as building codes and standards, zoning regulations, evacuation plans, early warning systems, and disaster-resistant infrastructure. The goal of hazard mitigation is to reduce the frequency and severity of disasters, minimize their impact on communities, and promote resilience and sustainability in the face of future emergencies. By taking a proactive approach to disaster risk reduction, we can help to save lives, reduce the economic impact of disasters, and ensure that communities are better prepared to respond to and recover from emergencies. Hazard mitigation planning improves a community's ability to effectively respond to natural disasters by establishing plans for maintaining continuity of operations for both government and community entities. The process involves identifying attainable goals to reduce the risk of injury, loss of life, and property damage from hazardous events, and developing strategies and activities to mitigate their effects. The hazard mitigation plan is designed to be a participatory process that involves government agencies, stakeholders, and the public. The planning process includes scheduled events that encourage participation and ensure that a comprehensive approach is taken to address current and future hazards. By incorporating a systematic and inclusive approach, the hazard mitigation plan helps to reduce the community's vulnerability to disasters and promote resilience. As the impacts of global climate change have become increasingly apparent, explicitly integrating climate concerns into hazard mitigation planning has become necessary to most fully understanding a jurisdiction’s future risk and designing effective strategies to mitigate that risk. The most recent update of FEMA’s local hazard mitigation planning guidance, effective as of April 2023, includes a deeper focus on climate impacts and adaptation.

6 2023 LOCAL HAZARD MITIGATION PLAN

1.2 – Purpose and Authority The City of Rialto’s 2023 Local Hazard Mitigation Plan (LHMP) outlines the potential natural and human-caused hazards that pose a threat to the citizens, resources, and property in the city. The plan also outlines the city's objectives and commitment to reducing the risks associated with these hazards. This LHMP has been prepared in conjunction with several other emergency management plans as well as an update to the City’s Safety Element, a component of the General Plan. Every effort has been made to ensure that the LHMP fits with and echoes these other documents so as to increase resilience city-wide. The focus of this LHMP is on the hazards that pose the greatest risk to the city, as determined through a comprehensive hazard risk assessment and input from local officials. Hazards of lesser concern may still be evaluated but may not be fully addressed in this plan update. The updated risk assessment will help the city prioritize and update mitigation actions based on the hazards that pose the greatest risk to lives and property. The LHMP has been developed in compliance with current federal and state regulations governing local hazard mitigation plans and has been adopted in accordance with standard local procedures. The plan will be monitored regularly and revised as necessary to maintain compliance with the provisions, rules, and legislation outlined in Section 322 of the Robert T. Stafford Disaster Relief and Emergency Assistance Act, FEMA's Final Rule published in the Federal Register, the Flood Insurance Reform Act of 2004 and 2012, and the Homeowner Flood Insurance Affordability Act. The U.S. Congress passed the Disaster Mitigation Act of 2000 (DMA 2000), which amended the Robert T. Stafford Disaster Relief and Emergency Assistance Act and emphasized the need for state and local governments to closely coordinate their mitigation planning activities. The development of a hazard mitigation plan is a specific eligibility requirement for any local government applying for federal mitigation grant funds. These funds include Building Resilient Infrastructures in Communities (BRIC), Hazard Mitigation Grant Program (HMGP) and Flood Mitigation Assistance (FMA), all administered by FEMA. • Building Resilient Infrastructure in Communities (BRIC): BRIC aims to encourage natural hazard risk reduction activities that incentivize public infrastructure and disadvantaged communities, mitigate risk to community lifelines, incorporate nature-based solutions, enhance climate resilience and adaptation, and increase funding to applicants who facilitate the adoption and enforcement of the latest published editions of building codes. Mitigation projects that align with multiple program priorities are highly encouraged. • Hazard Mitigation Grant Program (HMGP): HMGP provides funds to states, territories,

7 2023 LOCAL HAZARD MITIGATION PLAN
Indian tribal governments, local governments, and eligible private non-profit organizations (such as hospitals and special needs populations) following a presidential disaster declaration. • Flood Mitigation Assistance (FMA): Supports implementing flood mitigation, acquisition, or elevation of flood-prone homes. The community must also participate in the National Flood Insurance Program (NFIP) since one of the goals of FMA is to reduce or eliminate NFIP claims.

8 2023 LOCAL HAZARD MITIGATION PLAN
Section 2 – Community Profile This is an overview of the City of Rialto with information about the community’s physical setting, history, economy and demographics, current and future land uses, and key infrastructure. The Community Profile establishes the baseline conditions that inform the development of hazard mitigation actions described in Section 5. 2.1 – Setting and Location The City of Rialto is situated in San Bernardino County, California, in the heart of the Inland Empire, a cluster of municipalities to the east of Los Angeles. Rialto is approximately 60 miles from Los Angeles and 90 miles northeast of San Diego. The city is easily accessible via the I-10, I-15, and 210 Freeway, as well as historic Route 66 (Foothill Blvd.). Around 55% of Rialto’s workforce commute more than 10 miles, and the average travel time for commuters in Rialto ranges from 33.6 to 37.6 minutes. Light rail serves Rialto through the Rialto station on the Metrolink San Bernardino Line. The San Bernardino Line requires approximately an hour and twenty minutes for a round trip to Los Angeles. Rialto is located on a broad alluvial plain at the base of Cajon Pass, which separates the San Gabriel Mountains, the San Bernardino Mountains, and Lytle Creek. The elevation of the city decreases from 1,960 feet above sea level at the intersection of I-15 and Sierra/Riverside Avenue to 900 feet above sea level in the Agua Mansa Industrial Corridor area, with an average slope of 2% or 117 feet per mile. Key watercourses in Rialto include the Santa Ana River and Lytle Creek, and the city's boundaries overlap with the Rialto/Colton, Lytle Creek, and North Riverside Basin watersheds.

9 2023 LOCAL HAZARD MITIGATION PLAN
Map of Rialto (source: Google Maps) 2.2 – History Rialto has a rich history dating back to the late 1800s. The city was originally founded in 1886 and was originally known as the Rialto Railroad Depot. At the time, the city was just a small railway stop that was used to serve the nearby citrus and agriculture industries. During the early 1900s, Rialto experienced significant growth and development as the railway system expanded and more people moved to the area. In 1911, the city was officially incorporated and began to expand its borders, annexing neighboring communities and growing in population. In 1913, Foothill Boulevard underwent repairs and was subsequently incorporated into the U.S. highway system as a section of U.S. Route 66.

10 2023 LOCAL HAZARD MITIGATION PLAN
In the 1920s and 1930s, Rialto became known for its thriving dairy industry, and it became one of the largest dairy producers in the state of California. The city also saw growth in its manufacturing and retail sectors during this time. During World War II, the U.S. Army utilized the Rialto Ammunition Storage point to provide support for operations in the Pacific theater. The 160-acre site was later sold to defense contractors and private corporations. The site has been listed as a Superfund site and remediation efforts began in 2020. In the post-World War II era, the city saw a significant increase in residential development as veterans returned home and sought out new homes. In the 1960s and 1970s, the city continued to grow, with the construction of new homes, businesses, and retail centers. Today, Rialto continues to experience growth and development, and it remains a hub for business and commerce in the Inland Empire region of Southern California. 2.3 – Climate Rialto covers a total area of 21.9 square miles (56.7 km²), with 21.9 square miles (56.6 km²) being land and just 0.05% being water. The City has a Mediterranean climate, which is characterized by wet, cool to chilly winters with frost and chilly morning temperatures, and hot, dry summers. Rialto experiences an average of 16 inches (41 cm) of precipitation per year, mostly in the form of rain, hail, or light snow showers. The northern-most neighborhood of Rialto occasionally receives snow due to its elevation of approximately 3,000 feet (910 m) above sea level, while the rest of the city is typically out of the snowfall range. The temperature in Rialto ranges from highs in the 60s (Fahrenheit) in January to 90s in July. The arid climate during summer results in the absence of tropospheric clouds and causes temperatures to rise to Class Orange levels, as designated by NOAA. The seasonal Santa Ana winds, which are felt strongly in Rialto and the surrounding San Bernardino area, channel warm and dry air through nearby Cajon Pass during autumn and significantly increase the wildfire danger in the foothill, canyon, and mountain communities.

11 2023 LOCAL HAZARD MITIGATION PLAN
Minimum and Maximum Temperature Averages for Rialto
Precipitation Averages for Rialto 2.4 – Climate Change The impacts of climate change on Rialto, California are expected to be similar to those experienced by other cities in the region. As the average global temperature continues to rise, temperatures in California are projected to increase, leading to more frequent and intense heat waves, droughts, and wildfires. Additionally, changing precipitation patterns may result in decreased water availability in the region, putting stress on both local water resources and the agricultural sector. More detailed information on climate change and its impacts on Rialto can be found throughout Section 3.

12 2023 LOCAL HAZARD MITIGATION PLAN

2.5 – Demographics As of the 2021 United States Census’ American Community Survey 1-year estimate, the population of Rialto, California was estimated to be 104,380. The racial and ethnic makeup of the city was predominantly Hispanic or Latino, with a significant African American population and smaller percentages of White, Asian, and other racial and ethnic groups. Rialto has a relatively young population, with a median age of 32 years. A significant portion of the population was under the age of 18, reflecting the city's status as a family-oriented community. The city has a relatively low household income compared to the rest of the state, with a median household income of $69,982. However, the cost of living in Rialto is relatively low, making it an affordable option for families and individuals. 57.4% of the city’s population speaks a language other than English. Spanish is the city’s predominant language other than English, spoken by 54.8% of the population. 6.1% of the population under age 65 has a disability, and 11.9% of the population under age 65 lacks health insurance coverage. Unless otherwise specified, all tables following in Section 2 use data from the U.S. Census Bureau’s 2020 Decennial Census and the American Community Survey’s 1-Year Estimates. 2.6 – Population and Racial/Ethnic Composition Label Estimate SEX AND AGE Total population 104,380 Male 51,225 Female 53,155 Under 18 years 31,362 65 years and over 9,957 RACE Two or more races 18,436 One race 85,944 White 13,235 Black or African American 12,500 American Indian and Alaska Native 1,005 Asian 1,992 Native Hawaiian and Other Pacific Islander 168

13 2023 LOCAL HAZARD MITIGATION PLAN
Some other race 57,044 Hispanic or Latino (of any race) 79,822

2.7 – Education Label Estimate Estimate Population 25 years and over 64,319 (X) Less than 9th grade 6,930 10.8% 9th to 12th grade, no diploma 8,617 13.4% High school graduate (includes equivalency) 22,154 34.4% Some college, no degree 13,326 20.7% Associate degree 4,615 7.2% Bachelor's degree 6,363 9.9% Graduate or professional degree 2,314 3.6% High school graduate or higher 48,772 75.8% Bachelor's degree or higher 8,677 13.5% 2.8 – Housing and Development The City of Rialto has historically been a working-class community. Its relative affordability compared to other nearby cities has been a draw for populations including Latino and African American. Newer development on the north side of the city, including redevelopment of a former golf course, has added pricier housing options. There is potential for the City to annex several areas north of its current boundary. This would add more affluent housing to the City’s housing mix; however, the position of these areas in the wildfire urban interface would increase the City’s vulnerability to wildfire. As of the present time of writing, Rialto’s General Plan dates from 2010 and is currently being updated by section. As such, we have chosen to use updated housing and land use data from several other sources, including the Southern California Area Governments’ Local Housing Data report (August 2020) and U.S. Census Bureau updates (2021). Future addenda or revisions of the hazard mitigation plan should refer more directly to the city’s current General Plan. As of July 2021: • Owner-occupied housing rate – 62.1% • Median value of owner-occupied housing units - $350,000 • Median selected monthly owner costs with a mortgage - $1,869 • Median gross rent - $1,405.

14 2023 LOCAL HAZARD MITIGATION PLAN
Map 2.2: Rialto Zoning Codes (source: SCAG Rialto Profile, 2019)

15 2023 LOCAL HAZARD MITIGATION PLAN
Table 2.5: Rialto Housing Types
Table 2.6:: Housing Units by Structure Built 2.9 – Economy According to data from the US Census Bureau, the estimated median household income as of 2021 is $69,982. Per capita income in Rialto as of 2021 was estimated to be $24,346. In terms of employment, the city is home to a mix of blue-collar and white-collar workers, with industries ranging from manufacturing and retail to healthcare and education. The economy of Rialto is a diverse mix of healthcare, retail, manufacturing, and logistics industries. The Rialto Unified School District is the largest single employer in the city, and the healthcare sector is the largest employment sector in the city, with San Bernardino County Health System and Arrowhead Regional Medical Center being two of the biggest players. Other major employers include Amazon, Walmart, and Kohl's.

16 2023 LOCAL HAZARD MITIGATION PLAN
Rialto is home to several key facilities in the manufacturing and storage sectors, including the largest rail yard classification facility in the western United States, a large petroleum storage and distribution center, and various distribution centers for Target, Black & Decker, and Staples. The city also boasts manufacturers such as Eagle Roofing, Tree Top, and Biscomerica. Rialto's business-friendly environment, low labor costs, top-notch transportation system, access to two major rail services (Union Pacific and Burlington Northern/Santa Fe), and proximity to three airports make it a desirable location for industrial development. The city has implemented a proactive Redevelopment Agency and has been designated an Enterprise Zone and Recycling Market Development Zone to further support its economic growth. The retail trade sector is also robust in Rialto, with shopping centers and strip malls scattered throughout the city. Additionally, companies such as IMI Cornelius have operations in the city, making manufacturing a contributor to Rialto's economy. Label Estimate Percent EMPLOYMENT STATUS Civilian labor force 48,369 62.8% Employed 43,961 57.0% Unemployed 4,408 5.7% Unemployment Rate (X) 9.1% OCCUPATION Management, business, science, and arts occupations 10,131 23.0% Service occupations 6,976 15.9% Sales and office occupations 8,036 18.3% Natural resources, construction, and maintenance occupations 5,653 12.9% Production, transportation, and material moving occupations 13,165 29.9% INDUSTRY Agriculture, forestry, fishing and hunting, and mining 855 1.9% Construction 5,171 11.8% Manufacturing 3,600 8.2% Wholesale trade 1,675 3.8% Retail trade 4,576 10.4% Transportation and warehousing, and utilities 8,427 19.2% Information 147 0.3% Finance and insurance, and real estate and rental and leasing 1,584 3.6% Professional, scientific, and management, and administrative and waste management services 3,482 7.9% Educational services, and health care and social assistance 8,648 19.7%

17 2023 LOCAL HAZARD MITIGATION PLAN
Arts, entertainment, and recreation, and accommodation and food services 1,772 4.0% Other services, except public administration 1,691 3.8% Public administration 2,333 5.3% CLASS OF WORKER Private wage and salary workers 36,460 82.9% Government workers 5,557 12.6% Self-employed in own not incorporated business workers 1,845 4.2% Unpaid family workers 99 0.2% INCOME AND BENEFITS (IN 2021 INFLATION-ADJUSTED DOLLARS) Total households 29,043 29,043 Less than $10,000 624 2.1% $10,000 to $14,999 1,343 4.6% $15,000 to $24,999 2,179 7.5% $25,000 to $34,999 2,478 8.5% $35,000 to $49,999 2,627 9.0% $50,000 to $74,999 6,326 21.8% $75,000 to $99,999 4,993 17.2% $100,000 to $149,999 4,938 17.0% $150,000 to $199,999 2,083 7.2% $200,000 or more 1,452 5.0% Median household income (dollars) 69,982 (X) Mean household income (dollars) 84,201 (X) Per capita income (dollars) 24,346 (X) PERCENTAGE OF FAMILIES AND PEOPLE WHOSE INCOME IN THE PAST 12 MONTHS IS BELOW THE POVERTY LEVEL All families (X) 9.7% All people (X) 11.0% 2.10 – Infrastructure Electricity and Natural Gas: The city is served by Southern California Edison (SCE), which is one of the largest electric utilities in the United States. SCE provides electricity to over 15 million people across Southern California, including Rialto. Rialto also has a growing electric vehicle (EV) infrastructure, with several public charging stations located throughout the city. These charging stations are part of SCE's Charge Ready program, which aims to install more than 38,000 EV charging ports across Southern California by 2025. The city is also served by Southern California Gas Company (SoCalGas), which is one of the largest natural gas utilities in the United States. SoCalGas provides natural gas to over 21 million customers across Southern California, including Rialto. 8 18
2023 LOCAL HAZARD MITIGATION PLAN
Water Infrastructure: The City of Rialto owns and operates its own water utility, as well as several other water providers in parts of the City. The water utility in Rialto sources its water from a combination of local groundwater wells and imported water from the State Water Project and the Colorado River. The water is treated at several treatment plants to ensure it meets or exceeds state and federal drinking water standards. The treated water is then delivered to customers through a network of water mains, service lines, and meters. The city has over 200 miles of water mains and more than 15,000 service connections. Wastewater Infrastructure: The City of Rialto owns and operates its own wastewater utility. Wastewater infrastructure in Rialto consists of a network of sewer mains, lift stations, and treatment plants. Wastewater from homes and businesses is collected in sewer mains and transported to one of two treatment plants: the Rialto Water Services Treatment Plant or the West Valley Water District Treatment Plant. Transportation: The major highways that run through Rialto include Interstate 10, Interstate 15, State Route 210, and State Route 66. Other important roads in Rialto include Foothill Boulevard, Riverside Avenue, and Base Line Road. • Interstate 10: Also known as the San Bernardino Freeway, I-10 is a major east-west highway that runs across Southern California. It passes through Rialto in the southern part of the city and connects it to other major cities such as San Bernardino, Riverside, and Los Angeles. • State Route 210: Also known as the Foothill Freeway, SR-210 is a major freeway that runs east-west through the San Gabriel Valley and the Inland Empire. It passes through Rialto in the northern part of the city and connects it to neighboring cities such as Fontana, San Bernardino, and Pasadena. • State Route 66: Also known as the historic Route 66, SR-66 runs east-west through Southern California and passes through Rialto in the northern part of the city. It connects Rialto to other cities such as Fontana, Rancho Cucamonga, and Claremont. Rialto is served by the Omnitrans public transit system, which operates bus services throughout San Bernardino County. Omnitrans has several bus stops and routes in Rialto that connect the city to other nearby cities such as San Bernardino, Fontana, and Ontario. The Burlington Northern Santa Fe (BNSF) Railway has a large intermodal facility in Rialto, which handles the transfer of goods between trains and trucks. The facility plays a crucial role in the logistics and supply chain operations of the region.

19 2023 LOCAL HAZARD MITIGATION PLAN
Metrolink provides service to Rialto through the San Bernardino Line, which connects the city to downtown Los Angeles and other cities along the route. Metrolink service in Rialto is provided through the Rialto Metrolink Station, which is located at 1350 W. Rialto Avenue. The station is situated on the San Bernardino Line and is one of the 26 stations that Metrolink serves throughout its network. Metrolink trains operate on weekdays, with limited service on weekends and holidays. Trains arrive and depart from the Rialto Station approximately every 60 minutes during peak hours and every 90 minutes during off-peak hours. The first train arrives at the Rialto Station at around 4:00 AM, and the last train departs at around 9:00 PM. The San Bernardino Line provides service to several stations along its route, including San Bernardino, Rancho Cucamonga, and Downtown Los Angeles.

20 2023 LOCAL HAZARD MITIGATION PLAN
Section 3 – Hazard Identification and Risk Assessment Element B: Risk Assessment Requirements B1. Does the plan include a description of the type, location and extent of all natural hazards that can affect the jurisdiction? Does the plan also include information on previous occurrences of hazard events and on the probability of future hazard events? (Requirement 44 CFR § 201.6(c)(2)(i)) B2. Does the plan include a summary of the jurisdiction's vulnerability and the impacts on the community from the identified hazards? Does this summary also address NFIP insured structures that have been repetitively damaged by floods? (Requirement 44 CFR § 201.6(c)(2)(ii)) This section discusses the types of hazards that might reasonably happen in Rialto. It describes how they are measured, a history of these hazards in and around Rialto, and the future risk they pose. This chapter also discusses how hazards in the plan were selected and prioritized. 3.1 Historic Disaster Declarations Since 1953, San Bernardino County has received 30 total Federal disaster declarations. The following data comes from FEMA’s Disaster Declarations for States and Counties (https://www.fema.gov/data-visualization/disaster-declarations-states-and-counties; retrieved February 6, 2024). FEMA Declaration String State Fiscal Year Declared Incident Type Incident Subcategory County DR-211-CA CA 1966 Flood Heavy Rains & Flooding San Bernardino (County) DR-223-CA CA 1967 Flood Severe Storms & Flooding San Bernardino (County) DR-253-CA CA 1969 Flood Severe Storms & Flooding San Bernardino (County) DR-295-CA CA 1970 Fire Forest & Brush Fires San Bernardino (County)

21 2023 LOCAL HAZARD MITIGATION PLAN
DR-521-CA CA 1976 Flood Flooding, Tropical Storm Kathleen San Bernardino (County) DR-547-CA CA 1978 Flood Coastal Storms, Mudslides & Flooding San Bernardino (County) DR-615-CA CA 1980 Flood Severe Storms, Mudslides & Flooding San Bernardino (County) DR-635-CA CA 1981 Fire Brush & Timber Fires San Bernardino (County) DR-677-CA CA 1983 Coastal Storm Coastal Storms, Floods, Slides & Tornadoes San Bernardino (County) DR-687-CA CA 1983 Flood Flooding San Bernardino (County) DR-690-CA CA 1983 Flood Flash Flooding San Bernardino (County) DR-872-CA CA 1990 Fire Fires San Bernardino (County) DR-894-CA CA 1991 Freezing Severe Freeze San Bernardino (County) DR-935-CA CA 1992 Flood Rain/Snow/Wind Storms, Flooding, Mudslides San Bernardino (County) DR-947-CA CA 1992 Earthquake Earthquake & Aftershocks San Bernardino (County) DR-979-CA CA 1993 Flood Severe Winter Storm, Mud & Land Slides, & Flooding San Bernardino (County) DR-1005-CA CA 1994 Fire Fires, Mud/Landslides, Flooding, Soil Erosion San Bernardino (County)

22 2023 LOCAL HAZARD MITIGATION PLAN
DR-1044-CA CA 1995 Severe Storm Severe Winter Storms, Flooding, Landslides, Mud Flows San Bernardino (County) DR-1046-CA CA 1995 Severe Storm Severe Winter Storms, Flooding Landslides, Mud Flow San Bernardino (County) DR-1203-CA CA 1998 Severe Storm Severe Winter Storms And Flooding San Bernardino (County) EM-3140-CA CA 1999 Fire Ca-Wildfires-08/25/1999 San Bernardino (County) FM-2425-CA CA 2002 Fire Bluecut Fire San Bernardino (County) FM-2433-CA CA 2002 Fire Louisiana Fire San Bernardino (County) FM-2464-CA CA 2002 Fire Williams Fire San Bernardino (County) FM-2491-CA CA 2003 Fire Ca-Locust Wildfire-08-19-2003 San Bernardino (County) FM-2497-CA CA 2003 Fire Ca-Bridge Fire-09-05-2003 San Bernardino (County) FM-2501-CA CA 2004 Fire Ca-Grand Prix Fire-10-23-2003 San Bernardino (County) FM-2503-CA CA 2004 Fire Old Fire San Bernardino (County) DR-1498-CA CA 2004 Fire Wildfires, Flooding, Mudflow And Debris Flow Directly Related T San Bernardino (County)

23 2023 LOCAL HAZARD MITIGATION PLAN
DR-1577-CA CA 2005 Severe Storm Severe Storms, Flooding, Debris Flows, And Mudslides San Bernardino (County) DR-1585-CA CA 2005 Severe Storm Severe Storms, Flooding, Landslides, And Mud And Debris Flows San Bernardino (County)
EM-3248-CA CA 2005 Hurricane Hurricane Katrina Evacuation San Bernardino (County) FM-2653-CA CA 2006 Fire Sawtooth Fire Complex San Bernardino (County) DR-1689-CA CA 2007 Freezing Severe Freeze San Bernardino (County) FM-2728-CA CA 2007 Fire Butler 2 Fire San Bernardino (County) FM-2738-CA CA 2008 Fire Grass Valley Fire San Bernardino (County) EM-3279-CA CA 2008 Fire Wildfires San Bernardino (County) DR-1731-CA CA 2008 Fire Wildfires, Flooding, Mud Flows, And Debris Flows San Bernardino (County) FM-2792-CA CA 2009 Fire Freeway Fire Complex San Bernardino (County) FM-2833-CA CA 2009 Fire Oak Glen Fire San Bernardino (County) FM-2836-CA CA 2009 Fire Pendleton Fire San Bernardino (County) FM-2841-CA CA 2010 Fire Sheep Fire San Bernardino (County)

24 2023 LOCAL HAZARD MITIGATION PLAN
DR-1884-CA CA 2010 Severe Storm Severe Winter Storms, Flooding, And Debris And Mud Flows San Bernardino (County) DR-1952-CA CA 2011 Flood Severe Winter Storms, Flooding, And Debris And Mud Flows San Bernardino (County) FM-2955-CA CA 2011 Fire Hill Fire San Bernardino (County) FM-5089-CA CA 2015 Fire North Fire San Bernardino (County) FM-5144-CA CA 2016 Fire Pilot Fire San Bernardino (County) FM-5147-CA CA 2016 Fire Blue Cut Fire San Bernardino (County) EM-3415-CA CA 2019 Earthquake Earthquakes San Bernardino (County) FM-5301-CA CA 2020 Fire Hillside Fire San Bernardino (County) EM-3428-CA CA 2020 Biological Covid-19 San Bernardino (County) DR-4482-CA CA 2020 Biological Covid-19 Pandemic San Bernardino (County) FM-5325-CA CA 2020 Fire Apple Fire San Bernardino (County) FM-5350-CA CA 2020 Fire El Dorado Fire San Bernardino (County) DR-4569-CA CA 2021 Fire Wildfires San Bernardino (County) FM-5381-CA CA 2021 Fire Blue Ridge Fire San Bernardino (County)

25 2023 LOCAL HAZARD MITIGATION PLAN
EM-3591-CA CA 2023 Flood Severe Winter Storms, Flooding, And Mudslides San Bernardino (County) EM-3592-CA CA 2023 Flood Severe Winter Storms, Flooding, Landslides, And Mudslides San Bernardino (County)

3.1 Hazard Selection Hazards for the 2023 LHMP were determined by examining hazards previously analyzed in the most recent LHMP revision draft as of 2012 as well as additional hazards identified by the City through internal solicitation from participants in the internal interview process for the LHMP. This series of interviews allowed participants from a variety of City departments to directly inform the Planning Team of their individual perceptions of hazards, vulnerabilities, and desirable mitigation actions. The National Risk Index identifies 18 specific hazards that may affect communities across the United States. Not all of these hazards were included in the 2023 LHMP. Each hazard is addressed below along with justifications as to why they may not have been included. Hazard Included Explanation Avalanche No The City of Rialto does not experience significant snowfall; therefore, this hazard Is not applicable to the City. Coastal Flooding No The City of Rialto does not have any coastline; therefore, this hazard is not applicable to the City. Cold Wave No Southern California is known for its temperate and warm climate; therefore, this hazard is not applicable to the City. Drought Yes This hazard is included in the THMP. Earthquake Yes This hazard is included in the THMP. Hail No This hazard was not identified through any of the interviews with City staff; therefore, this hazard was not determined to be significant enough to include in the LHMP. Related hazards are included as “Heavy Rain” and “Severe Wind”. Heat Wave Yes This hazard is included under “Extreme Heat”.

26 2023 LOCAL HAZARD MITIGATION PLAN
Hurricane No Hurricanes rarely impact Southern California; therefore, this hazard is not applicable to the City. Similar impacts are examined under “Heavy Rain” and “Extreme Wind”. Ice Storm No Southern California is known for its temperate and warm climate; therefore, this hazard is not applicable to the City. Landslide No Due to its topography, the City of Rialto does not face significant threats from landslide; therefore, this hazard is not applicable to the City. Lightning No This hazard was not identified through any of the interviews with City staff; therefore, this hazard was not determined to be significant enough to include in the LHMP. Related hazards are included as “Heavy Rain” and “Severe Wind”. Riverine Flooding No There are no significant waterways within the boundaries of the City of Rialto; therefore, this hazard is not applicable to the City. Strong Wind Yes This hazard is included as “Severe Wind”. Tornado No Tornadoes are extremely rare in Southern California; therefore, this hazard is not applicable to the City. Tsunami No The City of Rialto does not border a major body of water and is sufficiently inland to be insulated from immediate tsunami impacts; therefore, this hazard is not applicable to the City. Volcanic Activity No There are no active volcanos in Southern California; therefore, this hazard is not applicable to the City. Wildfire Yes This hazard is included in the LHMP. Winter Weather No Southern California is known for its temperate and warm climate; therefore, this hazard is not applicable to the City. 3.2 – Hazard Scoring and Prioritization On April 6, 2023, a hazards and vulnerability assessment workshop was conducted with the City of Rialto. During the workshop, attendees evaluated the risk of hazards included in previous LHMP documents as well as additional hazards suggested by attendees.

27 2023 LOCAL HAZARD MITIGATION PLAN
Hazard Severity (Present) Probability (Present) Severity (Future) Probability (Future) Modified CPRI Extreme Heat 3 3 4 3 4.8 Power Outages 3 2 3 3 4.05 Drought 2 2 3 3 3.75 Wildfire 2 2 3 3 3.75 Hazardous Materials 3 2 2 2 3.3 Cyberattack 2 2 2 2 3 Terrorism 2 2 2 2 3 Earthquake 2 2 2 2 3 Infectious Disease 3 1 3 1 2.7 Flood 2 1 2 2 2.55 Heavy Rain 1 1 1 2 1.95 Severe Wind 1 2 1 1 1.95 Table 3.1: Modified CPRI Score Based in part on elements of the Critical Priority Risk Index, modified for an increased emphasis on future risks using standard climate risk assessment categorization, participants were asked to score the above list of hazards on a scale of 0-4 using four categories for each. Severity and probability were assigned numerical values: • 0 – Negligible (no hazards marked as negligible were included in this analysis). • 1 – Minor. • 2 – Moderate. • 3 – Major • 4 – Extreme Each hazard’s overall ranking on a 0-4 scale was discussed with City representatives and adjusted based on their comments. Based on city comments and hazards assessment, consultants assigned more detailed scores based on severity and probability on different time scales. Hazards were assigned severity and probability scores for both the present day and the future based on anticipated climate, development, and security changes. This information was used to calculate the Modified Calculated Probability Risk Index score. The CPRI is a common methodology used in hazard mitigation plans to quantify risk.

28 2023 LOCAL HAZARD MITIGATION PLAN
However, it does not give sufficient weight to future risks from climate change or other future events. The Modified CPRI is calculated in the following manner: ((Severity (Present)*0.3)+(Probability (Present)*0.45)+(Severity (Future)*0.3)+(Probability (Future)*0.45)) This hazard ranking is necessarily to some degree subjective in nature because it is based on assigning quantitative scores to informed judgements of City stakeholders. As such, it is an accurate reflection not only of hazards that the City perceives as major concerns, but of how the City prioritizes hazards and actions intended to mitigate those hazards. It is also a snapshot in time with participants rating hazards with a future-risk oriented perspective. This information directly influenced the selection of hazards in Section 6 – Mitigation Strategy. 3.3 – Global Climate Change Global climate change is one of the defining phenomena of the 21st century and is emphasized in FEMA’s revised hazard mitigation planning guidance as of April 19, 2023. Climate change is caused by increasing emissions of specific gasses, primarily carbon dioxide (CO2) and the feedback loops caused by those emissions increasing overall global temperatures. As of 2023, current concentrations of CO2 in the atmosphere are equivalent to those last seen in the Pliocene era between 2 and 5 million years ago before the Ice Ages, where global sea levels were on average 20 feet higher than today. Climate change is not, by itself, a discrete hazard, and will not be considered as such in this LHMP. Instead, climate will be considered in each individual hazard description, as well as within individual mitigation actions. Climate change is best thought of as, in security parlance, a threat multiplier, or as “loading the dice”, amplifying the impacts of existing hazards, shifting the probability of extreme events, and extending new hazards to regions that previously have not experienced them. National and intergovernmental efforts to establish consensus climate projections include the Intergovernmental Panel on Climate Change and the National Climate Assessment in the United States (the Fifth Assessment is currently in preparation). The IPCC uses a representative concentration pathway (RCP) and associated shared socioeconomic pathways (SSP) to illustrate likely outcomes of varying emissions levels.

29 2023 LOCAL HAZARD MITIGATION PLAN
At the time of writing (2024), given national pledges and observed trends in measurable emissions, the most probably emission scenario is the upper end of RCP4.5, which results in an increase of between 2.2 and 3.5 degrees Celsius over preindustrial temperatures. By 2100, a significant increase by any measure over the 1.5 degree Celsius boundary set by the 2015 Paris Accords. This outcome is subject to several significant caveats: • This assumes that all national pledges are followed through upon, which is highly questionable given political realities. • This also neglects the potential for feedback loops or unpredictable events such as major methane releases due to arctic thawing that may temporarily significantly increase greenhouse gases in the atmosphere. • Many projections assume the development and widespread use of carbon capture and sequestration (CCS) technology to draw down carbon out of the atmosphere. As

30 2023 LOCAL HAZARD MITIGATION PLAN
of yet, CCS technology has not been proven to scale, and the extent of deployment required for CCS to impact projections will be extraordinarily broad and expensive. • Finally, a consensus is not a prediction – it is a product of a scientific process that is heavily impacted by political considerations. It can be thought of as a set of ranges, not as a hard number. Many climate risk analyses today use RCP8.5, or “business as usual” projections as their baseline, which was the most likely outcome as of as little as three years ago. More recent projections have shifted to RCP4.5, but RCP8.5 is still completely in the realm of possibility and is more likely than the extremely optimistic projection of RCP1.9. Below are a few of the most relevant aspects of climate change for hazard mitigation planning:

Temperature Projections Source: U.S. Climate Resilience Toolkit Climate Explorer for San Bernardino County, California. • Many of climate change’s impacts have resulted in greater unpredictability. For example, many regions are projected to experience both too little rain (increasing droughts) and too much rain (in severe events such as rain bombs or atmospheric rivers). Averages tend to obscure these kinds of extremes. Increasingly over the past several years, these kinds of almost stochastic events have increased all over the world. • Projections by their nature tend to assume steady, linear change. Given what has been observed above, this is unlikely on either a local scale or a macrolevel scale. Planners should assume that surprises are likely to occur and plan accordingly. • While overall climate projections have been remarkably accurate in terms of global temperature, many of the impacts of these temperature rises have been faster than expected, in some cases significantly so, with observed phenomena occurring today that researchers expected to see decades later. Planners should assume that impacts will occur on shorter time scales than anticipated – acting sooner will save money, time, and effort later.

31 2023 LOCAL HAZARD MITIGATION PLAN
This is important for planners and decision makers to keep in mind. Past conditions are no longer as reliable as guides to future conditions as they once might have been. 3.4 – Overall Probability of Occurrence The overall probability of occurrence of a hazard is indicated by a factor based on likelihood of occurrence: • High – Hazard event is highly likely to occur within 10 years (Probability Factor = 3) • Medium – Hazard event is moderately likely to occur within 10 years. (Probability Factor = 2) • Low – Hazard event is unlikely to occur within 10 years. (Probability Factor = 1) No hazards that have zero probability of occurrence within the next 10 years were included in the Plan. For natural hazards beyond the lifetime of two 5-year updates of the Plan, climate reports and adaptation plans are recommended. The assessment of hazard frequency is based both on past hazard events in the area as well as projected changes in frequency due to climate change under business-as-usual (BAU) scenarios in which the rate of greenhouse gas emissions are not meaningfully reduced.

00.511.522.533.5Extreme HeatPower OutagesDroughtWildfireHazardous MaterialsCyberattackTerrorismEarthquakeInfectious DiseaseFloodHeavy RainSevere WindProbability

32 2023 LOCAL HAZARD MITIGATION PLAN

3.5 – Hazard Profiles 3.5.1 – Extreme Heat Hazard Description Extreme heat refers to a period of abnormally high temperatures in a specific location. There are three major types of extreme heat events: • Extreme heat days, which exceed 98% of all historic high temperatures for the area between April and October from 1961 to 1990. • Warm nights, which exceed 98% of all historic minimum daytime temperatures observed between April and October from 1961 to 1990. • Extreme heat waves, a successive series of extreme heat days and warm nights defined as a minimum of four successive extreme heat days and warm nights by Cal-Adapt. Different regions will experience extreme heat events differently due to variations in historic high temperatures. For example, an extreme heat day on the coast will feel distinct from an extreme heat day in the high desert due to the impact of humidity on people's perception of heat. Humid conditions make a day feel hotter than non-humid conditions, even if the temperature is the same, resulting in a difference known as the heat index. A 90-degree day with 50 percent humidity feels like 95°F, whereas a 90°F day with 90 percent humidity feels like 122°F.

NOAA National Weather Service Heat Index

33 2023 LOCAL HAZARD MITIGATION PLAN
Prolonged exposure to extreme heat can be hazardous to public health, as the human body is less able to withstand high temperatures for extended periods of time. This can result in heat exhaustion and dehydration, which may progress to heat stroke and organ failure if internal body temperature surpasses 105 degrees Fahrenheit. Without intervention, this can be fatal. Location and Extent Extreme heat events occur with the same intensity and duration across all locations in Rialto and are not limited to any specific part of the City. Extreme heat does have disproportionate impacts depending on the type and age of building, however. Many older buildings may not have the same cooling capacity or may be more vulnerable to power outages and loss or air conditioning. The City of Rialto has three identified cooling centers available to the public during extreme heat events: • The Senior Center, 1411 S. Riverside Ave., Rialto, CA 92376 • Carl Johnson Center, 214 N. Palm Ave., Rialto, CA 92376 • The Rialto Library, 251 W. 1st Street, Rialto, CA 92376 Previous Occurrences The NCEI database has recorded five extreme heat events which have occurred within proximity to Rialto over the past 20 years. Year Number 1979 15 1983 3 1987 2 1991 3 1995 2 1999 0 2003 5 2007 14 2011 8 2015 5 2019 3 Annual number of days with a daily maximum temperature above the 95th percentile 1979-2019 Source: https://ephtracking.cdc.gov/Applications/heatTracker/

34 2023 LOCAL HAZARD MITIGATION PLAN
Some specific recent examples include: • 1970s and 1980s Heatwaves: Various heatwaves occurred in the 1970s and 1980s, with several record-breaking high temperatures documented in the San Bernardino area. These events led to concerns about public health and energy use. • 2006 Heat Wave: In July 2006, a significant heatwave affected Southern California, including the San Bernardino area. Temperatures soared well above 100 degrees Fahrenheit, and the extreme heat led to health warnings and increased demand for energy resources. • 2018 Heat Wave: In July 2018, Southern California experienced another notable heatwave, with temperatures in the San Bernardino area reaching extreme levels. The prolonged high temperatures posed health risks and resulted in increased energy consumption for cooling. • 2020 Labor Day Weekend Heat Wave: Over the Labor Day weekend in September 2020, a major heatwave affected the San Bernardino region. Temperatures soared to record highs, prompting heat advisories and concerns about wildfires due to dry conditions. Probability of Future Events and Impacts of Climate Change Overall probability over next ten years: High. The following illustration from NOAA’s Climate Explorer details the probability of days with high temperatures over 95 degrees Fahrenheit to 2100 under multiple emissions scenarios.

35 2023 LOCAL HAZARD MITIGATION PLAN
The probability and frequency of extreme heat events will grow over the coming decades. According to California’s Fourth Climate Assessment for the Los Angeles Region: “The average hottest day of the year is expected to increase roughly 4-7°F under RCP4.5 and 7-10°F under RCP8.5 by the late 21st century. Similar to the spatial pattern in annual max temperature changes, the largest changes in extremes are found in the interior of the region, and particularly the valleys, while the smallest changes are generally confined to coastal regions. The number of extremely hot days is expected to increase in the future. For instance, LA International Airport (LAX) historically experiences less than 15 days per year with temperatures equal to or greater than 90°F (Cayan et al. 2018). By the end of the century under RCP8.5, LAX is projected to experience 50–90 such days per year (Pierce et al. 2018). Sun et al. (2015) similarly found that land locations are projected to experience 60–90 additional extremely hot days (greater than or equal to 95°F) per year by the end of the century, with the exception of the highest elevations and regions along the coast, where increases are only a few days. 3.5.2 – Power Outages Hazard Description A power outage is a temporary loss of electricity to a home or business due to a disruption in the power supply. There are several causes of power outages, including severe weather conditions such as thunderstorms, high winds, and extreme heat. In Southern California, power outages can also be caused by wildfires, earthquakes, and equipment failures. During times of extreme heat, power outages can be particularly hazardous to a city. High temperatures can cause increased demand for electricity as people turn up their air conditioning units, leading to strain on the power grid. This can result in blackouts or brownouts, which can lead to several hazards. Location and Extent Power outages may potentially impact the entirety of the City of Rialto, although areas most prone to power outages are located north of Baseline Road and south of I-10. Electric transmission lines run in these two areas and the area south of Baseline Road is directly exposed to Santa Ana winds through the Cajon Pass.

36 2023 LOCAL HAZARD MITIGATION PLAN
The location and duration of power outages can also vary depending on the cause of the outage. For example, power outages caused by weather events such as thunderstorms or wildfires may be localized, affecting only a few neighborhoods or communities. On the other hand, power outages caused by equipment failures or grid overloads may be more widespread and impact larger areas or even entire regions. Previous Occurrences Minor power outages are a not-infrequent occurrence in any grid system. Several major incidents that impacted the City of Rialto include: • In August 2020, San Bernardino County experienced a widespread power outage that affected more than 20,000 customers across the county, including some in the city of Rialto. The outage was caused by a major equipment failure at a substation operated by Southern California Edison (SCE), the primary utility provider for the region. The outage lasted for several hours, and SCE was able to restore power to most customers by the evening, • In July 2018, a severe thunderstorm caused widespread power outages in San Bernardino County, including the cities of Rialto and Fontana. The storm knocked down power lines and caused equipment failures, leaving thousands of customers without power for several hours. The outage also caused traffic signal outages, which led to significant traffic delays and safety hazards. • In 2011, San Bernardino County experienced a series of power outages caused by a severe windstorm. The storm knocked down power lines and damaged transformers, leading to widespread outages that lasted for several days. Some areas of the county, including parts of Rialto, were without power for up to a week. The above list underlines the vulnerability of the electrical supply for Rialto to natural events such as fire and earthquake, as well as to extreme heat events. One particularly dangerous scenario is a power outage amid a severe heat wave. This scenario, which is likely to result in fatalities, is unfortunately becoming more probable as climate impacts grow. Probability of Future Events and Impacts of Climate Change Overall probability over next ten years: Medium. The likelihood of future power outages impacting the City of Rialto may increase because of climate change and the associated risks of wildfires and extreme heat events.

37 2023 LOCAL HAZARD MITIGATION PLAN
Wildfires have become increasingly common and severe in California beyond the traditional fire season in recent years, with record-breaking fires causing widespread damage and disruption to power infrastructure. Power lines and equipment damaged by wildfires can lead to power outages and disruptions to essential services, such as hospitals and emergency response systems. In addition to the risk of wildfires, extreme heat events associated with climate change can also increase the likelihood of power outages. High temperatures can put strain on the power grid, leading to equipment failures and blackouts. In San Bernardino County, which experiences hot and dry summers, this risk is particularly acute. To mitigate the risks of future power outages, San Bernardino County and utility providers such as Southern California Edison (SCE) have implemented measures such as grid upgrades, equipment maintenance, and emergency response plans. SCE has also implemented Public Safety Power Shutoffs (PSPS) to reduce the risk of wildfire-related power outages. PSPS is a proactive measure in which SCE intentionally shuts off power to certain areas during periods of high fire risk to reduce the risk of equipment-related fires. While these measures can help reduce the risk of power outages, they may not eliminate the risk, especially during extreme weather events. 3.5.3 – Drought Hazard Description A drought is a prolonged period of scarce water supplies caused by a lack of substantial rainfall. By one count, there are over 150 definitions for “drought”. The National Weather Service describes drought as “a deficiency of moisture that results in adverse impacts on people, animals, or vegetation over a sizeable area.” Drought is a natural occurrence in all climates, both in regions with high and low average rainfall. Droughts typically are declared when lasting for a calendar season or longer and can be categorized into five different types: meteorological, agricultural, hydrologic, socioeconomic, and ecological. • Meteorological: This type of drought refers to a decrease in rainfall that deviates from the normal precipitation pattern. It includes changes in the amount, intensity, or timing of rainfall, as well as changes in temperature, humidity, and wind patterns. The threshold for defining meteorological drought varies from country to country.

38 2023 LOCAL HAZARD MITIGATION PLAN
In the United States, a meteorological drought is declared if there is less than 2.5mm of rainfall in 48 hours. This type of drought is the first stage to be detected. Broader multi-year precipitation patterns can give rise to drought conditions. In California, the El Niño Southern Oscillation (ENSO) cycle, a regional meteorological event in the Pacific Ocean, is important in the region’s hydrologic regime. The ENSO cycle consists of changes in ocean water and air temperature and results in two phases: El Niño, a warm and wet phase, and La Niña, a dry and cold phase. When La Niña is active, it can lead to below-normal precipitation levels in California and frequently lead to drought conditions. • Agricultural: This type of drought is characterized by insufficient moisture conditions that cause lasting damage to crops and other vegetation. It is dependent on factors such as rainfall, temperature, topography, soil permeability, evapotranspiration, vegetative demand, and more. Agricultural drought begins when the available soil moisture only supports a fraction of the actual evapotranspiration rate. • Hydrological: This type of drought is related to the effects of reduced precipitation on the surface or subsurface water supply. During the latter part of the hydrological cycle, water infiltrates into the groundwater. The subsurface water supply is the last component to return to normal when meteorological conditions and aquifer recharge return to normal. • Socioeconomic: This type of drought occurs when the consequences of drought start to impact social and economic systems. It arises when the demand for an economic good is greater than the available supply due to drought-related weather conditions. Examples of such goods include water, food grains, dairy products, hydroelectric power, and more. Socioeconomic drought affects both individuals and the population as a whole. • Ecological: This type of drought is defined as a widespread and prolonged deficit in naturally available water supplies that leads to multiple stressors across ecosystems. This includes changes in both natural and managed hydrology. Determining the onset and end of a drought can be challenging compared to sudden weather events such as hurricanes, tornadoes, and thunderstorms. Early signs of a drought can be difficult to detect, and it may take some time, perhaps even weeks, or months, before it is recognized. The conclusion of a drought is also challenging to identify for the same reasons. Droughts can range in duration from a few weeks to several years and in some cases, even persist for a decade or more. Drought primes the conditions for a variety of other hazards by drying soil out, which reduces its capacity to absorb water. Thus, when precipitation returns, the soil is less able to hold onto water, increasing runoff and the risk of floods. Due to the soil’s reduced ability to bond together, dry earth is more prone to erosion and landslides. In addition, the lack of

39 2023 LOCAL HAZARD MITIGATION PLAN
participation effects plants and other vegetation in natural places as the lack of nutrients makes them more vulnerable to pests and diseases and the lack of internal water raises the possibility of wildfires. Location and Extent The entirety of the City of Rialto is susceptible to drought. The impact of drought is regional in nature, and typically would extend far beyond the city limits of Rialto to include the whole of southern California. The Palmer Drought Index is a tool used to assess the severity of drought by evaluating the duration and intensity of persistent circulation patterns that cause drought. The intensity of drought in each month is determined by the current weather conditions combined with the cumulative impact of previous months. The effects of drought on water resources such as reservoir levels and groundwater levels take longer to manifest.

US Drought Monitor Classification Scheme. Source: http://drought.monitor.unl.edu/AboutUSDM/Droughtclassification.aspx Previous Occurrences Rialto, like the rest of California, has experienced many drought events throughout its history. California was in some form of drought for 376 consecutive weeks from December 20, 2011, until March 14, 2017. By summer of 2014, almost all of California was experiencing level D2 (severe drought) conditions. By 2015, emergency water-saving mandates were enacted, which required all jurisdictions to reduce water use by no less than 25 percent. In late 2016 and early 2017, consecutive occurrences of heavy rain helped end the drought conditions in the state. The following winter, in late 2017 and early 2018, rains did not occur to the same level and slight drought conditions again affected the state. This moderate drought was again abated in the winter season of late 2018 and early 2019, when heavy

40 2023 LOCAL HAZARD MITIGATION PLAN
rains ended any existing drought conditions. Drought conditions returned shortly thereafter, with water restrictions being eased after the intense precipitation events of early 2023.

Probability of Future Events and Impacts of Climate Change Overall probability over next five years: High. Periodic drought has been a fact of life in California since before written records were kept. However, global climate change has already had a significant impact, in part fueling the North American West’s “megadrought”, as of 2023 in its 23rd year and being the driest period in over 1,200 years. October 2019 through September 2022 were California’s driest years on record. Atmospheric rivers (narrow corridors of concentrated moisture in the atmosphere) are largely responsible for precipitation patterns across the southern California region, and coupled with topographical influences, can create intense storms. Cal-Adapt climate projections predict that the likelihood and duration of atmospheric rivers will increase, leading to increased likelihoods of flood events. Predictions for extreme weather events show that no major trend changes are expected under either scenario. However, as noted above for patterns in precipitation, whiplash events are expected to increase. When years with elevated numbers of extreme rain events follow dry years, the likelihood and severity of mudslides and flooding increases. This is largely due to reductions in vegetation during dry years, which otherwise stabilize soil. Conversely, dry years that follow upticks in extreme rain events can lead to wildfires. This is due to increased presence of fuel sources for wildfire in the form of dry vegetation.

41 2023 LOCAL HAZARD MITIGATION PLAN
These whiplash events will increase vulnerability to both fire and floods. A tragic example is the Hawai’i fires on the island of Maui that consumed the historic royal capital of Lahaina, killing large numbers of people. The compounding nature of this disaster – high winds driving fires on an island experiencing extended drought conditions – illustrates that drought is not only an absence of water but can be an accelerant for devastating wildfires. According to California’s Fourth Climate Change Assessment’s Los Angeles Region survey, published in 2019: Anthropogenic warming has increased the probability that low-precipitation years coincide with warm years, increasing the current risk and severity of droughts and low snowpack in California (Difenbaugh et al. 2015; Berg and Hall 2017; Williams et al. 2015). Atmospheric conditions conducive to California droughts, such as a persistent region of high pressure in the northeastern Pacific Ocean, may have also become more frequent in recent decades (Swain et al. 2016). GCMs (global climate models) project significantly drier soils in the future over the Southwest (including California), with more than an 80% chance of a multidecadal drought during 2050–2099 under RCP8.5 (Cook et al. 2015). The effects of climate change on drought are expected to be mixed. For Instance, in some years, climate change-enhanced weather patterns such as those during the El Nino Southern Oscillation (ENSO) phase may bring more rainfall to California and Rialto, alleviating drought conditions. On the other hand, it may also extend the La Niña phase of ENSO, leading to longer periods without precipitation. Furthermore, climate change is projected to cause more frequent and prolonged heat waves in California, increasing the average temperature. During such events, the water supply may be diverted for essential cooling needs, including those of the elderly and to maintain critical City operations, leading to greater water consumption. If a heat wave were to occur during a drought, it would place even more strain on the water supply. From a larger perspective, rising temperatures in California are expected to impact and reduce water supplies across the state. Much of California's water comes from snowmelt in the High Sierra, a part of the Sierra Nevada mountain range. As temperatures rise due to climate change, the precipitation that would have fallen as snow is expected to become rainfall, leading to less snowfall and therefore, less meltwater from the Sierra Nevada snowpack, reducing the water that would have flowed into Southern California's reservoirs and aqueducts. 3.5.4 – Wildfire Hazard Description

42 2023 LOCAL HAZARD MITIGATION PLAN
Wildfires tend to occur most frequently in the summer when dry brush provides fuel for flames to spread rapidly. Ignition sources for wildfires can include campfires that were not properly extinguished, discarded cigarettes, burning debris, lightning strikes, or intentional acts of arson. Wildfires can start as slow burns along the forest floor, damaging and killing trees. As they spread to the tops of trees, wind can carry the flames from one tree to another, causing the fire to spread more rapidly. Typically, the first indication of a wildfire is the presence of dense smoke. Wildfires pose a significant threat when they happen during a drought, and they can occur anywhere, with variation in size, intensity, location, and duration. The danger to people and property is particularly high in the wildland urban interface (WUI), where development meets undeveloped open grassland or fire-adapted forest ecosystems. Wildfires are more frequent and intense in summer and autumn, especially during droughts when dry vegetation such as fallen branches, leaves, grasses, and scrub become highly flammable. Some experts attribute the increased severity and frequency of wildfires to global warming, which is believed to worsen drought conditions. As urbanization expands into wildlands, fires sometimes destroy suburban homes in the WUI. Entire neighborhoods or even towns can be at risk, as illustrated by the destruction of Paradise, California in 2018, Lytton, British Columbia in 2021, and nearly 1,000 homes near Boulder, Colorado in December 2021. Strong winds and low humidity exacerbate the threat to people and property, and fires can also start in urban areas and spread into wildlands, caused by various sources such as electrical fires, arson, cooking, smoking, and other hazards. Location and Extent The northern sections of Rialto are at very high risk for wildland fires, which have the potential to threaten life and property. Fires occur nearly every dry season, occasionally approaching N Riverside Avenue in the north of Rialto and sometimes threatening to cross that road into residential neighborhoods. In October 2003, a portion of north Rialto was threatened by the Grand Prix Fire that affected parts of Fontana, Rancho Cucamonga, Upland, Claremont, as well as parts of National Forests. The fire spread through wild land area that borders a residential area but was stopped by fire personnel before impacting structures.

43 2023 LOCAL HAZARD MITIGATION PLAN

Source: https://calfire-forestry.maps.arcgis.com/apps/webappviewer/index.html?id=4466cf1d2b9947bea1d4269997e86553 (data updated November 21, 2022)

44 2023 LOCAL HAZARD MITIGATION PLAN
Map of CAL FIRE’s Fire Hazard Severity Zones in Local Responsibility Areas – Rialto (https://osfm.fire.ca.gov/media/5950/rialto.pdf)

45 2023 LOCAL HAZARD MITIGATION PLAN
Fire Danger Rating System Fire Danger Rating Description Low (L) Fuels do not ignite readily from small firebrands, although a more intense heat source, such as lightning, may start fires in duff or punky wood. Fires in open cured grasslands may burn freely a few hours after rain, but woods fires spread slowly by creeping or smoldering, and burn in irregular fingers. There is little danger of spotting.

Moderate (M)
Fires can start from most accidental causes, but except for lightning fires in some areas, the number of starts is generally low. Fires in open cured grasslands will burn briskly and spread rapidly on windy days. Timber fires spread slowly to moderately fast. The average fire is of moderate intensity, although heavy concentrations of fuel, especially draped fuel, may burn hot. Short-distance spotting may occur but is not persistent. Fires are not likely to become serious and control is relatively easy.

High (H) All fine dead fuels ignite readily, and fires start easily from most causes. Unattended brush and campfires are likely to escape. Fires spread rapidly and short-distance spotting is common. High intensity burning may develop on slopes or in concentrations of fine fuels. Fires may become serious and their control difficult unless they are attacked successfully while small. Very High (VH) Fires start easily from all causes and, immediately after ignition, spread rapidly and increase quickly in intensity. Spot fires are a constant danger. Fires burning in light fuels may quickly develop high intensity characteristics, such as long-distance spotting and fire whirlwinds when they burn into heavier fuels.

Extreme (E)
Fires start quickly, spread furiously, and burn intensely. All fires are potentially serious. Development into high intensity burning will usually be faster and occur from smaller fires than in the very high fire danger class. Direct attack is rarely possible and may be dangerous except immediately after ignition. Fires that develop headway in heavy slash or in conifer stands may be unmanageable while the extreme burning condition lasts. Under these conditions the only effective and safe control action is on the flanks until the weather changes, or the fuel supply lessens. U.S. Forest Service’s Wildland Fire Assessment System (USFS WFAS)

46 2023 LOCAL HAZARD MITIGATION PLAN
Previous Occurrences FEMA Declaration String State Fiscal Year Declared Incident Type Incident Subcategory County FM-5325-CA CA 2020 Fire Apple Fire San Bernardino (County) FM-5147-CA CA 2016 Fire Blue Cut Fire San Bernardino (County) FM-5381-CA CA 2021 Fire Blue Ridge Fire San Bernardino (County) FM-2425-CA CA 2002 Fire Bluecut Fire San Bernardino (County) DR-635-CA CA 1981 Fire Brush & Timber Fires San Bernardino (County) FM-2728-CA CA 2007 Fire Butler 2 Fire San Bernardino (County) FM-2497-CA CA 2003 Fire Ca-Bridge Fire-09-05-2003 San Bernardino (County) FM-2501-CA CA 2004 Fire Ca-Grand Prix Fire-10-23-2003 San Bernardino (County) FM-2491-CA CA 2003 Fire Ca-Locust Wildfire-08-19-2003 San Bernardino (County) EM-3140-CA CA 1999 Fire Ca-Wildfires-08/25/1999 San Bernardino (County) FM-5350-CA CA 2020 Fire El Dorado Fire San Bernardino (County)

47 2023 LOCAL HAZARD MITIGATION PLAN
DR-872-CA CA 1990 Fire Fires San Bernardino (County) DR-1005-CA CA 1994 Fire Fires, Mud/Landslides, Flooding, Soil Erosion San Bernardino (County) DR-295-CA CA 1970 Fire Forest & Brush Fires San Bernardino (County) FM-2792-CA CA 2009 Fire Freeway Fire Complex San Bernardino (County) FM-2738-CA CA 2008 Fire Grass Valley Fire San Bernardino (County) FM-2955-CA CA 2011 Fire Hill Fire San Bernardino (County) FM-5301-CA CA 2020 Fire Hillside Fire San Bernardino (County) FM-2433-CA CA 2002 Fire Louisiana Fire San Bernardino (County) FM-5089-CA CA 2015 Fire North Fire San Bernardino (County) FM-2833-CA CA 2009 Fire Oak Glen Fire San Bernardino (County) FM-2503-CA CA 2004 Fire Old Fire San Bernardino (County) FM-2836-CA CA 2009 Fire Pendleton Fire San Bernardino (County) FM-5144-CA CA 2016 Fire Pilot Fire San Bernardino (County)

48 2023 LOCAL HAZARD MITIGATION PLAN
FM-2653-CA CA 2006 Fire Sawtooth Fire Complex San Bernardino (County) FM-2841-CA CA 2010 Fire Sheep Fire San Bernardino (County) EM-3279-CA CA 2008 Fire Wildfires San Bernardino (County) DR-4569-CA CA 2021 Fire Wildfires San Bernardino (County) DR-1731-CA CA 2008 Fire Wildfires, Flooding, Mud Flows, And Debris Flows San Bernardino (County) DR-1498-CA CA 2004 Fire Wildfires, Flooding, Mudflow And Debris Flow Directly Related T San Bernardino (County)
FM-2464-CA CA 2002 Fire Williams Fire San Bernardino (County) Large fires have been part of the Southern California landscape for millennia. Indigenous communities used controlled fires to shape the landscape to their benefit. In the aftermath of Mexican and later American colonization, California’s fire regime was significantly altered. Early US forest management practices centered around the idea of fire suppression, which reduced the frequency of fires in proximity to settlements but ultimately increased their intensity by allowing vegetation to build up and fuel more intense fires. The following image from Capital Public Radio uses Cal Fire data to illustrate wildfire color-coded by decade since the 1970s. Rialto’s main vulnerability to fire is on the very north side of the city near North Riverside Avenue.

49 2023 LOCAL HAZARD MITIGATION PLAN

(https://projects.capradio.org/california-fire-history) Probability of Future Events and Impacts of Climate Change Likelihood of occurrence in the next ten years: High. Wildfires can occur at any time of the year, although over the past two decades, wildfire season has begun to extend into the cooler months. Housing is being developed currently on the site of a former golf course in the north of Rialto. An existing northern neighborhood is under consideration for annexation by the City. Both additions, while boosting the city’s tax base, will also raise the city’s fire risk by putting more housing in closer proximity to areas susceptible to wildfire. The frequency and severity of fires are increasing due to higher temperatures and dryer climates. Climate change is projected to lead to increased temperatures and more frequent/intense droughts, resulting in more dry plant matter available as fuel and a higher risk of wildfires statewide.

50 2023 LOCAL HAZARD MITIGATION PLAN
According to California’s Fourth Climate Assessment: Future projections by Jin et al. (2015) using statistical models indicate that southern California may experience a larger number of wildfires and burned area by the mid-21st century under RCP8.5. Overall burned area is projected to increase over 60% for Santa Ana-based fires and over 75% for non-Santa Ana fires. New wildfire projections were developed for the Assessment (Westerling et al. 2018) using different statistical models than those used by Jin et al. (2015), which also incorporated new datasets of future climate data and land use. Compared to the observed 1950- 2009 historical average area burned of 53,300 hectares (Jin et al. 2015), the modeled 1976-2005 historical average area burned is roughly 16,000 hectares (Westerling et al. 2018). This discrepancy highlights that large uncertainties remain in current wildfire models and is an area where further research is required. Based on the projections developed by Westerling et al. (2018), the annual burned area over the LA region may increase over 2000 hectares by the mid-21st century under RCP4.5 or RCP8.5 compared to simulated historical conditions. Similar, yet potentially slightly lower, increases are projected by the late-21st century, as continued warming (even with moderate precipitation increases) could lead to overall fuel declines necessary for wildfire. And in August 2023, Nature published “Climate warming increases extreme daily wildfire growth risk in California” (https://www.nature.com/articles/s41586-023-06444-3.epdf) that further attempted to quantify future wildfire risk. Brown et al. conclude that as of the time of publication (August 2023), aggregate expected frequency of extreme wildfire events has grown by 25% over pre-industrial conditions. Under lower emissions scenarios, the aggregate expected frequency of extreme wildfire events more than doubles from today to 59% relative to pre-industrial conditions, and under very high-emissions scenarios increases by 172%. 3.5.5 – Hazardous Materials Hazard Description Hazardous materials are substances that have physical properties that can be dangerous to human health or the environment if they are not handled or managed correctly. They can come in the form of pesticides, herbicides, toxic metals, chemicals, liquefied natural gas, explosives, volatile chemicals, and radioactive materials. These substances can be found in both households and businesses, such as motor oil, paint, cleaners, solvents, gasoline, and lawn and garden chemicals.

51 2023 LOCAL HAZARD MITIGATION PLAN
If hazardous materials are mishandled or improperly managed, they can contaminate soil and groundwater, which can pose a threat to the health of individuals and ecological systems. When contaminated sites are disturbed, the public can be exposed to toxic substances through airborne dust, surface water runoff, or vapors. The following bullets define hazardous materials according to the Occupational Safety and Health Administration (OSHA): • Chemicals that are carcinogens, toxic agents, irritants, or corrosives and sensitizers. • Agents that act on the hematopoietic system. • Agents which damage the lungs, skin, eyes, or mucous membranes. • Chemicals that are combustible, explosive, flammable, oxidizers, pyrophoric, unstable, reactive, or water reactive. • Chemicals that may produce or release dust, gases, fumes, vapors, mists, or smoke with any of the previously mentioned characteristics during normal handling, use, or storage. The nine classes of hazardous materials are provided below. Hazard Class 1. Explosives 1.1: Mass Explosion 1.2: Projectile Hazard 1.3: Minor blast/projectile/fire 1.4: Minor blast 1.5: Insensitive explosives 1.6: Very insensitive explosives 2. Compressed Gases 2.1: Flammable Gases 2.2: Nonflammable compressed 2.3: Poisonous 3. Flammable Liquid 3.1: Flammable (flash point below 141°) 3.2: Combustible (flash point 141°-200°) 4. Flammable Solids 4.1: Flammable solids 4.2: Spontaneously combustible 4.3: Dangerous when wet 5. Oxidizers and Organic Peroxides 5.1: Oxidizer 5.2: Organic Peroxide

52 2023 LOCAL HAZARD MITIGATION PLAN

6. Toxic Materials 6.1: Material that is poisonous 6.2: Infectious Agents 7. Radioactive Material 7.1: Radioactive I 7.2: Radioactive II 7.3: Radioactive III 8. Corrosive 8.1: Destruction of the human skin 8.2: Corrode steel at a rate of 0.25 inches per year 9. Miscellaneous A material that presents a hazard during shipment but does not meet the definition of other classes Source: Occupational Safety and Health Administration (OSHA) Location and Extent A major hazardous materials site in Rialto is the BKK Landfill. This landfill was used to dispose of hazardous waste for many years, and it is now a Superfund site due to the contamination of soil and groundwater. In addition, there are numerous other locations throughout Rialto where hazardous materials are stored or used. For example, there are many industrial facilities in the southern part of the City that use chemicals or other hazardous materials in their processes. These facilities are required to comply with regulations related to the storage, handling, and disposal of these materials to minimize the risk of exposure to workers and the surrounding community. There are also transportation routes that carry hazardous materials through Rialto. These may include pipelines, railroads, and highways. Accidents or spills involving hazardous materials during transport could pose a significant risk to public health and the environment. One notable pipeline is the Calnev Pipeline, operated by Kinder Morgan. The pipeline traverses the city of Rialto, and has a terminal stop in the neighboring city of Colton. The Calnev Pipeline is a is a 550-mile long buried refined oil products pipeline, consisting of two parallel lines, one with a diameter of 14 inches (360 mm) and one with a diameter of 8 inches (200 mm). The lines carry gasoline, jet fuel and diesel fuel from Los Angeles as far as Nellis Air Force Base near Las Vegas, Nevada. It carries approximately 128,000 barrels per day (20,400 m3/d).

53 2023 LOCAL HAZARD MITIGATION PLAN
Previous Occurrences There have been several hazardous materials incidents in the City of Rialto over the years. Here are some notable examples: • In 2012, a chemical spill occurred at a Rialto factory. A tank containing nitric acid and hydrofluoric acid leaked, causing a chemical reaction, and releasing a cloud of gas. Two workers were injured, and several others had to be decontaminated. • In 2008, a train carrying hazardous materials derailed in Rialto. The train was carrying hydrochloric acid and sodium hydroxide, among other chemicals. Some of the chemicals spilled, and a nearby neighborhood was evacuated as a precaution. • In 2002, a major explosion occurred at a fireworks factory in Rialto. The explosion was so powerful that it shattered windows up to a mile away. Two workers were killed, and several others were injured. • In 1999, a fire broke out at a hazardous waste facility in Rialto. The fire burned for several days, releasing toxic smoke into the air. The facility was eventually declared a Superfund site. Also of note, while not within Rialto city limits, in 1989 the Calnev Pipeline ruptured in a San Bernardino neighborhood due to damage from the cleanup of a train derailment, that occurred thirteen days earlier. The resulting gasoline fire killed two people and destroyed eleven homes. Probability of Future Events and Impacts of Climate Change Likelihood of occurrence in the next ten years: Low. The probability of such events can vary depending on a variety of factors, such as the type and quantity of hazardous materials present in the area, the condition of storage and transportation facilities, and the effectiveness of safety protocols and emergency response plans. In Rialto, there are several known hazardous materials sites and storage areas, including several facilities that store or transport chemicals and other potentially dangerous substances. These facilities are subject to regulatory oversight and are required to maintain appropriate safety protocols to minimize the risk of accidents and spills. However, as with any human activity, accidents can still occur. Natural disasters such as earthquakes or floods can also increase the risk of hazardous materials events by damaging storage and transportation facilities or disrupting transportation routes.

54 2023 LOCAL HAZARD MITIGATION PLAN
Climate change may also impact the probability of hazardous materials events in the future. For example, rising temperatures and more frequent extreme weather events may increase the risk of chemical spills and explosions due to equipment failure or human error. Vulnerability and Impact The incident outcomes and extent vary depending on the incident size, exposure to nearby structures and people, and the assets required for cleanup. The quantity of material released into the air determines the number of people potentially affected, with larger quantities affecting a larger area and vice versa. Natural weather conditions such as wind and rain can either hinder or foster the aerial spread of hazardous materials. Individuals Hazardous materials events, such as spills, leaks, or releases of toxic chemicals, can have significant impacts on the health and safety of people. These events can result in exposure to harmful chemicals, which can cause immediate health effects, such as skin and eye irritation, respiratory problems, and nausea. Long-term exposure to certain hazardous materials can also increase the risk of cancer and other chronic health problems. The population with property situated within a half-mile radius of a hazardous material incident is at the highest risk of exposure. Similarly, first responders face potential risks during the containment of the spill, but their exposure is limited by using personal protective equipment (PPE) and implementing other safety measures such as maintaining a safe distance and using shields. People who are most vulnerable to the impacts of hazardous materials events include children, pregnant women, the elderly, and people with pre-existing health conditions. Exposure to hazardous materials can also disproportionately impact low-income and minority communities who may be located closer to hazardous materials storage sites and may have limited access to healthcare resources. Transportation systems can be affected by hazardous material incidents, particularly for the population and community assets located within a half-mile on either side of railroads or highways. Heavy trucks carrying hazardous chemicals on state routes and freeways pose significant risks to areas and populations located within a half-mile of the highway system. Vulnerable areas and populations can be more precisely determined by atmospheric conditions, wind direction and velocity, and the type of chemical involved.

55 2023 LOCAL HAZARD MITIGATION PLAN
In addition to health impacts, hazardous materials events can also have economic impacts, such as property damage and loss of business revenue. The cleanup and remediation of hazardous materials sites can also be costly and time-consuming. Freeway/Transportation If a hazardous materials incident occurs on a freeway, it could cause significant traffic congestion as emergency response crews work to contain the incident and clean up the area. The affected section of the freeway would need to be closed until the hazardous materials have been removed and the area deemed safe for travel. Similarly, if a hazardous materials release occurs near a rail line, the rail line could be shut down until the hazardous materials have been removed and the area deemed safe for trains to pass through. This could disrupt the transportation of goods through the area and have economic impacts on local businesses that rely on rail transportation for their operations. If a hazardous materials incident occurs on or near a transportation route, it could have impacts on the air quality in the surrounding area. Hazardous materials releases can release toxic fumes into the air, which could pose health risks to people living or working in the area. Utilities The City of Rialto's streets house pipelines that are owned and operated by multiple companies. In the event of a pipeline rupture, there is a significant risk to the safety of individuals, property, and the environment. Past incidents of pipeline ruptures at various locations in the region suggest that the community will remain vulnerable to such dangers in the future. Hazardous material spills can have severe impacts on the city's stormwater, wastewater, and water systems. Following a spill, the immediate aftermath can lead to contamination of the city's stormwater system, with the material spreading until the spill is contained. Hazmat transport via rail or road can also lead to corrosion or damage of the transport surfaces. Depending on the type and quantity of material released, air quality can be poor or even dangerous, with the material potentially spreading across the jurisdiction and into neighboring communities. Additionally, responders are at risk if there is a large amount of material stored on-site, with many locations having nearby fuel tanks to keep responder vehicles ready to go.

56 2023 LOCAL HAZARD MITIGATION PLAN

3.5.6 – Cyberattack Hazard Description A cyberattack is a malicious attempt to damage, disrupt, or gain unauthorized access to a computer system, network, or device. These attacks can take many forms and can be launched from anywhere in the world, making them a constant threat to local governments and businesses alike. Cyberattacks on local governments and businesses are becoming increasingly common as more services move online and more data is stored in digital formats. These attacks can take many forms, including phishing scams, ransomware attacks, and distributed denial-of-service (DDoS) attacks. In a phishing scam, an attacker will send a legitimate-looking email or message to a target, attempting to trick them into revealing sensitive information such as usernames and passwords. In a ransomware attack, an attacker will use malware to encrypt a victim's data, demanding payment in exchange for the decryption key. In a DDoS attack, an attacker will flood a website or server with traffic, overwhelming it and making it unavailable to legitimate users. Cyberattacks on local governments can be particularly damaging, as they can disrupt critical services such as emergency response systems, public utilities, and transportation networks. They can also result in the theft of sensitive data such as personal information, financial data, and intellectual property. Businesses are also vulnerable to cyberattacks, which can result in significant financial losses, reputational damage, and legal liability. Location and Extent By its nature, the threat of cyberattacks is ever-changing, and as the mechanics of how work happens is increasingly digitized, is ever-growing as well. Increasing vulnerability of cloud-based systems may result in attempts to wall off certain portions of the cloud or even create “mini-clouds”. Widely available artificial intelligence (AI) is likely to increase vulnerability to cyberattacks as it becomes more pervasive and supplements or replaces human-based knowledge. Cyberattacks are generally not geographically based in the sense that there is a discrete, singular location that is targeted. They could be targeted to specific organizations or departments or targeted towards the entire municipal IT network. Cloud storage, for example, may be used by a city but may physically be distributed among many servers in various locations, some potentially far from the City.

57 2023 LOCAL HAZARD MITIGATION PLAN
Previous Occurrences Cyberattacks are often not publicized, and as such, there is not a detailed record of cyberattacks potentially available to the public against Rialto city government or local businesses. However, there have been several high-profile cyberattacks that illustrate the nature of the threat: • Atlanta Ransomware Attack (2018): In March 2018, the city of Atlanta, Georgia, fell victim to a ransomware attack. The SamSam ransomware was used to infect the city's computer systems, leading to widespread disruptions in various services, including the court system, utility payments, and police services. The attackers demanded a ransom in Bitcoin to decrypt the affected systems. The incident highlighted the vulnerabilities of municipal IT infrastructure and the potential consequences of cyberattacks on essential services. • Baltimore Ransomware Attack (2019): In May 2019, the city of Baltimore, Maryland, was hit by a ransomware attack using the RobbinHood ransomware. The attack crippled the city's computer systems, affecting services such as email, payment processing, and even real estate transactions. The city refused to pay the ransom, leading to a lengthy recovery process that lasted several weeks and cost millions of dollars. • New Orleans Cyberattack (2019): In December 2019, the city of New Orleans, Louisiana, suffered a cyberattack that disrupted various city services. While the city stated that no ransom was paid, the attack affected emergency services, public safety operations, and various administrative functions. This incident highlighted the potential risks of cyberattacks on critical infrastructure and the need for preparedness and response measures. • Colonial Pipeline Ransomware Attack (2021): Although not targeting a municipal government directly, the Colonial Pipeline ransomware attack in May 2021 had significant regional implications. The Colonial Pipeline, which transports a large portion of the East Coast's fuel supply, was shut down due to a ransomware attack. The pipeline's shutdown led to fuel shortages and price increases in various states, affecting multiple municipalities' ability to provide services and respond to emergencies. Probability of Future Events Overall probability over next ten years: High.

58 2023 LOCAL HAZARD MITIGATION PLAN
The probability of future cyberattacks has only grown, and is likely to continue growing, as malicious actors gain access to increasingly sophisticated tools. Check Point Research in 2022 reported that: • Global volume of cyberattacks reached an all-time high in Q4 of 2022 with an average of 1168 weekly attacks per organization. • The top 3 most attacked industries in 2022 were Education/Research, Government and Healthcare. • Africa experienced the highest volume of attacks with 1875 weekly attacks per organization, followed by Asia/Pacific with 1691 weekly attacks per organization. • North America (+52%), Latin America (+29%) and Europe (+26%) showed largest increases in cyberattacks in 2022, compared to 2021. • USA saw a 57% increase in overall cyberattacks in 2022, UK saw a 77% increase and Singapore saw a 26% increase. This was driven in part by the increase in remote work and collaboration environments such as Slack, as well as the introduction of rudimentary artificial intelligence systems such as ChatGPT which made the deployment of cyberattack methods much quicker. 3.5.7 – Terrorism Hazard Description Terrorism is defined as the use of violence and intimidation in the pursuit of political, ideological, or religious aims. Terrorism can take many forms, but generally involves attacks or threats that are intended to cause harm, fear, or disruption to the community. Here are some examples of the types of terrorism that could impact an American city (cyberattacks are described in the preceding section): • Domestic Terrorism: Domestic terrorism refers to acts of violence committed by individuals or groups based in the United States who seek to promote a political or social agenda. Domestic terrorism can take many forms, including hate crimes, extremist attacks, and targeted violence. • International Terrorism: International terrorism refers to acts of violence committed by individuals or groups who are based outside of the United States and seek to cause harm to American interests. International terrorism can include attacks on American citizens, businesses, or institutions, as well as attacks on foreign targets that have an impact on American interests. • Biological Terrorism: Biological terrorism refers to the intentional release of

59 2023 LOCAL HAZARD MITIGATION PLAN
biological agents, such as viruses or bacteria, with the intention of causing harm to the public. Biological terrorism can cause widespread illness or death, as well as panic and fear within the community. • Chemical Terrorism: Chemical terrorism refers to the intentional release of chemical agents with the intention of causing harm to the public. Chemical terrorism can cause widespread illness or death, as well as damage to infrastructure and the environment. Location and Extent As with any American city, terrorism could impact various areas of Rialto depending on the type and scale of the attack. Certain areas are more likely to attract terrorist attack, and mass shooting events would be more likely in areas with higher concentrations of people. Previous Occurrences There have been no known instances of terrorism in Rialto, CA. However, there have been some incidents of mass shootings in San Bernardino County, where Rialto is located: • In 2015, a mass shooting occurred at the Inland Regional Center in San Bernardino, which is approximately 20 miles from Rialto. The shooting resulted in 14 deaths and 22 injuries. • In 2017, a mass shooting occurred at North Park Elementary School in San Bernardino, which is approximately 12 miles from Rialto. The shooting resulted in the deaths of a teacher and a student and the injury of another student. While these incidents did not occur directly in Rialto, they had a significant impact on the wider San Bernardino County community and serve as a reminder of the potential threat of violence in public spaces. Probability of Future Events and Impacts of Climate Change Likelihood of occurrence in the next ten years: Low. It is difficult to predict the probability of future terrorist or mass shooting-related events in San Bernardino County or any other location. While there is no way to eliminate the risk of such events, law enforcement and emergency services can take proactive measures to prevent and respond to potential threats.

60 2023 LOCAL HAZARD MITIGATION PLAN
It is worth noting that the number of mass shootings and terrorist attacks in the United States has increased over the past several years. However, it is important to consider that this increase may be due, in part, to changes in reporting and data collection methods, as well as a broader societal shift toward awareness of and attention to such events. 3.5.8 – Earthquake Hazard Description An earthquake is a sudden, violent movement of the earth's surface that is caused by volcanic activity or tectonic movement along fault lines and the subsequent release of energy in the form of seismic waves. The effects of an earthquake can be widespread and include surface faulting, shaking of the ground, landslides, soil liquefaction, changes in the earth's tectonic structure, tsunamis, and oscillations in large bodies of water. The point where two tectonic plates meet is called a fault line, and earthquakes often occur along these lines. In California, the San Andreas Fault is the most well-known fault line, where the North American Plate and the Pacific Plate come together. Over time, the constant friction between these two plates has caused the intersection to break into smaller faults, making the area more prone to earthquakes. The Earth's surface may show visible signs of fault lines in the form of sudden changes or breaks in the landscape. Earthquakes strike suddenly, without warning. Earthquakes can occur at any time of the year and at any time of the day or night. On a yearly basis, 70 to 75 damaging earthquakes occur throughout the world. The two main types of earthquakes that can occur in each region are strike-slip and dip-slip earthquakes. Strike-slip earthquakes occur on vertical or nearly vertical faults, where the plates of the Earth's crust move mostly horizontally. The direction of movement across the fault determines if it is a right lateral fault or a left lateral fault. Dip-slip earthquakes occur on slanted faults where the blocks of the Earth's crust shift mostly vertically. If the Earth above the fault moves downward, it is called a normal fault, and if it moves upward, it is known as a reverse fault. If the reverse fault has a dip of 45 degrees or less, it is referred to as a thrust fault. The region close to a fault line is vulnerable to damage due to the possibility of a fault rupture, resulting in the shifting and displacement of the land on either side of the fault, which may move a few inches to several feet in opposite directions. Buildings and infrastructure near, on top of, or crossing a fault line may be severely damaged or even

61 2023 LOCAL HAZARD MITIGATION PLAN
destroyed. Some faults have only recently formed in geological history and are known as Quaternary faults. These faults, which have developed within the past 1.8 million years, are a concern as they are most likely to be active and cause future earthquakes. The Alquist-Priolo Earthquake Fault Zoning Act permits the California State Geologist to identify zones around active faults as Alquist-Priolo Special Study Zones, which are designated as special regulatory areas. These zones require further study to determine the location of the fault and the extent of the area prohibited from surface construction above the known location of an active fault. Liquefaction Liquefaction happens when seismic energy shakes an area with a low-density material, such as fine-grained soil like sand or silt, that is saturated with water. This can cause the loose soil to suddenly compact and behave more like a liquid than solid ground. Buildings and infrastructure built on these areas can be damaged or even collapse because of the liquefaction. Utility lines like pipelines that pass through a liquefaction zone may also be ruptured, leading to potential flooding or the release of hazardous substances. Although there is no standard method for measuring the scale of liquefaction, other factors can be used to gauge the extent of damage caused by it. These include the type of soil, the strength of the seismic shaking in the affected area, the size of the affected region, and the degree of destruction caused by the liquefaction. Seismic shaking Seismic shaking is the trembling felt on the Earth's surface caused by an earthquake. While not all earthquakes are strong enough to cause noticeable shaking, the intensity of seismic shaking is proportional to the amount of energy released from the earthquake, which is determined by the length and depth of the fault that caused it. Typically, areas closest to the fault rupture experience stronger seismic shaking, while areas farther away experience weaker shaking. Seismic shaking can result in structural damage or collapse, and it can also harm underground utilities or pipelines, leading to the release of hazardous materials or flooding if water lines are broken.

62 2023 LOCAL HAZARD MITIGATION PLAN
Earthquake Shaking Potential for California Source: https://www.conservation.ca.gov/cgs/shakemaps The Richter magnitude scale, named after seismologist Charles F. Richter, measures the amount of energy released by an earthquake at its source. The scale ranges from 0 to 10, with each increase of one representing an earthquake 10 times stronger than the previous one. However, because it is a logarithmic scale, the energy released increases by a factor of 32 for each one-point increase in magnitude. For example, an earthquake with a magnitude of 6.0 releases 32 times more energy than an earthquake with a magnitude of 5.0. The Mercalli intensity scale, on the other hand, measures the effects of an earthquake on people, structures, and the environment. It is based on observations of damage and shaking intensity rather than on instrumental measurements. The scale ranges from I to XII, with each level representing a different level of damage and impact. For example, an earthquake with an intensity of I would be felt only by a few people under very special circumstances, while an earthquake with an intensity of XII would cause total destruction of buildings and infrastructure.

63 2023 LOCAL HAZARD MITIGATION PLAN
The Richter Magnitude Scale Richter Magnitudes Earthquake Effects Less than 3.5 Generally, not felt but recorded. 3.5-5.4 Often felt, but rarely causes damage. Under 6.0 At most slight damage to well-designed buildings. Can cause major damage to poorly constructed buildings over small regions. 6.1-6.9 Can be destructive in areas up to about 100 kilometers across where people live. 7.0-7.9 Major earthquake. Can cause serious damage over larger areas. 8 or greater Great earthquake. Can cause serious damage in areas several hundred kilometers across. Source: https://www.usgs.gov/natural-hazards/earthquake Modified Mercalli Intensity Scale for Earthquakes Scale Intensity Description of Effects Corresponding Richter Scale Magnitude I Instrumental Detected only on seismographs II Feeble Some people feel it <4.2 III Slight Felt by people resting; like a truck rumbling by IV Moderate Felt by people walking V Slightly Strong Sleepers awake; church bells ring <4.8 VI Strong Trees sway: suspended objects swing, objects fall off shelves <5.4 VII Very Strong Mild Alarm; walls crack; plaster falls <6.1

64 2023 LOCAL HAZARD MITIGATION PLAN
VIII Destructive Moving cars uncontrollable; masonry fractures; poorly constructed buildings damaged.

IX Ruinous Some houses collapse; ground cracks; pipes break open <6.9 X Disastrous Ground cracks profusely; many buildings destroyed; liquefaction and landslides widespread <7.3 XI Very Disastrous Most buildings and bridges collapse; roads, railways, pipes, and cables destroyed XII Catastrophic Total destruction: trees fall; ground rises and falls in waves >8.1 Source: https://www.usgs.gov/natural-hazards/earthquake Location and Extent

65 2023 LOCAL HAZARD MITIGATION PLAN
The entirety of the city of Rialto may be impacted by earthquakes, with areas closer to faults likely to experience more severe impacts. Major faults in the vicinity of Rialto include: • San Andreas Fault: The San Andreas Fault is a major fault that runs approximately 800 miles through California. The fault marks the boundary between the Pacific Plate and the North American Plate and is responsible for some of the largest earthquakes in California history. The fault runs just to the east of Rialto, and seismic activity along this fault could have significant impacts on the city. • San Jacinto Fault: The San Jacinto Fault is a major fault that runs through southern California, with a length of approximately 150 miles. The fault runs just to the south of Rialto and can generate earthquakes with a magnitude of up to 7.5. • Cucamonga Fault: The Cucamonga Fault is a minor fault that runs through the San Bernardino Mountains, with a length of approximately 30 miles. The fault runs just to the north of Rialto and can generate earthquakes with a magnitude of up to 6.0. Fontana Seismic Zone: The Fontana Seismic Zone is a region of seismic activity that runs through San Bernardino County, just to the west of Rialto. The zone is characterized by a series of small faults and has the potential to generate earthquakes with a magnitude of up to 6.0. Previous Occurrences

66 2023 LOCAL HAZARD MITIGATION PLAN
The following declared earthquake disasters are on record for San Bernardino County: FEMA Declaration String State Fiscal Year Declared Incident Type Incident Subcategory County DR-947-CA CA 1992 Earthquake Earthquake & Aftershocks San Bernardino (County) EM-3415-CA CA 2019 Earthquake Earthquakes San Bernardino (County) Rialto is situated near several active faults, including the San Andreas Fault, the San Jacinto Fault, and the Cucamonga Fault. In 2019, a swarm of small earthquakes occurred near the city, with the largest measuring at a magnitude of 3.5. The most significant earthquake to impact Rialto occurred in 1857, when a magnitude 7.9 earthquake struck the southern California region, rupturing the San Andreas Fault. While there were no buildings in the area at the time, the earthquake caused significant damage to infrastructure and altered the landscape of the region. In 1971, the San Fernando earthquake, which measured 6.6 on the Richter scale, caused damage to several buildings in Rialto and nearby cities. The earthquake resulted in 64 deaths and caused over $500 million in damages. Probability of Future Events and Impacts of Climate Change Likelihood of occurrence in the next ten years: High. On average, it is expected that a quake measuring 6.0 or greater in magnitude will occur in Southern California every few years. It is not possible to predict when a major earthquake will occur, but the USGS has estimated that there is a 75% chance that one or more earthquakes with a magnitude of 7.5 or greater will occur within the next thirty years. Some research indicates that climate change could result in “isostatic rebounds,” or a sudden upward movement of the crust because of reduced downward weight caused by glaciers, which could result in increased seismic and volcanic activity in previously glaciated areas. However, this will not impact Rialto directly.

67 2023 LOCAL HAZARD MITIGATION PLAN

3.5.9 – Epidemic / Pandemic Hazard Description An infectious disease is a disease caused by pathogenic microorganisms, characterized by clinical symptoms. Infectious diseases pose a major threat worldwide and cause millions of deaths annually. Transmission of infectious diseases can occur through various modes such as direct physical contact with infected individuals, exposure to contaminated food or water, exposure to bodily fluids, contact with contaminated objects, airborne inhalation, or vector-borne dissemination. An infectious disease can be classified based on its impact as endemic, epidemic, or pandemic. Endemic diseases are consistently present but at low levels (e.g., chicken pox in the United States). Epidemic diseases are sudden severe outbreaks (e.g., the bubonic plague during Medieval times). A pandemic disease is an epidemic that spreads widely across a region, continent, or the world (e.g., the 1957 flu pandemic caused millions of deaths globally). With global travel and trade, fears of pandemics have increased in recent years due to the potential for rapid spread. A pandemic is defined by the CDC as a worldwide epidemic that affects many people and crosses international borders, creating a public health emergency that impacts all sectors of society. It occurs when a virus undergoes significant antigenic drift or shift, resulting in a new and efficient strain that spreads from person-to-person without pre-existing immunity. The severity of the outbreak is generally unpredictable. A high number of infectious disease cases can strain healthcare infrastructure. The impact on morbidity and mortality may differ depending on the disease; it can disproportionately affect either younger and healthier people, as seen in the 1918 influenza pandemic, or older and medically-at-risk people, as happened with the recent COVID-19 outbreak. This can lead to worker shortages due to illness, isolation/quarantine, or caring for sick family members. It may also disrupt daily life and lead to shortages of goods and services. Strategies like "stay-at-home" orders and closing non-essential businesses can limit disease transmission but may also create additional burdens on productivity and essential services. Location and Extent A pandemic of a human infectious disease has the potential to impact the entire country, including California. Due to the integration of business and social activities both nationally and internationally, it is unreasonable to assume that any location would be exempt from

68 2023 LOCAL HAZARD MITIGATION PLAN
the threat of a pandemic. Locations with high population concentration, such as schools, retail areas, and special event venues, are at the greatest risk. Recent data on the COVID-19 outbreak indicates that individuals living in densely populated urban areas were more prone to contracting the virus, potentially due to close contact with other residents or visitors from other places. The ease of global transportation makes it increasingly challenging to contain local outbreaks, as infected or exposed individuals travel for business and leisure, possibly disseminating the disease worldwide within hours. Previous Occurrences FEMA Declaration String State Fiscal Year Declared Incident Type Incident Subcategory County EM-3428-CA CA 2020 Biological Covid-19 San Bernardino (County) DR-4482-CA CA 2020 Biological Covid-19 Pandemic San Bernardino (County) • Typhoid (19th and early 20th centuries): Before the advent of modern sanitation and water treatment systems, California, like many other places, faced occasional outbreaks of typhoid fever. • Spanish Flu (1918 Influenza Pandemic): The Spanish flu was a devastating influenza pandemic that swept across the globe between 1918 and 2020. • HIV/AIDS Epidemic (1980s - Present): The HIV/AIDS epidemic has had a profound impact on California, particularly in cities like San Francisco and Los Angeles. • H1N1 Influenza (2009 Pandemic): In 2009, a novel strain of influenza A (H1N1) emerged and caused a global pandemic. • Hepatitis A Outbreak (2017-2018): California experienced a hepatitis A outbreak primarily affecting unhoused populations in 2017-2018. • COVID-19 Pandemic (2020 - Present): The COVID-19 pandemic, caused by the novel coronavirus SARS-CoV-2, has had a significant impact on California. • Tuberculosis Epidemics (Various Periods): Tuberculosis (TB) has been a recurring public health concern in California, particularly in densely populated urban areas. • West Nile Virus Outbreaks (Various Periods): West Nile virus, transmitted by mosquitoes, has caused outbreaks in California over the years.

69 2023 LOCAL HAZARD MITIGATION PLAN
• Measles Outbreaks (Multiple Occurrences): Measles, a highly contagious viral disease, has had sporadic outbreaks in California over the years. These outbreaks have been attributed to low vaccination rates in some communities, Probability of Future Occurrences and Impacts of Climate Change Overall probability over next ten years: Low. Pandemics are relatively rare when compared to the frequency of natural disasters. When they do occur, however, they can have far-reaching effects. Even suppressed outbreaks of disease can have significant impacts to the localities they affect. It is difficult to accurately predict the likelihood of future pandemics. However, human encroachment into formerly natural areas worldwide increase the risk of hitherto unknown animal diseases making the jump into human populations. Public health systems should be aware of the potential for new diseases that may pose a threat to the populations they serve, and they should expect future pandemics to appear, some potentially more deadly than COVID-19. Climate change may impact the emergence and transmission of viruses by extending the habitat range of animals that carry them. Already, viruses such as West Nile or Zika have appeared in areas previously not hosting these viruses. It is likely that future diseases from warmer climates will spread along with those climates. 3.5.10 – Flood Hazard Description Floods are among the most common and widespread of all natural disasters. Nearly all communities in the United States at some point have experienced flooding, after spring rains, heavy thunderstorms, or winter snow thaws. Floods are typically caused by excessive precipitation and can be influenced by various factors such as topography, weather patterns, soil moisture, vegetation, and impervious surfaces. Drainages and streams can overflow if their capacity is surpassed by rainwater. In urban areas, the presence of pavement and other impermeable surfaces reduces the ground's ability to absorb excess water, necessitating the use of storm channels or

70 2023 LOCAL HAZARD MITIGATION PLAN
waterways. Floods can cause secondary hazards such as erosion or scouring of stream banks, roadway embankments, foundations, footings for bridge piers, and other features. High-velocity flow and debris carried by floodwaters can also cause impact damage to structures, roads, bridges, culverts, and other features, with debris accumulating on bridge piers and in culverts. In addition, floods can lead to the release of sewage and hazardous or toxic materials when wastewater treatment plants are inundated, storage tanks are damaged, and pipelines are severed. The standard for flooding is the so-called "100-year flood," a benchmark used by the Federal Emergency Management Agency to establish a standard of flood control in communities throughout the country. Thus, the 100-year flood is also referred to as the "regulatory" or "base" flood. It is important to note that it does not mean that only one flood of that size will occur every 100 years. What it means is that there is a one percent chance of a flood of that intensity and elevation happening in any given year. In other words, it is the flood elevation that has a one percent chance of being equaled or exceeded each year. And it could occur more than once in a relatively short period of time. (By comparison, the 10-year flood means that there is a ten percent chance for a flood of its intensity and elevation to happen in any given year.) Flash floods typically occur during the rainy seasons of fall and winter. The region’s dry soil makes matters worse since water has little chance to absorb the rainfall only adding to the problem. Flash floods occur suddenly, usually within 6 hours of the rain event, and result from heavy localized rainfall or levee failures. Flash floods can begin before the rain stops. Water level on small streams may rise quickly in heavy rainstorms, especially near the headwaters of river basins. Heavy rains can also cause flash flooding in areas where the floodplain has been urbanized. Many people are killed by flash floods when driving or walking on roads and bridges that are covered by water. In fact, flash floods are the number one weather-related killer in the United States. Even six inches of fast-moving flood water can knock a person off their feet, and a depth of only two feet of water will float many of today's automobiles. Location and Extent The San Bernardino County Flood Control District has identified several areas in Rialto that are at high risk of flooding, including parts of Lytle Creek and the San Sevaine Channel.

71 2023 LOCAL HAZARD MITIGATION PLAN
These areas are also prone to flash flooding due to the steep terrain in the nearby mountains, which can cause rainwater to quickly rush down to lower elevations. The Rialto Channel is a 6.79-mile storm drain channel that bisects the City from north to south. The channel commences at the outfall of a series of five large storm water catch basins that are located between the 210 Freeway and Etiwanda Road and under the jurisdiction of the San Bernardino County Flood Control District. It proceeds south along the west side of Cactus Avenue. The Channel proceeds southerly along the alignment of Cactus Avenue to a point south of west Rialto Avenue, where it makes a 45-degree turn to the southeast before it continues south approximately mid-block between Cactus Avenue and Lilac. South of Bloomington Avenue, the Channel makes a 45-degree turn and continues in a southeasterly direction, where it crosses under Valley Boulevard and under the Interstate 10 Freeway and Riverside Avenue south of the I-10. It continues in an alternating concrete-lined and natural channel until it empties into the Santa Ana River south of its crossing at Agua Mansa Road. The channel is a San Bernardino County Flood control facility and passes through Colton south of the I-10 and south of Agua Mansa Road. The Rialto Channel is dry for most of the year except during heavy rain events above the Rialto Water Treatment Plan. The Channel carries treated effluent released from the Treatment Plant year-round. This release is permitted and monitored and does not pose any flooding threat. During major storm events, there is a possibility of the channel overtopping at several locations located generally north of the channel’s intersection with Willow Street, between Valley Boulevard and San Bernardino Road. The existing earthen channel is known to be undersized for the maximum potential release from the Cactus Basin system. As of 2019, work was under way to improve and expand the Cactus Basin system to contain a 500-year even and the outlet is controlled to release no more flow than the downstream unimproved channel can contain. There are twelve locations where the channel crosses a major roadway by either a box culvert or bridge. These locations from south to north include: • Willow Avenue between Valley Boulevard and San Bernardino Road. • San Bernardino Road and Lilac • Bloomington Avenue • Randall Avenue • Merrill Avenue • Metrolink Railroad Right of Way • Cactus Avenue between Metrolink Right of Way and Rialto Avenue • Rialto Avenue west of Cactus Avenue.

72 2023 LOCAL HAZARD MITIGATION PLAN
• 2nd Street West of Cactus Avenue. • Foothill Boulevard west of Cactus Avenue. • Rosewood Ave west of Cactus Ave • Etiwanda Avenue west of Cactus Avenue. Floodplains and frequently flooded areas are typically identified by FEMA as Special Flood Hazard Areas (SFHAs), although flooding can occur outside of these areas. Low-lying regions near bodies of water are most susceptible to future flooding. FEMA maps and identifies floodplains on Flood Insurance Rate Maps (FIRMs) and assesses flood events based on their probability of occurrence. To illustrate, a flood that has a 1 in 100 (1.0 percent) chance of occurring in any given year is called a 100-year flood. Similarly, a flood that has a 1 in 500 (0.2 percent) chance of occurring in any given year is referred to as a 500-year flood. The 100-year flood serves as a reference point for significant flood events and is known as the "base flood." The three most prevalent categories described on FIRMs are: • Special Flood Hazard Area: The area within a 100-year floodplain. • Moderate Flood Hazard Area: The area outside of the 100-year floodplain but within the 500-year floodplain. • Minimum Flood Hazard Area: The area outside of the 500-year floodplain.

73 2023 LOCAL HAZARD MITIGATION PLAN
City of Rialto Flood Hazard Map (Source: https://scag.ca.gov/sites/main/files/file-attachments/rialto.pdf?1604951488 (2019))

74 2023 LOCAL HAZARD MITIGATION PLAN
Previous Occurrences FEMA Declaration String State Fiscal Year Declared Incident Type Incident Subcategory County DR-547-CA CA 1978 Flood Coastal Storms, Mudslides & Flooding San Bernardino (County) DR-690-CA CA 1983 Flood Flash Flooding San Bernardino (County) DR-687-CA CA 1983 Flood Flooding San Bernardino (County) DR-521-CA CA 1976 Flood Flooding, Tropical Storm Kathleen San Bernardino (County) DR-211-CA CA 1966 Flood Heavy Rains & Flooding San Bernardino (County) DR-935-CA CA 1992 Flood Rain/Snow/Wind Storms, Flooding, Mudslides San Bernardino (County) DR-223-CA CA 1967 Flood Severe Storms & Flooding San Bernardino (County) DR-253-CA CA 1969 Flood Severe Storms & Flooding San Bernardino (County) DR-615-CA CA 1980 Flood Severe Storms, Mudslides & Flooding San Bernardino (County)

75 2023 LOCAL HAZARD MITIGATION PLAN
DR-979-CA CA 1993 Flood Severe Winter Storm, Mud & Land Slides, & Flooding San Bernardino (County) DR-1952-CA CA 2011 Flood Severe Winter Storms, Flooding, And Debris And Mud Flows San Bernardino (County)
EM-3591-CA CA 2023 Flood Severe Winter Storms, Flooding, And Mudslides San Bernardino (County) EM-3592-CA CA 2023 Flood Severe Winter Storms, Flooding, Landslides, And Mudslides San Bernardino (County)
Flooding is not a common occurrence to the City, due to the City’s construction along the western bench of Lytle Creek and Rialto rests on an alluvial fan with a 2.5% slope to the southeast and the Santa Ana River Channel. The most immediate source of potential flooding within the City is the Rialto Channel. One of the most significant flooding events in Rialto occurred in 1969, when heavy rains caused the Lytle Creek to overflow, flooding homes and businesses in the area. The flood caused an estimated $10 million in damages and led to the evacuation of over 1,500 residents. In 2010, Rialto and other parts of San Bernardino County experienced a series of storms that caused flooding and mudslides. The San Sevaine Channel overflowed, flooding nearby streets and homes. The floodwaters also damaged several bridges and forced road closures throughout the city. More recently, in February 2019, heavy rain caused flooding in parts of Rialto, including the intersection of Foothill Boulevard and Cedar Avenue. The flooding caused traffic delays and led to the closure of several streets in the area.

76 2023 LOCAL HAZARD MITIGATION PLAN
Probability of Future Events and Impact of Climate Change Likelihood of occurrence in the next ten years: Medium. The probability of future flooding events in and around Rialto is difficult to predict with certainty, but climate change is expected to increase the frequency and severity of extreme weather events, including heavy rainfall and flooding. According to the Fourth National Climate Assessment, Southern California is expected to experience more frequent and intense precipitation events, which can increase the risk of flash flooding and mudslides. In addition, as temperatures continue to rise due to climate change, the snowpack in the nearby mountains is expected to decrease, leading to a shift from snowmelt to rainwater runoff, which can further increase the risk of flooding. 3.5.11 – Severe Rainfall Hazard Description When heavy rain occurs, it can fall at a rate so high that the water is unable to drain away quickly enough. This can result in flooding, causing inundation and potential damage to buildings, road networks, public areas, utilities, critical infrastructure, and other assets. In California, heavy rainfall events are typically brief and intense bursts of rain, although in some instances, heavy rain can persist for several days. Precipitation levels in California fluctuate from year to year, largely dependent on the amount of moisture the state receives from atmospheric rivers. These rivers are pathways along which moist air travels from the tropics to the continents, and when this moisture reaches California, it can fall as either rain or snow. One of the most well-known atmospheric rivers in California is the "Pineapple Express," which brings wet air from the ocean surrounding Hawaii to California. In some years, a substantial amount of moisture can be transported by atmospheric rivers, resulting in heavy rainfall events in California. The weather pattern known as El Niño, or the Southern Oscillation, is another factor that can influence rainfall in southern California, especially during winter. El Niño occurs when the surface of the eastern tropical Pacific Ocean warms, causing warm, moist air to evaporate into the atmosphere. This moisture is then carried by winds to the eastern Pacific and the American continents, where it can result in increased rainfall. While El Niño doesn't always

77 2023 LOCAL HAZARD MITIGATION PLAN
lead to increased rainfall, it generally increases the likelihood of a winter with above-average precipitation. Location and Extent Severe rainfall may potentially impact the entirety of the planning area for the city of Rialto. One of the main factors that contribute to flooding in Rialto and the surrounding areas is the region's geography. The city is located near the foothills of the San Bernardino Mountains, which can create conditions for flash floods and mudslides. Additionally, the soil in the region is often hard and compacted, which means that it is less able to absorb large amounts of water quickly. This can lead to water pooling on the surface, which can cause flooding. Flooding can have significant impacts on the community, including property damage, road closures, and power outages. In some cases, flooding can also pose a threat to public safety, particularly if floodwaters are fast-moving or carry debris. The region is particularly vulnerable to flooding during periods of heavy rainfall, particularly in areas that are located near the foothills or other areas with limited drainage.

Measuring Heavy Rain Events

78 2023 LOCAL HAZARD MITIGATION PLAN
Rain Type Description Heavy rain More than 4 mm per hour but less than 8 mm per hour Very heavy rain Greater than 8 mm per hour Moderate shower Greater than 2 mm, but less than 10 mm per hour Heavy shower Greater than 10 mm per hour, but less than 50 mm per hour Violent shower Greater than 50 mm per hour Source: https://water.usgs.gov/edu/activity-howmuchrain-metric.html Previous Occurrences FEMA Declaration String State Fiscal Year Declared Incident Type Incident Subcategory County DR-677-CA CA 1983 Coastal Storm Coastal Storms, Floods, Slides & Tornadoes San Bernardino (County) EM-3248-CA CA 2005 Hurricane Hurricane Katrina Evacuation San Bernardino (County) DR-1577-CA CA 2005 Severe Storm Severe Storms, Flooding, Debris Flows, And Mudslides San Bernardino (County) DR-1585-CA CA 2005 Severe Storm Severe Storms, Flooding, Landslides, And Mud And Debris Flows San Bernardino (County)
DR-1203-CA CA 1998 Severe Storm Severe Winter Storms And Flooding San Bernardino (County)

79 2023 LOCAL HAZARD MITIGATION PLAN
DR-1046-CA CA 1995 Severe Storm Severe Winter Storms, Flooding Landslides, Mud Flow San Bernardino (County)
DR-1884-CA CA 2010 Severe Storm Severe Winter Storms, Flooding, And Debris And Mud Flows San Bernardino (County)
DR-1044-CA CA 1995 Severe Storm Severe Winter Storms, Flooding, Landslides, Mud Flows San Bernardino (County)
• 1862 Great Flood: Although not specific to Rialto alone, this event was one of the most significant in Southern California's history. The heavy rains during this winter caused widespread flooding throughout the region, including Rialto. The entire area became a vast inland sea, causing substantial damage to infrastructure and agriculture. • February 1980: Rialto experienced a severe rainstorm in February 1980. The city received heavy rainfall, leading to flooding in various parts of the community. The storm caused damage to roads, bridges, and properties. • February 1993: Rialto and the surrounding areas were hit by a powerful winter storm in February 1993. The city received significant rainfall, leading to widespread flooding and property damage. The storm caused road closures, power outages, and prompted evacuations in some areas. • February 2010: Another significant rainfall event occurred in February 2010, causing flooding in Rialto and other parts of Southern California. The heavy rains led to street flooding, property damage, and the closure of numerous roads. Probability of Future Events and Impacts of Climate Change Overall probability over next ten years: High. The following chart from NOAA’s Climate Explorer describes trends in the number of days with rainfall greater than 3 inches to 2100.

80 2023 LOCAL HAZARD MITIGATION PLAN

Rialto can expect to experience more frequent and intense heavy rainstorms due to the expected increase in the frequency and overall amount of rainfall in California. By the end of the 21st century, it is projected that intense rainfall events may occur twice as often and may result in up to a 40% increase in total rainfall. According to California’s Fourth Climate Assessment for the Los Angeles Region: Atmospheric rivers are regions of high water vapor transport from the tropics to the Pacific Coast of the U.S. that can produce intense topographic-induced precipitation along southern California mountain ranges (Neiman et al. 2008; J. Kim et al. 2012; Harris and Carvalho 2017; Guan et al. 2013; Payne and Magnusdottir 2014). Such events have helped pull the region out of droughts, although they are also responsible for devastating floods and mudslides (Ralph et al. 2006; Guan et al. 2013; M. D. Dettinger 2013). Between 1979-2013, 72 atmospheric rivers were identified as landfalling along the coast of southern California, approximately 2-3 events each year, though significant interannual variability exists. The frequency of atmospheric rivers over southern California has a potential connection to some natural climate variability patterns (Neiman et al. 2008; J. Kim et al. 2012; Harris and Carvalho 2017; Guan et al. 2013; Payne and Magnusdottir 2014). Analysis of several previous-generation GCMs by (Dettinger 2011a) suggest that the frequency of atmospheric river events may increase in the future, and that the storms themselves will be associated with higher water vapor transport rates compared to historical conditions. Moreover, the peak season of atmospheric rivers may also lengthen, which could extend the food-hazard season in California. The current generation of GCMs project a nearly 40% increase in precipitation during atmospheric river events over southern California by the late-21st century under RCP8.5. The number of atmospheric

81 2023 LOCAL HAZARD MITIGATION PLAN
river events is also projected to increase in the future, possibly around a doubling of days by the end of the century (Warner et al. 2015; Hagos et al. 2016; Gao et al. 2015). Understanding future characteristics of atmospheric rivers, particularly over local spatial scales in California, remains an active area of research. As described above in “Flooding”, similar factors will come into play affecting the intensity and frequency of heavy rain. Increased periods of little to no rainfall and associated drying out of soils could also contribute to reduced absorptive capacity and increased surface transport of water from heavy rainfall, intensifying localized flooding. 3.5.12 – Severe Wind Hazard Description The City of Rialto has experienced most of its high wind incidents due to Santa Ana wind conditions. Santa Ana winds are warm and dry winds that typically blow offshore from the east or northeast and occur below the passes and canyons of the coastal ranges of Southern California and in the Los Angeles basin. The Santa Ana winds frequently blow at remarkable speeds in the Santa Ana Canyon, which gives them their name. The National Weather Service offices in Oxnard and San Diego typically set speed thresholds for these winds, reserving the term "Santa Ana" for winds that exceed 25 knots. As these winds move through canyons and passes, they can accelerate to speeds of up to 35 knots and produce gusts of 50 or even 60 knots.

82 2023 LOCAL HAZARD MITIGATION PLAN
Location and Extent The entirety of the planning area for city of Rialto may be impacted by high wind events. In Southern California, the Santa Ana winds are the most common type of severe wind event. These winds are caused by high pressure over Nevada and Utah, which pushes air down from the high desert towards the ocean, particularly during fall and winter. The measurement of winds typically employs the Beaufort scale, which was created in 1805 and sorts wind occurrences based on their speed and effects on a force scale ranging from 0 to 12. Wind events classified as force 9 or higher are typically recognized as severe wind events.

83 2023 LOCAL HAZARD MITIGATION PLAN
Previous Occurrences FEMA Declaration String State Fiscal Year Declared Incident Type Incident Subcategory County DR-677-CA CA 1983 Coastal Storm Coastal Storms, Floods, Slides & Tornadoes San Bernardino (County) EM-3248-CA CA 2005 Hurricane Hurricane Katrina Evacuation San Bernardino (County) DR-1577-CA CA 2005 Severe Storm Severe Storms, Flooding, Debris Flows, And Mudslides San Bernardino (County) DR-1585-CA CA 2005 Severe Storm Severe Storms, Flooding, Landslides, And Mud And Debris Flows San Bernardino (County)
DR-1203-CA CA 1998 Severe Storm Severe Winter Storms And Flooding San Bernardino (County) DR-1046-CA CA 1995 Severe Storm Severe Winter Storms, Flooding Landslides, Mud Flow San Bernardino (County)
DR-1884-CA CA 2010 Severe Storm Severe Winter Storms, Flooding, And Debris And Mud Flows San Bernardino (County)

84 2023 LOCAL HAZARD MITIGATION PLAN
DR-1044-CA CA 1995 Severe Storm Severe Winter Storms, Flooding, Landslides, Mud Flows San Bernardino (County)
Santa Ana wind events are relatively common in Rialto and surrounding areas. In recent times, one notable example of a high wind event that impacted Rialto and neighboring cities occurred in December 2011. This event brought strong winds to the area, with gusts of up to 100 mph reported in some locations. The winds knocked down trees and power lines, leading to widespread power outages and disruptions to transportation. In Rialto specifically, the wind event caused several traffic accidents and led to power outages affecting thousands of residents. In addition, other high wind events have impacted the region. For example, in January 2019, a wind event with gusts of up to 60 mph was reported in the nearby city of San Bernardino, leading to power outages and tree damage. In September 2020, a similar wind event caused widespread power outages and damaged homes and vehicles in nearby cities such as Fontana and Rancho Cucamonga. Probability of Future Events and Impacts of Climate Change Overall probability over next ten years: High. The probability of high wind events in Rialto and the surrounding areas depends on several factors, including atmospheric conditions, the location and topography of the region, and the season. Generally speaking, the probability of high wind events is highest during the fall and winter months, when the Santa Ana winds are most likely to occur. However, these events can occur at any time of year and can vary in intensity and duration. It is difficult to predict exactly how climate change will impact high wind events in the Rialto area and surrounding region. However, some research suggests that climate change may increase the frequency and intensity of Santa Ana winds in Southern California. This is because climate change is expected to cause warming in the western United States, which could lead to greater temperature contrasts between the coast and the inland areas and increase the pressure gradients that drive Santa Ana winds. Additionally, climate change could impact precipitation patterns, which may further exacerbate the risk of wildfire and other impacts associated with high wind events.

85 2023 LOCAL HAZARD MITIGATION PLAN

86 2023 LOCAL HAZARD MITIGATION PLAN
Section 4 – Vulnerability Assessment Element B: Risk Assessment Requirements B2. Does the plan include a summary of the jurisdiction's vulnerability and the impacts on the community from the identified hazards? Does this summary also address NFIP insured structures that have been repetitively damaged by floods? (Requirement 44 CFR § 201.6(c)(2)(ii)) 4.1 Lifelines and Critical Infrastructure FEMA-Defined Community Lifelines FEMA's Lifelines are a framework for identifying and prioritizing critical infrastructure and services that are essential to the functioning of communities during and after a disaster. The Lifelines framework was developed by the Federal Emergency Management Agency (FEMA) to help emergency managers and first responders prioritize their response efforts and allocate resources during a disaster. The concept of Lifelines emerged from the realization that disasters can have wide-ranging impacts on a community's infrastructure and services, and that disruptions to these critical systems can significantly hinder response and recovery efforts. The Lifelines framework was developed to identify these critical systems and services and prioritize them based on their importance to overall community functioning and resilience. There are seven FEMA Lifelines, each of which represents a critical area of infrastructure or service. Critical facilities are categorized under the following lifelines: • Safety and Security: This includes law enforcement/security, search and rescue, fire services, government service, and responder safety.

87 2023 LOCAL HAZARD MITIGATION PLAN
• Food, Water, and Shelter: This encompasses evacuations, schools, food/potable water, shelter, durable goods, water infrastructure, and agriculture. • Health and Medical: This lifeline involves medical care (hospitals), patient movement, public health, fatality management, health care, and supply chain. • Energy: Power (grid), temporary power, and fuel. • Communications: This includes infrastructure, alerts, warnings, messages, 911 and dispatch, responder communications, and financial services. • Transportation: This encompasses highway/roadway, mass transit, railway, aviation, and pipeline. • Hazardous Materials: This includes facilities, hazardous debris, pollutants, and contaminants. The Lifelines framework is designed to help emergency managers and first responders prioritize their response efforts and allocate resources based on the criticality of each Lifeline. By prioritizing the most critical Lifelines, emergency responders can work to restore essential services and infrastructure more quickly, which can help to speed up the overall recovery process and reduce the impact of the disaster on the community. 4.2 Critical Facility List Critical Infrastructure A critical infrastructure list was developed with input from City staff and coordinated with both THIRA preparation and development of the revised Safety Element of the City’s General Plan. During the April 3, 2023 hazards and vulnerability assessment workshop, City staff verified hazard scoring for critical facilities based on the following scale by hazard: • 0 – No Impact • 1 – Minor Impact • 2 – Moderate Impact • 3 – Major Impact • 4 – Extreme Impact Scores were added together to produce a cumulative Vulnerability Score for identified facilities.

88 88
2023 LOCAL HAZARD MITIGATION PLAN Critical Facility List Name Lifeline Address Vulnerability Score Rialto Police Annex Safety and Security 429 W. Rialto Ave, Rialto CA 92376 12 Rialto Public Works Water & Sewer Food, Water & Shelter 325 W Rialto, Rialto, CA 92376 11 San Gabriel Valley Water Co Reservoir Food, Water & Shelter 1482 W Summit Ave, Rialto, CA 92377 11 Cactus Reservoir Food, Water & Shelter 725 W Baseline Rd, Rialto, CA 92376 10 Carter Branch Library Food, Water & Shelter 2630 N Linden Ave, Rialto, CA 92377 10 Cedar Reservoir Food, Water & Shelter 2610 N Cedar, Rialto, CA 92377 10 Rialto Fitness and Aquatic Center Food, Water & Shelter 1243 S Riverside Ave, Rialto, CA 91711 10 Water Treatment Plant Food, Water & Shelter 501 E Santa Ana, Rialto, CA 92376 10 Rialto Network Communications 150 S Palm, Rialto, CA 92376 9 Rialto Senior Center Food, Water & Shelter 1411 S Riverside, Rialto, CA 92376 9 Fire Station 201 Safety and Security 131 S. Willow, Rialto, CA 91711 9 Fire Station 202 Safety and Security 1700 N Riverside, Rialto, CA 92376 9 Fire Station 203 Safety and Security 1550 N Ayala, Rialto, CA 92376 9 Fire Station 204 Safety and Security 3288 N Alder, Rialto, CA 92377 9 Rialto City Clerk's Office Safety and Security 290 W. Rialto Ave. Rialto CA 92376 9 Fire Station 205 Safety and Security 1485 S. Willow Ave. Rialto CA 92376 8 Public Works Building and City Yard government facilities Safety and Security 335 West Rialto Avenue, Rialto, CA 92376 8 Rialto City Hall Safety and Security 150 S Palm, Rialto, CA 92376 8 Rialto IT Department Safety and Security 251 S. Willow Ave. Rialto CA 92376 8 Rialto Police Headquarters Safety and Security 128 N. Willow, Rialto, CA 92376 8 City Garage Safety and Security 245 & 247 S. Willow, Rialto, CA 92376. 7 Rialto Procurement Department Safety and Security 249 S. Willow Ave. Rialto CA 92376 7 Easton Reservoir Food, Water & Shelter 140 W Easton, Rialto, CA 92376 6

89 2023 LOCAL HAZARD MITIGATION PLAN Name Lifeline Address Vulnerability Score Highland Reservoir Food, Water & Shelter 100 E Easton, Rialto, CA 98376 6 San Gabriel Valley Water Co Reservoir (1) Food, Water & Shelter 1133-381-28-0000 6 San Gabriel Valley Water Co Reservoir (2) Food, Water & Shelter 0240-191-15-0000 6 Sanhill WTP Water Treatment Food, Water & Shelter 437 N Riverside Ave, Rialto, CA 92376 6 Veolia Water West Operating Sewage Treatment Food, Water & Shelter 325 W Rialto Ave, Rialto, CA 92376 6 Veolia Water West Operating Water Treatment Food, Water & Shelter 855 W Baseline Rd, Rialto, CA 92376 6 Wastewater Treatment Facility Water & Sewer (Veolia Water West) Food, Water & Shelter 501 E Santa Ana, Bloomington, CA 92316 6 Community Center Food, Water & Shelter 214 N Palm, Rialto, CA 92376 4 Rialto Branch Library Food, Water & Shelter 251 W 1st St, Rialto, CA 92376 4 West SB County Water District Reservoir (1) Food, Water & Shelter 3622 N Riverside Ave, Rialto, CA 92377 4 West SB County Water District Reservoir (2) Food, Water & Shelter 0239-182-51-0000 4 West SB County Water District Reservoir (3) Food, Water & Shelter 0239-112-26-0000 4 West Valley Water District Main Office Food, Water & Shelter 855 W Baseline Rd, Rialto, CA 92376, 3

90 90
2023 LOCAL HAZARD MITIGATION PLAN

4.3 Individual Hazard Vulnerability Analysis This section serves to identify each hazard confronting the community and its vulnerabilities to that hazard. 4.3.1. Extreme Heat 4.3.1.1 Overall Vulnerability and Impact Extreme heat includes heatwaves and sustained heat events. 4.3.1.2 Population The entire population of the City of Rialto can be negatively impacted by extreme heat. Seniors, infants, and other especially vulnerable populations would be affected more dramatically. Increased use of air conditioning can put pressure on the power grid, increasing the possibility of power loss, which would severely impact humans and animals. Unhoused people are especially vulnerable as well. Extreme heat can have serious consequences for human health, including headaches, dizziness, weakness, cramping, nausea, vomiting, confusion, dehydration, and even death. Vulnerable populations such as the very young, elderly, the unhoused and those with special needs or disabilities are particularly at risk, especially during prolonged heat waves. In addition to the groups identified above, the following demographic groups are also more susceptible to the effects of extreme heat: • Women who are pregnant • Persons with medical conditions (e.g., heart disease, diabetes, high blood pressure, insulin-dependent, dialysis) • Persons with mental illness/disabilities or cognitive disorders • Persons who use medical equipment (e.g., ventilators, oxygen, G-tubes) • Individuals with drug or alcohol dependencies • Persons with mobility devices (e.g., wheelchairs, walkers, canes) • Persons who are non-ambulatory • Persons who are socially isolated • Persons who do not speak English with minimal access to current weather information in their own language. 4.3.1.3 Critical Facilities

91 2023 LOCAL HAZARD MITIGATION PLAN
Extreme heat can affect critical infrastructure such as roads, bridges, power lines, and water supply systems. Heat stress on metal and road materials, as well as increased use, can cause system breakdowns and outages as well as outright damage, as seen during the “heat dome” event in the Pacific Northwest in 2021. Additionally, the high demand for energy due to the increased use of air conditioning during heat events can cause utility “brownouts” and “blackouts.” Intentional or unintentional drops in voltage in an electrical power supply system or grid are referred to as brownouts. Brownouts are used by power companies in emergencies to prevent total power outages and can last for minutes or hours. Different types of electrical equipment react differently to brownouts. On the other hand, a short- or long-term loss of electrical power to a limited or widespread area is known as a blackout. Overloading the system, as can occur during an extreme heat event, can lead to blackouts. Particularly vulnerable critical facilities include the Southern California Edison transmission lines on the south and north ends of the city, as well as the Kinder Morgan Colton Terminal fuel distribution pipeline system and the Union Pacific Rail Yard, one of the largest in the United Sates. Power outages by themselves are a significant enough hazard to Rialto to be mentioned separately later in this section. 4.3.1.4 Non-Critical Facilities Sustained extreme heat can have impacts on physical infrastructure such as overhead and transmission wires. By encouraging residences and businesses to use air conditioning, it can also put pressure on the power grid, increasing the possibility of power loss. Non-critical facilities include homes of older construction in the downtown area. Rialto’s 12 mobile home parks could also be heavily impacted as many of them are homes for vulnerable populations and are spread out throughout the city. Other non-critical facilities are the large warehouses in the industrial park north of Baseline Road south of Renaissance Parkway between North Linden Ave and Alder Ave and south of I-10 along Riverside Ave. 4.3.1.5 Environment Prolonged extreme heat can cause severe damage to the natural environment, particularly the water supply, which can affect drinking water as well as other uses. The combination of extreme heat and drought can result in significant crop loss and increase the risk of wildfire. This will affect plant growth and survival from personal gardens to shade trees and recreational landscapes. 4.3.1.6 Future Trends in Development

92 2023 LOCAL HAZARD MITIGATION PLAN
Extreme heat events are projected to increase for the foreseeable future. Future developments will add to the number of people exposed to these events. 4.3.2 Power Outages 4.3.2.1 Overall Vulnerability and Impact The most immediate impact of a power outage is typically felt in homes and businesses. When the power goes out, residents and employees may experience a loss of lighting, heating, or cooling, and access to electronic devices. This can result in inconvenience, discomfort, and potential safety hazards, especially if the outage occurs at night or during extreme weather conditions. 4.3.2.2 Population The entire City could be vulnerable to a widespread power outages. Smaller portions of the City may be vulnerable to smaller outages. One of the most significant hazards of power outages during extreme heat is the risk of heat-related illnesses. When power goes out, air conditioning units and fans stop working, which can lead to indoor temperatures rising quickly. This can lead to dehydration, heat exhaustion, and even heatstroke, especially among vulnerable populations such as the elderly, young children, and those with preexisting medical conditions. Historically, sustained extreme heat events have resulted in significant deaths among vulnerable populations without air conditioning or working fans, such as the 1995 Chicago heat wave. 4.3.2.3 Critical Facilities. All government facilities can be affected by rolling blackouts and power failures. It is predicted that the State of California will experience more rolling blackouts in the future. In addition to homes and businesses, power outages can also impact essential services such as hospitals, emergency response systems, and water treatment facilities. Hospitals and medical facilities rely on electricity to power life-support systems and medical equipment, and a loss of power can lead to delays or interruptions in medical care. Emergency response systems such as 911 call centers and police and fire departments also rely on electricity to function, and a power outage can hinder their ability to respond to emergencies quickly. Water treatment facilities are another critical service that can be impacted by power outages. These facilities rely on electricity to pump and treat water, and a loss of power can result in a disruption in the water supply or a decrease in water quality.

93 2023 LOCAL HAZARD MITIGATION PLAN

4.3.2.4 Non-Critical Facilities. All neighborhoods in Rialto are vulnerable to rolling blackouts and power outages. 4.3.2.5 Environment There are relatively few impacts on the natural environment due to power outages. 4.3.2.6 Future Trends in Development While rolling blackouts do not cause the devastation of other hazards, they can severely impact the City's ability to provide emergency and regular services to its constituents. In addition, if businesses are unable to operate due to a power loss, revenue is substantially affected. Energy emergencies can cause fatalities, injuries, displaced populations, and public health issues. 4.3.3 Drought 4.3.3.1 Overall Vulnerability and Impact Rising temperatures in California are expected to impact and reduce water supplies across the state. Much of California's water comes from snowmelt in the High Sierra, a part of the Sierra Nevada mountain range. As temperatures rise due to climate change, the precipitation that would have fallen as snow is expected to become rainfall, leading to less snowfall and therefore, less meltwater from the Sierra Nevada snowpack, reducing the water that would have flowed into Southern California's reservoirs and aqueducts. This could lead to a strain on the City's imported water supply. During droughts, water customers are instructed to use less water, which in turn leads to decreased revenue for local water utilities with no reduction in fixed costs. As a result, water utilities often raise rates to make up for lost revenue. The reduction in water flow also leads to decreased sewage flows, causing an increase in contaminants in the water supply. This can affect the availability of drinking water and water for agriculture, leading to a decrease in food supply, a loss of biodiversity, increased mortality in humans and animals, an increase in disease, and a rise in endangered species. 4.3.3.2 Population. The entire population of the City of Rialto is vulnerable to drought. Drought impacts the entire city through reductions in water supply and related impacts. A shortage of water can cause dehydration, which can lead to symptoms such as headaches, dizziness, weakness, cramping, nausea, vomiting,

94 2023 LOCAL HAZARD MITIGATION PLAN
confusion, and, in extreme cases, death. Drought can also coincide with high temperatures, exacerbating the effects and putting vulnerable populations, such as young children, the elderly, and those with disabilities, at greater risk. As the population grows in areas prone to hazards, or as the number of people with special needs increases, their vulnerability to drought also increases. 4.3.3.3 Critical Facilities. Drought does not have significant direct impacts on critical infrastructure with the exception of water utility lines and facilities and plants at recreational facilities. 4.3.3.4 Non-Critical Facilities. Drought does not have major structural impacts but can impact residential water availability. Increased prices may result in lower-income populations using less water, increasing the likelihood of dehydration or other negative health impacts. 4.3.3.5 Environment The effects of drought are widespread and reach beyond geographic boundaries. These impacts are predominantly seen in water scarcity and the loss of crops and livestock in agricultural regions, and in increased difficulties in providing sufficient water in urban areas. The economic consequences of drought can be complex, as it affects numerous industries and has a ripple effect throughout the economy. This is because water is a critical component in the production of goods and provision of services. If a drought persists for multiple years, the direct and indirect economic impacts can be substantial. Drought conditions result in decreased water availability for plant and animal habitat from sources such as lakes, streams, aquifers, soil, wetlands, springs, and other surface and subsurface sources. This reduction in water quality can alter the levels of salinity, bacteria, turbidity, pH, and temperature, potentially affecting the aquatic habitat of plants and animals, and the health of livestock if they ingest too much salt or bacteria. 4.3.3.6 Future Trends in Development The competing forces of potential increases in population and increased efficiency of water use may effectively cancel one another out. This would leave the City at greater vulnerability overall to drought conditions caused far outside of its boundaries. Alternative and currently speculative ideas for maximizing rainfall and moisture may help compensate for this trend in the global climate. 4.3.4 Wildfire

95 2023 LOCAL HAZARD MITIGATION PLAN

4.3.4.1 Overall Vulnerability and Impact Southern California's brush plants are largely composed of chaparral, which grows quickly and leaves behind dead vegetation that is nutrient-rich and released into the soil through burning. Some chaparral plants, like Ceanothus, have flammable resin coatings on their leaves, while others, such as Chamise (greasewood), produce volatile gases when burned and leave a water-resistant residue in the soil that can cause erosion on denuded slopes, increasing the risk of post-fire flash flooding and mudslides in nearby communities. 4.3.4.2 Population Northern neighborhoods in the City of Rialto may be vulnerable to direct impacts of wildfire. Sparks from fires near the mountains and in undeveloped areas may spread across roads to homes. Any people who are unable or unwilling to evacuate would be directly vulnerable. Smoke from wildfires in other areas can directly and adversely impact human health due to reductions in air quality. 4.3.4.3 Critical Facilities Fire growth is related to building density, types of building construction, the presence and amount of flammable materials, wind speed and direction, width of fire breaks, water supply, time of fire department arrival, and available fire fighter resources. Fire's primary effects, which include loss of life, injury, and destruction of buildings and wildlife, are well known. However, it also has several secondary effects, such as overburdened public utilities, reduced water supplies, disrupted communication systems due to downed power lines and road closures. Wildfires can cause damage to structures, utilities, transportation routes, and communication resulting in loss of revenue and ability to provide emergency, essential, and non-essential services. High-voltage transmission lines are partially located in areas in northern Rialto within very high fire hazard severity zones. 4.3.4.4 Non-Critical Facilities A significant portion of the north end of the city is located in the very high fire hazard severity zone with exposure to thousands of homes along Lytle Creek. This is also large protected open space area for habitat. 4.3.4.5 Environment

96 2023 LOCAL HAZARD MITIGATION PLAN
Bare hillsides from fires just north of the City boundaries increase the flow of water and material, putting a strain on flood control facilities and leading to traveling debris. 4.3.4.6 Future Trends in Development Several newer developments in the City are in its northern portion, adjacent to undeveloped areas and within the very high fire hazard severity zone. Any potential future annexations north of the City would put additional areas of severe vulnerability directly within City limits. 4.3.5 Hazardous Materials 4.3.5.1 Overall Vulnerability and Impact The City of Rialto has a moderate vulnerability from hazardous materials events. 4.3.5.2 Population. In the event of a hazardous materials event, varying areas of the City could be impacted, depending on proximity to the event itself. 4.3.5.3 Critical Facilities. Specific sites within the city include the Kinder Morgan Colton Terminal and the Union Pacific Rail Yard. Both are facilities south of the I-10 freeway at Riverside Ave with significant amounts of hazardous materials, transportation of hazardous materials and the potential is high for hazardous materials incidents in this area. We are also served by three freeway systems. Rialto is served by three freeway systems, I-10 on the south, I-210 in the core (center) and I-15 on the north end which are all hazardous materials transportation corridors. Freeways within the City limits could be directly impacted by a hazardous materials spill from vehicles, as well as rail lines from rail spills. 4.3.5.4. Non-Critical Facilities. Non-critical infrastructure in close proximity of a hazardous materials event would be impacted in the event of a hazardous materials-related incident. An incident could also result in traffic and congestion from evacuation routes and areas closed off due to hazardous material incidents along the freeway system. There also may be impacts to adjacent homes and businesses. 4.3.5.5 Environment

97 2023 LOCAL HAZARD MITIGATION PLAN
Impacts on plants or animals are likely to be similar to impacts on humans in the event of a hazards materials-related incident. 4.3.5.6 Future Trends in Development It is unlikely that future trends in development will have a significant impact on the City’s vulnerability to hazards materials incidents. 4.3.6 Cyberattack 4.3.6.1 Overall Vulnerability and Impact Cyberattacks can impact local government, services, and businesses in a variety of ways, depending on the type and severity of the attack. Local Government: • Emergency Services: Cyberattacks can disrupt emergency services such as 911 systems, which can prevent people from getting the help they need in a timely manner. • Public Utilities: Cyberattacks can target public utilities such as water and power systems, potentially causing widespread outages and other disruptions. • Transportation Networks: Cyberattacks can target transportation networks such as traffic signals and public transit systems, causing delays and safety hazards. • Public Records: Cyberattacks can compromise public records such as birth certificates, social security numbers, and other sensitive information. Services: • Financial Services: Cyberattacks can target financial institutions such as banks, potentially compromising sensitive financial data and disrupting financial transactions. • Healthcare: Cyberattacks can compromise healthcare systems, potentially putting patient data and even lives at risk. • Retail: Cyberattacks can compromise retail systems, potentially exposing customer data and leading to financial losses and reputational damage. • Education: Cyberattacks can target educational systems, potentially compromising sensitive data such as student records and grades. Businesses:

98 2023 LOCAL HAZARD MITIGATION PLAN
• Intellectual Property: Cyberattacks can target businesses' intellectual property such as trade secrets, patents, and other sensitive information. • Financial Information: Cyberattacks can compromise businesses' financial data, potentially leading to financial losses and reputational damage. • Supply Chain Disruptions: Cyberattacks can disrupt businesses' supply chains, causing delays and financial losses. • Reputational Damage: Cyberattacks can cause reputational damage to businesses, potentially leading to a loss of customers and revenue. Laptops generally have 4-5 hours of power capacity, so in the event of a power outage, they could quickly run down without available power sources. And without an operating network to log in to, their utility would be seriously compromised. This becomes an issue in the case of another pandemic or other situation requiring widespread remote work as during the beginning of the COVID-19 pandemic – ensuring operation of the network will be key to ensuring the continued functioning of the City. 4.3.6.2 Population The general population may be subject to cyberattack through attacks on other institutions or individual responses to phishing or other online scams. More vulnerable are businesses and city government as they are more frequently the targets of attacks. In addition, certain populations such as the elderly, disabled, and unhoused people may be more vulnerable to the impacts of cyberattacks on local government and services. For example, if emergency services or public utilities are disrupted, these populations may have a more difficult time accessing the resources they need to stay safe and healthy. 4.3.6.3 Critical Facilities Every facility today is to some degree supported by IT technology, from access systems to the power grid. Beyond specific critical facilities, other elements of infrastructure could be affected, from traffic lights to modern electric vehicles. Therefore, all critical facilities are vulnerable to this hazard. 4.3.6.4 Non-Critical Facilities Virtually all non-critical facilities are vulnerable to cyberattack, although to lesser degrees. 4.3.6.5 Environment Cyberattack has no direct impact on the environment. Shutdowns of certain systems may cause events that have impacts on the environment, however.

99 2023 LOCAL HAZARD MITIGATION PLAN

4.3.6.6 Future Trends in Development As networked systems and new forms of information technology such as artificial intelligence become more common, the City’s vulnerability to cyberattack will only grow. A cyberattack paired with other hazards such as extreme heat could cause power outages with the potential to kill vulnerable inhabitants of the City, including the elderly and the unhoused. 4.3.7 Terrorism/Armed Assailant 4.3.7.1 Overall Vulnerability and Impact Terrorism, whether from an organized group or from a lone active assailant, is a constant shadow over many aspects of life in the United States. These kind of events can be carried out not only with guns but with explosive devices or sabotage of infrastructure such as attacks on electrical transformers or attempts to poison water supplies. 4.3.7.2 Population Populations within Rialto most vulnerable to a terrorist event include concentrations of people at festivals, farmer’s markets, restaurants, churches or stores as well as students in Rialto schools. 4.3.7.3 Critical Facilities The most vulnerable critical facilities in Rialto include City Hall, the Police and Fire Departments, and City-owned recreational facilities. These are likely targets for someone attempting to cause a mass-casualty event. Critical infrastructure, such as power plants, water treatment facilities, and communication systems, are essential to the functioning of the City. An attack on these facilities could disrupt vital services and cause significant damage to the City’s infrastructure. 4.3.7.4 Non-Critical Facilities Businesses and public spaces, such as parks, shopping centers, and public transportation hubs, are potential targets for terrorist attacks. For example, an attack on a crowded public space could cause mass casualties and widespread panic. Religious institutions, such as churches and synagogues, are also potential targets for terrorist attacks. 4.3.7.5 Environment

100
2023 LOCAL HAZARD MITIGATION PLAN
The environment itself is not a major target of potential terrorist or active assailant incidents in the City of Rialto. 4.3.7.6 Future Trends in Development Future trends in development are not likely to impact the vulnerability of the City to these kinds of events. 4.3.8 Earthquake 4.3.8.1 Overall Vulnerability and Impact Earthquakes can cause significant damage to the built environment, including collapsed structures that may trap or bury individuals, resulting in loss of life and expensive cleanup efforts. Many buildings in California were constructed before 1993, when building codes were less stringent, and retrofitting is not mandatory except in certain circumstances, leading to a high number of vulnerable structures. After an earthquake, significant time is devoted to the removal of debris from various structures, including brick, glass, wood, steel, concrete building components, and office or home contents following damage. Seismic activity poses a significant threat to businesses, from large corporations to small retail shops. Even a single day of production downtime can result in tremendous economic loss, particularly for businesses with national or global markets. These losses can be a burden for owners who may struggle to recover. According to FEMA, forty percent of businesses fail to reopen after a disaster, and another twenty-five percent fail within one year. Similarly, statistics from the United States Small Business Administration show that over ninety percent of businesses fail within two years after being hit by a disaster. Fires are frequently triggered by downed power lines or broken gas mains during earthquakes. If fire stations sustain damage, there is a reduced chance of responders being able to promptly put out fires. Additionally, major incidents require a greater allocation of resources, leaving smaller fires and issues with little or inadequate attention in the initial hours following a significant earthquake event. The associated loss of electricity can also lower water pressure, further impeding firefighting efforts. 4.3.8.2 Population The entire population of Rialto is vulnerable to an earthquake. Both indoor and outdoor environments can be hazardous during earthquakes, with collapsed buildings, falling equipment, and moving debris causing death and injury. Additionally, downed power lines, as well as broken water and gas lines, pose threats to human life.

101
2023 LOCAL HAZARD MITIGATION PLAN

4.3.8.3 Critical Facilities Every structure in the City is potentially at risk during an earthquake. While difficult to predict the exact amount of damage, the area could experience something similar to the Northridge Earthquake which caused an estimated $20 billion in damage. An earthquake can cause damage to structures, utilities, transportation routes, and communication resulting in loss of revenue and ability to provide emergency, essential, and non-essential services. In addition, recovery includes substantial debris removal issues and multiple building inspections. 4.3.8.4 Non-Critical Facilities Specific non-critical facilities vulnerable in the City of Rialto include various residential and commercial properties, social service agencies, and government resources. While difficult to predict the exact amount of damage, the area could experience something similar to the Northridge Earthquake which caused an estimated $20 billion in damage. 4.3.8.5 Environment There are no major discrete environmental impacts from earthquakes. The ecology of California is well-adapted to them. 4.3.8.6 Future Trends in Development Future development is expected to be subject to new and more stringent codes to enhance resilience to earthquakes. This may eventually start to reduce overall vulnerability as the mix of buildings shifts. 4.3.9 Infectious Disease 4.3.9.1 Overall Vulnerability and Impact The vulnerability of a population to epidemic or pandemic is affected by several variables, including virus type, affected demographics, and environmental factors such as seasonality and individual medical conditions. While the Spanish Flu of 1920 impacted largely healthy young people, the COVID-19 pandemic was most impactful for elderly individuals, with morbidity and mortality rates highest among those aged 65 and older, particularly those 85 and older.

102
2023 LOCAL HAZARD MITIGATION PLAN
The economy can be Impacted by Infectious disease outbreaks through measures such as limiting travel and public events, and closing non-essential businesses, creating a high demand for healthcare resources. 4.3.9.2 Population The entire population of the City of Rialto is vulnerable to infectious disease. Most diseases impact certain segments of the population more than others; COVID-19 disproportionally affected the elderly and others with existing co-morbidities. Unhoused people with limited access to medical care would be disproportionally impacted as well. 4.3.9.3 Critical Facilities Infectious disease does not directly impact physical infrastructure. It would, however, impact staffing and human systems that support the physical infrastructure of the City. 4.3.9.4 Non-Critical Facilities Infectious disease does not directly impact physical infrastructure. It would, however, impact staffing and human systems that support the physical infrastructure of the City. 4.3.9.5 Environment Infectious disease does not directly impact the natural environment. 4.3.9.6 Future Trends in Development Infectious disease does not directly bear on development. However, future code updates such as mandating improved ventilation in buildings may make an impact. After the Spanish Flu, much of what became known as “modern” architecture, including increased use of light and space inside buildings, was informed by the experiences of the Spanish Flu. Something similar could be an effect of the COVID-19 pandemic. 4.3.10 Floods 4.3.10.1 Overall Vulnerability and Impact The average elevation of Rialto slopes steadily downward from its northern neighborhoods, leading to a natural slope that water will follow. Many of the flows are surface flows relying on the city curb

103
2023 LOCAL HAZARD MITIGATION PLAN
and gutter system which are easily overran by the volume of water running from the north to the south through the city street network. An expanded drainage way going north-south down Cactus has recently been expanded to increase overall drainage capacity. 4.3.10.2 Population The extent and nature of property damage from floods depend on the velocity and depth of floodwaters. Swift floodwaters can carry away buildings and vehicles. Flood debris carried along by the waters can hit and damage infrastructure such as pipelines and bridges. Basement flooding and soil saturation from flood events can lead to significant damage from landslides. Most flood damage occurs from water penetrating materials that are vulnerable to loss, such as wood, insulation, wallboard, fabric, furnishings, floor coverings, and appliances. In some cases, flood damage can make homes unlivable. 4.3.10.3 Critical Facilities During heavy rain events, stormwater can quickly overwhelm the capacity of storm drains, leading to flooding in streets and neighborhoods. This excess water can also flow into the sewer system, causing it to become overloaded and leading to backups and overflows. In addition, stormwater runoff can carry pollutants, such as debris, trash, chemicals, and sediment, into the sewer system. These pollutants can cause blockages and damage to pipes and equipment, as well as pose a risk to human health and the environment. 4.3.10.4 Non-Critical Facilities. Excessive storm debris may build up at upstream culverts, blocking the water flow and permitting the water to become un-channelized and overtopping the roadway at each location. In that instance, the waters may overtop each roadway, preventing the ingress and egress of emergency vehicles, between the east and west sides of the channel. In severe storm events there is the possibility that the flow may be excessive. Expected results would include possible undercutting and failure of roadway surfaces, washout of stream banks or embankments adjacent to the channel, or sheet flooding in adjacent residential neighborhoods with some levels of inundation depending on the location of individual properties. It is expected that most sheet flows within residential areas may be more nuisance type flows but are generally not expected to cause damage other than interior mudflows. Additional hazards may include vehicles that may attempt to cross these flooded locations and may stall or be swept away into the channel with possible resulting injury or loss of life due to vehicle entrapment. 4.3.10.5 Environment

104
2023 LOCAL HAZARD MITIGATION PLAN
Any sustained flooding event is likely to impact the City’s natural environment by potentially putting stress on aging trees and vegetation. 4.3.10.6 Future Trends in Development Impacts by future trends in development to flooding vulnerability will vary by how development occurs. Enhanced codes governing development and potential retrofitting of existing buildings and infrastructure may mitigate increasing vulnerability from changing climate conditions. 4.3.11 Heavy Rain 4.3.11.1 Overall Vulnerability and Impact The City of Rialto may experience local drainage issues, particularly in areas where stormwater runoff enters culverts or flows underground into storm drains. Poor maintenance of these drains may also contribute to flooding hazards in urban areas. 4.3.11.2 Population Rialto’s city limits incorporate a small portion of the Santa Ana River and its attendant floodplain. As is not unusual for a small river in California, the riverbed itself is largely dry for significant parts of the year, except during the rainy season. As housing prices have increased since the 2009 housing crash, southern California property values have increased. While Rialto is still relatively affordable compared to many other communities, Rialto has also seen an increase in its unhoused and transient populations. Encampments close to the Santa Ana River have developed, with cars and sometimes semi-permanent structures being erected. Estimates as to how many people live in these encampments are hard to make, but a visual examination reveals large numbers of vehicles, tents, and other items, with at least dozens and potentially hundreds of people residing there. An extreme flash flooding event caused by an atmospheric river, or a rain bomb becomes more likely over time because of climate change, even as overall conditions may become drier. Many inhabitants of the encampments may not get early warnings to evacuate or may not be able to. The potential for significant loss of life is high in the worst-case scenario. 4.3.11.3 Critical Facilities

105
2023 LOCAL HAZARD MITIGATION PLAN
Flash flooding can cause damage to structures, utilities, transportation routes, and communication resulting in loss of revenue and ability to provide emergency, essential, and non-essential services. In addition, recovery includes substantial debris removal issues and multiple building inspections. 4.3.11.4 Non-Critical Facilities The specific Non-Critical Facilities vulnerable in the City of Rialto include various smaller commercial and residential properties. Property damage caused by heavy rain and flooding events can vary depending on the depth and velocity of the rainfall. Although some events may not reach the level of a 100-year flood, they can still pose a serious threat, potentially washing away buildings from their foundations and sweeping away cars. Infrastructure such as pipelines and bridges are also at risk, as flood debris carried by high waters can cause extensive damage upon impact. Soil saturation from flood events can also lead to landslide damage and basement flooding, resulting in further property damage. Most flood damage is caused by water saturating materials that are susceptible to loss, such as wood, insulation, wallboard, fabric, furnishings, floor coverings, and appliances. In many cases, flood damage to homes can render them uninhabitable. 4.3.11.5 Environment Heavy rain and storms may kill trees and damage other vegetation. Otherwise, the impact on the natural environment alone is not significant. 4.3.11.6 Future Trends in Development It is unknown precisely how future trends in development would impact this vulnerability. New code standards encouraging use of permeable paving materials and otherwise reducing the overall impermeability of the surface area of the City as well as increasing the ability of the ground to absorb water would have a positive impact in reducing vulnerability. As storms grow in intensity and, paired with longer drought periods reducing overall absorptive capacity making more water stay on the surface longer, looking to new and innovative solutions to reduce the impacts of these events will become more necessary. 4.3.12 Severe Wind 4.3.12.1 Overall Vulnerability and Impact

106
2023 LOCAL HAZARD MITIGATION PLAN
Residential and commercial structures with weak reinforcement are vulnerable to windstorm damage. Wind pressure can push walls, doors, and windows inward, while passing currents create suction forces that pull building components and surfaces outward. Extreme wind forces can cause a building or its roof to fail, resulting in significant damage. In addition, even winds of 45 mph can cause tree limbs to become flying debris and damage structures. Overhead power lines can also be damaged and falling trees can bring electric power lines down to the pavement, creating a risk of electric shock. With rising population growth and new infrastructure in the region, the probability of windstorm damage is higher as more life and property are exposed to risk. Windstorms can cause damage to buildings, block roads and bridges, and damage traffic signals, streetlights, and parks, among other things. The inability to access emergency services due to blocked roads can limit the response operations during a windstorm, while industry and commerce can suffer losses from interrupted electric services and extended road closures. Such losses to buildings, personnel, and equipment, as well as service interruptions, may impact the local economy following a windstorm event. 4.3.12.2 Population Very few injuries to people are recorded during the types of high winds that Southern California experiences. Most damage is to property, but roads blocked by fallen trees during a windstorm may have severe consequences to people who need access to emergency services. In the event of a windstorm or microburst, emergency personnel may be required to respond to damage sustained by both residential and commercial structures, especially those with weak reinforcement. As discussed earlier, wind pressure and suction forces can cause damage to a building's components and surfaces, potentially causing the roof or entire building to fail. The debris carried by extreme winds can contribute to loss of life and failure of protective building elements. Downed trees, power lines, and damaged property can hinder emergency response and disaster recovery efforts. 4.3.12.3 Critical Facilities. All critical facilities are at risk for damage from severe winds which can damage structures, roads, traffic signals, and streetlights. Falling trees have been a leading cause of power outages. Windstorms, including strong microbursts and Santa Ana winds, can result in flying debris and downed utility lines. Even in minor windstorm events, tree limbs can break in winds as low as 45 mph and be thrown over 75 feet, causing damage to overhead power lines. This can result in electric power lines falling to the ground, posing a potential risk of fatal electric shock. 4.3.12.4 Non-Critical Facilities. All Non-Critical Facilities are at risk for damage from severe winds.

107
2023 LOCAL HAZARD MITIGATION PLAN
Strong windstorms can affect local transportation by causing trees and electrical wires to fall onto streets and highways, leading to road closures. During periods of very strong winds, major highways may also be temporarily closed to trucks and recreational vehicles. However, these disruptions are usually short-lived and do not have a significant long-term economic impact on the region. 4.3.12.5 Environment Strong winds may down trees, including those in City parks or street trees that provide shade for pedestrians. 4.3.12.6 Future Trends in Development Future development is unlikely to impact overall vulnerability to high winds, other than increased code requirements for new buildings and retrofits of existing structures. Maintaining a consistent tree care and planting program will be important to maintaining the health of the overall tree canopy in the face of threats from wind events.

108
2023 LOCAL HAZARD MITIGATION PLAN
Section 5 – Capability Assessment Element C: Mitigation Strategy Requirements C1. Does the plan document each jurisdiction’s existing authorities, policies, programs and resources and its ability to expand on and improve these existing policies and programs? (Requirement 44 CFR § 201.6(c)(3)) C2. Does the plan address each jurisdiction’s participation in the NFIP and continued compliance with NFIP requirements, as appropriate? (Requirement 44 CFR § 201.6(c)(3)(ii)) A capability assessment is an in-depth look at community mechanisms (such as plans, codes, ordinances, staffing, etc.) in place to support proposed mitigation activities. Performing the capability assessment helps communities identify regulatory, administrative, technical, and fiscal capacities and capabilities, and to consider ways that these tools can be used to further hazard mitigation and disaster resiliency goals. 5.1 – Planning and Regulatory Capabilities The city of Rialto has several planning and regulatory tools that can be used to support hazard mitigation and disaster preparedness efforts. These tools can be implemented at various levels, including the city's general plan, zoning regulations, building codes, and emergency management plans. The City has many opportunities for improvement in its planning capabilities described in Section 6, Mitigation Strategies. Not discussed there is the need for greater continuity of knowledge within existing City departments. Turnover of executives, managers and personnel working for the City has at times been high, with departures disrupting existing institutional knowledge as well as making it difficult to drive projects from beginning to end. Closer coordination for regional planning with neighboring cities as well as San Bernardino county may become increasingly necessary as natural hazard impacts intensify and grow beyond city boundaries. As part of the process of updating the hazard mitigation plan, the team reviewed and updated any planning and regulatory capabilities in documents provided to the team as well as interviews with City staff. Links to specific planning and regulatory tools are included in the table below.

109
2023 LOCAL HAZARD MITIGATION PLAN
Policy and Regulatory Resources
Administrative and Staff Resources
Policy and Regulatory Resources Link / Location Building Code https://library.municode.com/ca/rialto/codes/code_of_ordinances?nodeId=TIT15BUCO Capital Improvement Program https://www.yourrialto.com/380/Capital-Improvement-Program Comprehensive/General Plan https://www.yourrialto.com/653/General-Plan Economic Development Plan https://www.yourrialto.com/240/Economic-Development Erosion Management Ordinance https://library.municode.com/CA/rialto/codes/code_of_ordinances?nodeId=TIT17SU_CH17.40GRERCO Floodplain Management Ordinance https://library.municode.com/ca/rialto/codes/code_of_ordinances?nodeId=TIT18ZO_CH18.75FLMAOR Stormwater Management https://www.yourrialto.com/466/Environment Subdivision Regulation https://library.municode.com/ca/rialto/codes/code_of_ordinances?nodeId=TIT17SU Zoning https://library.municode.com/ca/rialto/codes/code_of_ordinances?nodeId=TIT18ZO Administrative and Staff Resources Link / Location Planning Commission https://www.yourrialto.com/570/Planning-Commission Building & Safety / Inspections https://www.yourrialto.com/192/Building-Safety-Division Emergency Services & Mutual Aid Compacts https://www.yourrialto.com/472/Emergency-Management Police Department https://rialtopolice.com/
Fire Department https://www.yourrialto.com/233/Fire-Department Planning Department https://www.yourrialto.com/265/Planning-Division Maintenance and Facilities - Environment https://www.yourrialto.com/466/Environment

2023 LOCAL HAZARD MITIGATION PLAN

111
2023 LOCAL HAZARD MITIGATION PLAN

5.2 – Fiscal Capability The City of Rialto’s budget is predominantly funded through property and sales tax. Police and Fire Department expenditures account for greater than 50% of the overall expenditures within the City budget. In terms of its financial ranking among similar communities in California, the city of Rialto falls in the middle range in terms of its fiscal health. The California State Auditor's Office produces an annual ranking of the fiscal health of California cities, based on a variety of factors such as liquidity, debt burden, and pension obligations. In the most recent report, Rialto was ranked 312th out of 471 cities in terms of its overall fiscal health, which puts it in the middle of the pack compared to other cities in the state. One factor that has contributed to Rialto's improved fiscal solvency is its efforts to reduce its debt burden. In recent years, the city has taken steps to pay down its debt and reduce its reliance on debt financing, which has helped to improve its credit rating and reduce its overall financial risk. The city has also implemented several cost-saving measures, such as consolidating services, to help balance its budget and reduce expenses. This puts Rialto on a firmer financial footing than many comparable communities and allows more solid fiscal planning for public safety and hazard mitigation. Rialto can apply for funding under FEMA programs such as the Hazard Mitigation Grant Program (HMGP) or the Building Resilient Infrastructure in Communities (BRIC) program Another potential source of funding for hazard mitigation projects is through the Community Development Block Grant (CDBG) program, administered by the Department of Housing and Urban Development (HUD). This program provides funding to local communities for a variety of projects, including those related to hazard mitigation. The city of Rialto can apply for CDBG funding to implement projects such as drainage improvements, erosion control, or wildfire fuel reduction. The city of Rialto can also consider issuing bonds to fund hazard mitigation projects. These bonds would be repaid over time through property taxes or other revenue sources and would allow the city to implement projects such as retrofitting critical infrastructure, building fire breaks, or developing early warning systems. Through instruments like resilience bonds, emergency reserves funds, contingency credit, parametric and risk transfer insurance, Rialto can support responsive capabilities even in financially debilitating disaster aftermaths. Building funds access for long-term recovery preserves economic viability essential for both near-term responsive capacity and continued climate adaptation progress despite shock events.

112
2023 LOCAL HAZARD MITIGATION PLAN
2023 LOCAL HAZARD MITIGATION PLAN
Finally, the city of Rialto can partner with other organizations and agencies to fund hazard mitigation projects. For example, the city can work with local businesses or non-profits to fund projects such as emergency preparedness education or the development of community-wide evacuation plans. 5.3 – Education and Outreach Capability Rialto’s police and fire departments are the City’s most citizen-facing departments, and as such have the greatest capability for education and outreach relating to hazard mitigation. The Police Department holds periodic public safety meetings in various parts of the city that are ideal settings for discussions and education on hazard mitigation measures. Police and, to a lesser extent, fire department outreach in the schools and other community settings can be easily oriented toward supporting hazard mitigation. The City also has several media distribution outlets, including a social media presence and Rialto TV, a public access channel. This would allow the city to both push relevant content and solicit citizen feedback in a much larger context yet at lower costs than public meetings. By participating in pilot programs for advanced hazard alerts leveraging real-time sensor data and AI, residents and emergency managers alike gain valuable extra hours responding to imminent disaster threats. Rialto can also explore expansion of key flood, storm surge, fire, and wind barriers to protect priority zones. Combined, enhanced foresight and defensive measures limit damages. Community-level disaster preparedness and recovery capacity increases resilience citywide. Rialto can create regular public education campaigns around hazard threats, appropriate emergency responses, usage of alerts systems, and access to support resources before and after crises. Recruiting local leaders into working groups also roots efforts in resident needs. Special events include: - At every important City event Public Safety have a pop-up education event handing out emergency management and preparedness educational materials. - City Police Department Community Meetings – attend meetings and provide handout preparedness and education information. - City employees attend clubs and engagements providing information and readiness for emergency management events.

113
2023 LOCAL HAZARD MITIGATION PLAN
- Annually the Fire Department puts on an open house in the Fire Department highlighting fire prevention week incorporation many elements of emergency management preparedness. - The City is current revising our CERT training. - 5.4 – National Flood Insurance Program Participation The City of Rialto currently participates in the National Flood Insurance Program and has participated since 1979.

CID Community Name County Init FHBM Identified Init FIRM Identified Curr Eff Map Date Reg-Emer Date Tribal 060280E RIALTO, CITY OF SAN BERNARDINO COUNTY 6/7/74 3/18/96 9/2/16 2/12/79 No In May 2023, new preliminary flood maps were delivered to communities within San Bernardino County, including Rialto. The County has authority over most floodplains affecting the City. Areas such as the Lytle Creek runoff, Interstate I-210 Channel, and the Rialto Channel south of the I-10 are opened only when the County deems fit. • Adoption of NFIP minimum floodplain management criteria via local regulation. Adoption and floodplain management for the city’s northeastern floodplain is through the San Bernardino Flood Control District (SBCFCD). • Adoption of the latest effective Flood Insurance Rate Map (FIRM). Adoption and floodplain management for the cities northeastern floodplain is through the San Bernardino Flood Control District (SBCFCD). • Implementation and enforcement of local floodplain management regulations to regulate and permit development in SFHA’s. There are no portions of the City of Rialto that are within an SFHA. • Appointment of a designee or agency to implement the addressed commitments and requirements of the NFIP. The City of Rialto’s Planning Department is responsible for implementing the addressed commitments and requirements of the NFIP. • Description of how participants implement the substantial improvement/substantial damage provisions of their floodplain management

114
2023 LOCAL HAZARD MITIGATION PLAN
2023 LOCAL HAZARD MITIGATION PLAN
regulations after an event. The City of Rialto’s Planning Department will implement all applicable provisions after a flood event. • Repetitively-flooded NFIP-insured structures. There are no repetitively-flooded NFIP-insured structures within the City of Rialto.

115
2023 LOCAL HAZARD MITIGATION PLAN
Section 6 – Mitigation Strategy Element C: Mitigation Strategy Requirements C1. Does the plan document each jurisdiction’s existing authorities, policies, programs and resources and its ability to expand on and improve these existing policies and programs? (Requirement 44 CFR § 201.6(c)(3)) C2. Does the plan address each jurisdiction’s participation in the NFIP and continued compliance with NFIP requirements, as appropriate? (Requirement 44 CFR § 201.6(c)(3)(ii)) C3. Does the plan include goals to reduce/avoid long-term vulnerabilities to the identified hazards? (Requirement 44 CFR § 201.6(c)(3)(i)) C4. Does the plan identify and analyze a comprehensive range of specific mitigation actions and projects for each jurisdiction being considered to reduce the effects of hazards, with emphasis on new and existing buildings and infrastructure? (Requirement 44 CFR § 201.6(c)(3)(ii)) C5. Does the plan contain an action plan that describes how the actions identified will be prioritized (including cost benefit review), implemented and administered by each jurisdiction? (Requirement 44 CFR § 201.6(c)(3)(iii)); (Requirement 44 CFR § 201.6(c)(3)(iv)) The Mitigation Strategy serves as a comprehensive guide for the City of Rialto in its pursuit of enhancing disaster resilience by reducing vulnerability to identified hazards. Through the identification of specific Mitigation Goals and Objectives, strategies and initiatives are formulated to prevent, minimize, and alleviate the impacts of both natural and manmade disasters on the local population and property within the planning area. Strengthening community resilience involves the implementation of building codes, zoning ordinances, and other regulatory measures. During the review or update of these planning mechanisms, there is an opportunity to assess the feasibility of integrating mitigation strategies into policy changes. These proactive efforts contribute significantly to ensuring the City's sustained resilience in the face of hazard events. All new buildings and infrastructure have to comply with existing building codes and mitigation strategies. All plans for construction are reviewed by the Building and Safety Division and the Planning Division to ensure compliance with the Uniform Building Code, the General Plan, and City Ordinances.

116
2023 LOCAL HAZARD MITIGATION PLAN
2023 LOCAL HAZARD MITIGATION PLAN
The Hazard Mitigation Planning Team discussed the most likely hazards and potential mitigation projects at length in order to evaluate which mitigation activities would be most beneficial to the City. The team discussed modifying infrastructure, facilities, land use, seismic retrofitting, and updates to the General Plan and the Municipal Code. City Staff make recommendations to the Rialto City Council regarding prioritization and funding of the above and future projects, yet the decision lies ultimately with the Councilmembers. Capital Improvement Projects and other Mitigation Projects receive public hearings as either part of the budgeting process or as individual staff items for City Council which allows for public input. 6.1 Mitigation Goals and Objectives Goal 1: Reduce adverse impacts from natural and human-caused hazards. • Minimize the level of death, injury, property damage, economic and social dislocation, and disruption of vital services. • Protect critical facilities from damage, loss of function, or inaccessibility. • Reduce losses and repetitive damages for chronic hazard events. • Improve hazard assessment data and review processes to better understand hazard impacts. Goal 2: Ensure Effective Response of Emergency Services • Ensure that first responders and the Emergency Operations Center (EOC) have adequate capacity to respond to hazard events. • Coordinate and integrate hazard mitigation activities with emergency operations plans and procedures. • Cooperate with neighboring jurisdictions and internal departments to maximize public safety and emergency services. • Support existing mutual aid and automatic aid agreements for additional resources needed during an emergency. Goal 3: Coordinate and Maximize Resources to Support Hazard Mitigation • Strengthen communication among and within public agencies, citizens, non-profit organizations, business, and industry. • Encourage leadership to prioritize and implement hazard mitigation activities. • Identify, apply for, and utilize external sources of funding for mitigation programs.

117
2023 LOCAL HAZARD MITIGATION PLAN
• Prioritize mitigation and capital improvement projects, based on cost effectiveness for projects that promote protecting life, property, and the environment. • Examine alternative sources of support or financing for hazard mitigation. Goal 4: Increase Community Outreach and Connection to Support Hazard Mitigation • Develop and implement education and outreach programs to increase public awareness of the risk associated with natural hazards. • Provide information on education tools, partnership opportunities, and funding resources to assist in implementing mitigation activities. • Utilize existing and procure additional resources to adequately educate residents regarding hazard mitigation and emergency preparedness. Goal 5: Promote Nature-based Solutions and Preserve Natural Systems • Develop hazard mitigation strategies based on natural processes that enhance natural systems. • Balance natural resource management, and land use planning with natural hazard mitigation actions designed to protect life, property, and the environment. 6.2 Mitigation Action Plan This Plan presents a wide range of potential mitigation actions to increase the City of Rialto’s resilience to natural and human-caused disasters. The range of options is designed to give the City maximum flexibility in choosing strategies that are not only technically appropriate but feasible in a sometimes-shifting political environment. This flexibility is vitally important to make effective hazard mitigation possible in a practical sense. However, it must be balanced by defined evaluation criteria and a framework for pushing these actions forward. Options that are chosen for potential implementation will be subject to a cost-benefit review by the City to ensure their financial viability. They will also be evaluated by the following criteria: • Whether the action is foundational for other effective actions. • Downstream impacts – does the action have negative consequences inside or outside the City? • Institutional capacity and ability to support beyond initial implementation. • Equity – how does the action impact historically disadvantaged

118
2023 LOCAL HAZARD MITIGATION PLAN
2023 LOCAL HAZARD MITIGATION PLAN
populations • Future conditions – how does the action hold up under future natural conditions that are different than today?

119
2023 LOCAL HAZARD MITIGATION PLAN

6.3 Mitigation Actions Goal Hazard Vulnerability Action Description Responsible Department Funding Source Timeframe Goal 1: Emergency Response All Hazards Critical Infrastructure Area Monitors Personnel act as Area Monitors in City Facilities to assist with employee preparedness, including conducting monthly fire extinguisher checks, maintaining employee lists, practicing evacuations, and assisting the Community Safety Department with other preparedness and response activities.

Police & Fire Departments City of Rialto General Fund Annually Goal 1: Emergency Response All Hazards Critical Infrastructure Emergency Operations Center Equipment Update Emergency Operations Center equipment and supplies as necessary to ensure effectiveness. Police & Fire Departments City of Rialto General Fund Annually Goal 1: Emergency Response All Hazards Critical Infrastructure Emergency Operations Center Technology Periodically review technology used to support the Emergency Operations Center to ensure systems are updated and effective. Police & Fire Departments, Maintenance & Facilities City of Rialto General Fund Annually Goal 1: Emergency Response All Hazards Critical Infrastructure Emergency Operations Plan Continue to implement the Emergency Operations Plan, which functions as the City's manual for communication protocol in the events of disaster. Police & Fire Departments City of Rialto General Fund Annually Goal 1: Emergency Response All Hazards Critical Infrastructure EOC Drill Conduct annual EOC drill or exercise to provide City personnel with the opportunity to practice their responsibilities during an emergency. Police & Fire Departments City of Rialto General Fund Annually Goal 1: Emergency Response All Hazards Critical Infrastructure Mandatory NIMS/SEMS Refresher Conduct refresher trainings annually for all City personnel on NIMS and SEMS Police & Fire Departments City of Rialto General Fund Annually

120
2023 LOCAL HAZARD MITIGATION PLAN
Goal 1: Emergency Response All Hazards Critical Infrastructure, Non-Critical Infrastructure Back-up generators Provide back-up generators for critical facilities and schools Police & Fire Departments City of Rialto General Fund Not started; completion within one year Goal 1: Emergency Response All Hazards Critical Infrastructure, Non-Critical Infrastructure City Employee Disaster Training Provide training to all City employees on their roles and responsibilities in times of disasters and local emergencies. Training should include comprehensive and realistic disaster exercises, and cross-training for multiple potential roles should be considered.

Police & Fire Departments City of Rialto General Fund Annually Goal 1: Emergency Response All Hazards Critical Infrastructure, Non-Critical Infrastructure Earthquake Preparedness Drills Conduct emergency preparedness and response drills for mock major earthquake events-the natural hazards with the greatest potential for injury, life loss, property damage and service interruptions. Drills should test disaster response systems and communication protocols. When preparing the drills, consider the wide range of potential risks associated with critical facilities and vulnerabilities. Include City officials, utility providers, emergency response stakeholders and representatives of vulnerable facilities.

Police & Fire Departments City of Rialto General Fund Annually Goal 1: Emergency Response All Hazards Critical Infrastructure, Non-Critical Infrastructure Emergency Drill Conduct emergency drills and exercises to provide City personnel with the opportunity to practice their responsibilities during an emergency. Police & Fire Departments City of Rialto General Fund Annually Goal 1: Emergency Response All Hazards Critical Infrastructure, Non-Critical Infrastructure Mutual Aid Agreement Participation Continue to participate in Statewide Master Mutual Aid Agreements and local automatic aid agreements related to emergency response. Police & Fire Departments City of Rialto General Fund Annually Goal 1: Emergency Response All Hazards Critical Infrastructure, Non-Critical Infrastructure Update Continuity of Operations and Disaster Recovery Plans When needed because of changing City conditions, update the Continuity of Operations Plan and Disaster Recovery Plan. Police & Fire Departments City of Rialto General Fund As needed

121
2023 LOCAL HAZARD MITIGATION PLAN
Goal 1: Emergency Response All Hazards Non-Critical Infrastructure Employee Emergency Backpacks Issue all employees an emergency backpack and supplies are restocked annually. Police & Fire Departments City of Rialto General Fund Annually Goal 1: Emergency Response All Hazards Non-Critical Infrastructure Hazard Recovery Program Database Develop a repository of resources or case studies on relevant hazard recovery programs that could allow for nimble emergency ordinances, facilitate speedy recovery, and increase resilience for vulnerable populations. Police & Fire Departments City of Rialto General Fund Within three months after approval Goal 1: Emergency Response All Hazards Non-Critical Infrastructure Update and Maintain Geographic Information System (GIS) Program Capability Update and maintain City Geographic Information System (GIS) capacity and ensure coordination between planning, Police & Fire Departments, and emergency management. Maintenance & Facilities City of Rialto General Fund Annually Goal 1: Emergency Response All Hazards Population Accelerated Emergency Response for Vulnerable Populations Prioritize focused response efforts in the event of disaster to ensure the safety of persons in vulnerable or hard to access areas, as well as increase planning and response capabilities. Police & Fire Departments City of Rialto General Fund Ongoing Goal 1: Emergency Response All Hazards Population CERT Program Offer CERT training and courses for residents Police & Fire Departments City of Rialto General Fund Annually Goal 1: Emergency Response All Hazards Population, Non-Critical Infrastructure Emergency Preparedness and Resilience Campaigns Implement public education campaigns for residents and businesses about appropriate emergency preparedness measures and what to do in the event of a disaster. Develop special themes and topics to increase awareness of hazards.

Police & Fire Departments City of Rialto General Fund Annually Goal 2: Reduce Hazards Impact All Hazards Environment Green Space Networks Green space networks: Promote the development to a network of green spaces throughout the City, prioritizing areas with low park access. Community Development City of Rialto General Fund Ongoing

122
2023 LOCAL HAZARD MITIGATION PLAN
Goal 2: Reduce Hazards Impact All Hazards Environment, Critical Infrastructure, Non-Critical Infrastructure Sponge City Infrastructure - Normalize Water Cycle Flows Use "sponge city" concepts to increase water flow and reduce undesired retention (i.e., flooding) to work with water cycle and retain water where desired. Engineering Services City of Rialto General Fund and private developers New Goal 2: Reduce Hazards Impact All Hazards Environment, Non-Critical Infrastructure Environmental and Open-space Grants Pursue environmental and open-space grants on federal and state level for at-risk parcels to fire, flood, and other hazards. Community Development City of Rialto General Fund Ongoing Goal 2: Reduce Hazards Impact Cyberattack Critical Infrastructure City-wide Cybersecurity Strategy Update and implement citywide cyber-security strategy and operational plan to identify threats and vulnerabilities to all cyber systems (including , communications, signals, corporate data, security networks), and put operational plans in place to mitigate those threats and reduce vulnerabilities.

Maintenance & Facilities City of Rialto General Fund Ongoing Goal 2: Reduce Hazards Impact Cyberattack Critical Infrastructure Citywide Cybersecurity Awareness Program Risk reduction through employee education via training and awareness initiatives including classroom, computer-based training courses, anti-phishing simulation testing and training, various media initiatives, and role-based training for users with privileged access.

Maintenance & Facilities City of Rialto General Fund Ongoing Goal 2: Reduce Hazards Impact Cyberattack Critical Infrastructure IT Recovery Plan Create, distribute, and implement a recovery plan to ensure continuity of IT operations in the event of a disaster. Maintenance & Facilities City of Rialto General Fund Annually Goal 2: Reduce Hazards Impact Cyberattack Critical Infrastructure Simulated Cyberattacks to Understand Vulnerability Simulate cyberattacks including using "black-hat" intruders to understand and address cyber-vulnerabilities. Maintenance & Facilities City of Rialto General Fund Annually Goal 2: Reduce Hazards Impact Cyberattack Critical Infrastructure, Non-Critical Infrastructure Update Authentication Methods for IT Access Revise and update access to City networks. Maintenance & Facilities City of Rialto General Fund Ongoing

123
2023 LOCAL HAZARD MITIGATION PLAN
Goal 2: Reduce Hazards Impact Drought Future Impacts of Development, Non-Critical Infrastructure Incentives for Water-saving Appliances Provide incentives for households and businesses to install water-saving appliances. Engineering Services City of Rialto General Fund and private developers Ongoing Goal 2: Reduce Hazards Impact Drought Future Impacts of Development, Non-Critical Infrastructure Incentives for Water-saving Landscaping and Xeriscaping Provide incentives for households and businesses to install water-saving landscaping, including xeriscaping. Engineering Services City of Rialto General Fund and private developers Ongoing Goal 2: Reduce Hazards Impact Drought Future Impacts of Development, Non-Critical Infrastructure Water Recycling for Non-Potable Uses Use of greywater or recycled water for non-drinking water uses wherever possible. Engineering Services City of Rialto General Fund Ongoing Goal 2: Reduce Hazards Impact Earthquake Critical Infrastructure Participation in Great California Shakeout Drill Annually, participate in the Great California Shakeout Drill at City Hall and provide prizes for participation Police & Fire Departments City of Rialto General Fund Annually Goal 2: Reduce Hazards Impact Earthquake
Critical Infrastructure, Future Impacts of Development, Non-Critical Infrastructure Earthquake Insurance for All City Facilities Secure earthquake insurance for all City facilities. Finance City of Rialto General Fund Annually Goal 2: Reduce Hazards Impact Earthquake
Critical Infrastructure, Future Impacts of Development, Non-Critical Infrastructure Renovations and Retrofits Require seismic retrofits for major renovations. Additionally, when supporting revitalization or rehabilitation of substandard housing, require seismic retrofits as needed, such as for unreinforced masonry buildings. Community Compliance City of Rialto General Fund and private developers Ongoing

124
2023 LOCAL HAZARD MITIGATION PLAN
Goal 2: Reduce Hazards Impact Earthquake
Critical Infrastructure, Future Impacts of Development, Non-Critical Infrastructure Require Geotechnical Investigations for Relevant Projects Require geotechnical investigations by certified engineering geologist or other qualified professionals for all grading and construction projects subject to geologic hazards, including fault rupture, severe ground shaking, liquefaction, landslides, and collapsible or expansive soils.

Community Development City of Rialto General Fund and private developers Ongoing Goal 2: Reduce Hazards Impact Earthquake Critical Infrastructure, Non-Critical Infrastructure Earthquake Action Plan Prepare earthquake action plan identifying most vulnerable infrastructure/utilities and planning emergency routes bypassing the infrastructure if damaged. Provides the ability to move emergency management personnel to help residents after an earthquake.

Police & Fire Departments, Engineering Services City of Rialto General Fund Ongoing Goal 2: Reduce Hazards Impact Earthquake Critical Infrastructure, Non-Critical Infrastructure Earthquake Preparedness Encourage reduction of nonstructural and structural earthquake hazards in homes, schools, businesses, and government offices Community Development City of Rialto General Fund Ongoing Goal 2: Reduce Hazards Impact Earthquake Future Impacts of Development Earthquake Code Compliance Require all construction to be in conformance with the Uniform Building Code (UBC) and the California Building Code (CBC), and to be consistent with the Municipal Code as it provides for earthquake resistant design, excavation, and grading.

Community Development City of Rialto General Fund Ongoing Goal 2: Reduce Hazards Impact Extreme Heat Environment Street Tree Planting Prioritize tree planting from approved street tree list based on the existing tree canopy and the population’s vulnerability to extreme heat. Where possible, integrate shade trees with bike and pedestrian infrastructure. Community Development City of Rialto General Fund Ongoing Goal 2: Reduce Hazards Impact Extreme Heat Environment Tree Trimming and Health Checks Prune street trees regularly in residential areas and along commercial streets. Have regular tree health checks by certified arborists. Engineering Services City of Rialto General Fund As needed

125
2023 LOCAL HAZARD MITIGATION PLAN
Goal 2: Reduce Hazards Impact Extreme Heat Environment Urban Tree Canopy Develop a program and funding mechanisms to increase and maintain the urban tree canopy, prioritizing neighborhoods with low tree canopy coverage and/or high urban heat island effect. Community Development City of Rialto General Fund and other mechanisms to be determined Ongoing Goal 2: Reduce Hazards Impact Extreme Heat Environment, Non-Critical Infrastructure Cool/Green/White Roofs Explore the feasibility of incentivizing cool and/or green roofs for existing residential and existing/new commercial, industrial, institutional, and similar structures in the City. Develop user-friendly standards that clearly explain the process and requirements for incorporating cool roof systems in the City and train all relevant personnel in processes and requirements. Consider developing and implementing a white roof project, modeled after New York City’s in the communities most highly burdened by heat island impacts. Incentivize attic thermal insulation in all rental units.

Community Development City of Rialto General Fund and private developers New Goal 2: Reduce Hazards Impact Extreme Heat Population Public Education Programs Develop public education programs for what to do during extreme heat events and how to stay safe and hydrated. Police & Fire Departments City of Rialto General Fund Ongoing Goal 2: Reduce Hazards Impact Extreme Heat Population, Non-Critical Infrastructure Cooling Centers Develop and expand designated network of cooling centers for use during extreme heat events. Cooling centers should remain open late into the evening when the temperature remains high. Police & Fire Departments City of Rialto General Fund Ongoing Goal 2: Reduce Hazards Impact Extreme Heat Population, Non-Critical Infrastructure Generator Backup for Air Conditioning Systems in Cooling Centers and Backup City Facilities Ensure generator backup for air conditioning systems exists for all cooling centers and City facilities that might be used as backup cooling centers. Engineering Services City of Rialto General Fund Ongoing

126
2023 LOCAL HAZARD MITIGATION PLAN
Goal 2: Reduce Hazards Impact Flood
Critical Infrastructure, Future Impacts of Development, Non-Critical Infrastructure Storm Drain Master Plan update & review Review and update stormwater plans; communicate recommendations to planning and emergency management departments Engineering Services City of Rialto General Fund Annually Goal 2: Reduce Hazards Impact Flood
Critical Infrastructure, Future Impacts of Development, Non-Critical Infrastructure Stormwater Infrastructure as part of capital improvement updates Update stormwater infrastructure as identified in City's capital improvement program. Engineering Services City of Rialto General Fund Annually Goal 2: Reduce Hazards Impact Flood Future Impacts of Development, Non-Critical Infrastructure Flood Infrastructure and Drainage Projects In Conjunction with Road Construction / Expansion For all future road expansion or construction, integrate flood control infrastructure and where possible nature-based solutions (swales, etc.) Engineering Services City of Rialto General Fund/CalTrans & FHWA grants Ongoing Goal 2: Reduce Hazards Impact Flood Future Impacts of Development, Non-Critical Infrastructure Promote Permeable Surfaces and Water Flow
Design new developments with water retention structures and permeable surfaces to minimize flooding of the surface drainage system by peak flows. Consider the potential for larger-scale capture via diversion to large-scale spreading grounds or other options on a site-by-site basis.

Engineering Services City of Rialto General Fund and private developers Ongoing Goal 2: Reduce Hazards Impact Flood Future Impacts of Development, Non-Critical Infrastructure Sewer Root Control Annually treat approximately 20% of the citywide sewer system with herbicide to retard tree root intrusion. This prevents sewer blockages and overflows which are a health and safety emergency. Engineering Services City of Rialto General Fund Annually

127
2023 LOCAL HAZARD MITIGATION PLAN
Goal 2: Reduce Hazards Impact Flood Future Impacts of Development, Non-Critical Infrastructure Update Engineering Standards considering Climate Change and More Extreme Rainfall Update engineering standards for water infrastructure to handle increased stress from extreme weather and climate events. Engineering Services City of Rialto General Fund Annually Goal 2: Reduce Hazards Impact Flood Non-Critical Infrastructure Drain Maintenance and Clearance Maintain routine maintenance of down and bench drains in and around residential and commercial areas to avoid accumulation of debris which could lead to dangerous and destructive flooding. Engineering Services City of Rialto General Fund Ongoing Goal 2: Reduce Hazards Impact Hazardous Materials Environment, Population Spill Control Packages in City Vehicles Allows for faster clean-up to protect the citizens and environment. Engineering Services City of Rialto General Fund New Goal 2: Reduce Hazards Impact Hazardous Materials Non-Critical Infrastructure Hazardous Materials User Inventory Identify hazardous material users and generators within the City using field surveys, inspection programs, and licensing requirements. Engineering Services City of Rialto General Fund New Goal 2: Reduce Hazards Impact Infectious Disease Critical Infrastructure, Population Digital Infrastructure Upgrades for Pandemic Maintain and update IT systems regularly in case of sudden need for remote work. Maintenance & Facilities City of Rialto General Fund Ongoing Goal 2: Reduce Hazards Impact Infectious Disease Population Pandemic Planning Review pandemic response and history and proactively plan based on lessons learned for future pandemics. Police & Fire Departments City of Rialto General Fund Ongoing Goal 2: Reduce Hazards Impact Infectious Disease Population Personal Protective Equipment (PPE) Storage and Maintenance Maintain store of usable PPE in case of pandemic event. Police & Fire Departments City of Rialto General Fund Ongoing Goal 2: Reduce Hazards Impact Power Outages Critical Infrastructure Remote Work Pre-planning Develop plans to support remote work during hazard events. Ensure connectivity and strategic dispersal of key personnel. Maintenance & Facilities City of Rialto General Fund Ongoing

128
2023 LOCAL HAZARD MITIGATION PLAN
Goal 2: Reduce Hazards Impact Power Outages Critical Infrastructure Storm Hardening to Prevent Power Outages Storm hardening for critical power and utility facilities Engineering Services City of Rialto General Fund Ongoing Goal 2: Reduce Hazards Impact Power Outages Critical Infrastructure, Non-Critical Infrastructure Microgrids and Redundancy Structuring Isolate partial outages to smallest areas possible Engineering Services City of Rialto General Fund Ongoing Goal 2: Reduce Hazards Impact Power Outages Critical Infrastructure, Non-Critical Infrastructure Renewable Energy for Power Outages Renewable energy for City infrastructure to reduce dependence on grid and susceptibility to broader power outages. Engineering Services City of Rialto General Fund New Goal 2: Reduce Hazards Impact Power Outages Critical Infrastructure, Non-Critical Infrastructure, Population Power Capacity Adjustment for High-Risk Heat Days
Explore capacity of adjusting power capacity and redundancy during extreme heat events to increase capacity of grid to run air conditioning. Engineering Services City of Rialto General Fund Ongoing Goal 2: Reduce Hazards Impact Power Outages Future Impacts of Development, Non-Critical Infrastructure Encourage New Construction and Retrofit Consideration of Cooling Without Power Encourage new construction to include porches, openable windows, and other structural methods to allow cooling without power. Explore a retrofit program to do the same for existing buildings. Community Development City of Rialto General Fund and private developers New Goal 2: Reduce Hazards Impact Severe Wind Environment Windstorm Preparedness Maintain local City and utility awareness of tree pruning and code sections relevant to wind-resistant utility operations Engineering Services City of Rialto General Fund Ongoing Goal 2: Reduce Hazards Impact Terrorism Non-Critical Infrastructure Advertised First Aid Caches around City Locate first aid caches around the City, especially at public gathering places, to reduce time immediate medical care could be given during an event Police & Fire Departments City of Rialto General Fund Within three months after approval Goal 2: Reduce Hazards Impact Terrorism Population Emergency Planning for Events Create standard operating procedures and regularly update for potential terrorist or active assailant events. Police & Fire Departments City of Rialto General Fund New

129
2023 LOCAL HAZARD MITIGATION PLAN
Goal 2: Reduce Hazards Impact Terrorism Population Improved Predictive Threat Methods Software-based analysis to understand both potential events and potential perpetrators. Police & Fire Departments City of Rialto General Fund New Goal 2: Reduce Hazards Impact Wildfire Population Analysis of Smoke Impacts and Mitigation Conduct analysis of smoke impacts, trajectory, and best mitigation methods. Fire Department City of Rialto General Fund Within one year after approval Goal 2: Reduce Hazards Impact Wildfire Population Provide Air Filters to Low-Income Residents Provide air filtration equipment to low-income residents at low or no charge. Police & Fire Departments City of Rialto General Fund New Goal 3: Maximize Resources All Hazards Critical Infrastructure Designate Hazard Mitigation Coordinator to Drive LHMP Implementation Designate a Hazards Mitigation Coordinator to oversee LHMP implementation. Police & Fire Departments City of Rialto General Fund Ongoing Goal 3: Maximize Resources All Hazards
Critical Infrastructure, Future Impacts of Development, Non-Critical Infrastructure Issuing Special-Purpose Bonds Issue resilience/green infrastructure bonds or other special-purpose financial instruments. Finance City of Rialto General Fund and financial markets New Goal 3: Maximize Resources All Hazards
Critical Infrastructure, Future Impacts of Development, Non-Critical Infrastructure Public-Private Partnerships Pursue public-private partnerships for resilience funding, especially in industrial areas or with new development. Finance City of Rialto General Fund and private developers Ongoing

130
2023 LOCAL HAZARD MITIGATION PLAN
Goal 3: Maximize Resources All Hazards Critical Infrastructure, Non-Critical Infrastructure Funding Options for Hazards Mitigation Conduct survey of disaster risk reduction and adaptation funding options for the City. Options could include special taxing districts, private/philanthropic sources, and others.

Police & Fire Departments, Community Development City of Rialto General Fund Annually Goal 3: Maximize Resources All Hazards Critical Infrastructure, Non-Critical Infrastructure Program Cycle Management and Data Collection for Disaster Risk Reduction Collect data and develop program methodology to adaptively manage hazard mitigation through examination of hazard events. Police & Fire Departments City of Rialto General Fund Every 5 years Goal 3: Maximize Resources All Hazards Environment, Non-Critical Infrastructure Green Streets Program Develop a green streets program to support a sustainable approach to stormwater, drainage, groundwater recharge, and landscaping and incorporate green streets standards and guidelines in all streetscape improvements. Engineering Services City of Rialto General Fund/CalTrans & FHWA grants Annually Goal 3: Maximize Resources All Hazards Future Impacts of Development Adoption of new City building codes Adoption of new City building code approximately every three years: Includes updating seismic and structural requirements. Electrification efforts should include language on hardening grid and power systems as well as promoting resilience to disasters and distributed energy generation (solar, etc.). Attic insulation should be required in existing rental units.

Community Development City of Rialto General Fund Every 3 years.

131
2023 LOCAL HAZARD MITIGATION PLAN
Goal 3: Maximize Resources All Hazards Future Impacts of Development Code Enforcement Enforce all applicable and current building & land use codes and ordinances. Adopt and develop new codes and standards that provide protection beyond minimum standards. Develop partnerships with business community to develop and maintain businesses with emphasis on pre-mitigation practices. Continue efforts to replace non-reinforced masonry buildings through safety inspections and business licensing process. Continue efforts to ensure that Critical facilities meet minimum building code standards for seismic and critical events. The overall goal is to minimize deaths and injuries that could be caused by the impact from a disaster.

Community Development City of Rialto General Fund Every 3 years Goal 3: Maximize Resources All Hazards Future Impacts of Development, Non-Critical Infrastructure Community Insurance Promotion Promote uptake of disaster insurance; consider community-embedded insurance or other new disaster insurance models. Finance City of Rialto General Fund New Goal 3: Maximize Resources All Hazards Future Impacts of Development, Non-Critical Infrastructure Leverage Development for Resilience Investment Require developers to implement resilience measures through impact fees, tax increment financing, or other mechanisms. Community Development City of Rialto General Fund Every 3 years Goal 3: Maximize Resources All Hazards Non-Critical Infrastructure Public WiFi Power Backup Ensure battery backup at critical city facilities, including parks. Engineering Services City of Rialto General Fund New

132
2023 LOCAL HAZARD MITIGATION PLAN
Goal 3: Maximize Resources All Hazards Non-Critical Infrastructure Road Repair and Enhancement Repave roadways, fix broken and damaged sidewalks, upgrade traffic signal equipment, install ADA ramps at the corners of streets, add landscaped medians and storm drain catch basins at locations. When possible and deemed necessary, or during regular road maintenance, upgrade existing roads to meet minimum road widths, surface, grade, radius, and turnarounds to ensure emergency vehicle access is possible.

Engineering Services City of Rialto General Fund Ongoing Goal 3: Maximize Resources All Hazards Population Financial Resources Post-Disaster Public awareness to have cash on hand in case of disaster; develop methods to deliver cash to survivors in a timely fashion. Police & Fire Departments, Communications City of Rialto General Fund New Goal 3: Maximize Resources Earthquake Future Impacts of Development, Non-Critical Infrastructure New Development Seismic Standards Evaluate and update seismic standards for all new development based on best practices and needs. Community Development City of Rialto General Fund Every 3 years Goal 3: Maximize Resources Extreme Heat Future Impacts of Development, Non-Critical Infrastructure Update Code to Require Air Conditioning Require air conditioning in all rental units. Community Development Private Funding (developers pay cost) Subsequent to City Council action
Goal 4: Public Understanding All Hazards Critical Infrastructure Community Forums for Sheriff/Fire Services Assessment and Community Engagement Communication forums between sheriff and fire department and the community to obtain community feedback regarding service, service needs and, to engage the community in crime prevention. Police & Fire Departments City of Rialto General Fund Ongoing

133
2023 LOCAL HAZARD MITIGATION PLAN
Goal 4: Public Understanding All Hazards Critical Infrastructure, Population Resilience Centers Supply cooling centers with refrigerators for storing medicine, backup water supplies, and social services information in multiple languages. Establish locations to provide disaster planning assistance and backup supplies and power sources. Backup power and outlets for personal device charging.

Police & Fire Departments City of Rialto General Fund Ongoing Goal 4: Public Understanding All Hazards Population Disaster Kit Distribution Work with local places of worship and local non-profits to create disaster kits for lower-income residents. This should include disaster supplies and guidance on how to collect and store important documents. Police & Fire Departments City of Rialto General Fund Annually Goal 4: Public Understanding All Hazards Population Encourage and Promote Community Networks and Groups Support programs such as Neighborhood Watch Organizations to build and train teams of community residents, leaders, and stakeholders to assist with emergency response and first aid. Make use of existing community networks to enlist participants.

Police & Fire Departments City of Rialto General Fund Annually Goal 4: Public Understanding All Hazards Population Know Your Neighbor Program Coordinate a Know Your Neighbor Program where community leaders and neighbors provide resources and check in on vulnerable populations during hazard events where people shelter at home. Police & Fire Departments City of Rialto General Fund Annually Goal 4: Public Understanding All Hazards Population Bilingual Outreach and Emergency Notifications Targeted, in-person outreach to Spanish speakers. Ensure any cellphone-based notification systems include Spanish. Police & Fire Departments, Communications City of Rialto General Fund Annually Goal 4: Public Understanding All Hazards Population Neighborhood Based Response Convene and regularly train neighborhood-based emergency response teams (e.g., CERT), incorporating climate change response and recovery. Ensure CERT recruiting includes a diverse set of community members and leaders.

Police & Fire Departments City of Rialto General Fund Annually Goal 4: Public Understanding All Hazards Population Police & Fire Departments Education Host public education programs to enhance Police & Fire Departments about fire safety and crime prevention as well as emergency preparedness Police & Fire Departments City of Rialto General Fund Annually

134
2023 LOCAL HAZARD MITIGATION PLAN
Goal 4: Public Understanding All Hazards Population Regular Needs Assessment Regularly meet with community leaders that represent special needs populations, including seniors, to maintain continuous two-way communication. This should include surveys and other needs assessments to refine notification and response policies.

Police & Fire Departments City of Rialto General Fund Annually Goal 4: Public Understanding All Hazards Population Socialize Emergency Preparedness Plans Distribute and/or publicize established emergency preparedness plans to increase public awareness. Consider development of translated plans, executive summaries, or policies and programs when feasible.

Police & Fire Departments, Communications City of Rialto General Fund Annually Goal 4: Public Understanding All Hazards Population Unhoused Population Outreach Outreach to unhoused populations; provide pathways to employment and housing in less-perilous areas. Police & Fire Departments, Communications City of Rialto General Fund Annually Goal 4: Public Understanding All Hazards Population Vulnerable Population Registry Develop a voluntary vulnerable population registry and subsequent priority list to help first responders better provide services and meet the needs of those most in need. Police & Fire Departments, Communications City of Rialto General Fund Annually

135
2023 LOCAL HAZARD MITIGATION PLAN

6.4 Status of Prior Mitigation Actions and Related Actions As the City of Rialto does not have a previously-approved LHMP, there are no prior mitigation actions for which the status may be reported. Capital improvement projects are long-term improvement and maintenance programs designed to preserve the City’s physical systems and facilities. The programs have been broad, and have included land and building acquisitions, development of off-street parking, street and sidewalk rehabilitation, sewer reconstruction, information technology systems development, public lighting projects, affordable housing development, and park acquisition and renovations. Capital improvements enhance economic development by attracting new businesses and new customers, bringing increased vitality to the City. Capital projects may be funded from several sources, including operating capital, grants, joint agency endeavors, public/private partnerships, special district projects, and debt financing. Tax increases and special districts have historically been used to fund capital projects; however, legislation now places severe restrictions on cities abilities to raise revenues in these ways. Special taxes must be approved by a two-thirds vote of the electorate; general taxes must be approved by a majority vote of the electorate. 6.5 Actions Considered But Not Included Hazard Vulnerability Goal Action Description Why Not Included? Terrorism Population Goal 2: Reduce Hazards Impact
School and Professional Mental Health Programs and Early Identification Establish and promote mental health and anti-bullying programs in schools and elsewhere to reduce chance of event by individuals suffering from mental illness.

More appropriate to school funding and management.

All Hazards Population Goal 4: Public Understanding Hazard Mitigation & Climate Adaptation School Clubs Can include activities such as developing hazard and capacity maps of school grounds or neighborhoods.

More appropriate to school funding and management.

All Hazards Population Goal 4: Public Understanding Outreach to Local Schools Work with local schools to create age-appropriate preparedness classes. More appropriate to school funding and management.

136
2023 LOCAL HAZARD MITIGATION PLAN
Wildfire Population Goal 4: Public Understanding Fire Safety Education Programs Develop new and expand existing public fire safety education programs. More appropriate to partner fire department.

Infectious Disease Population Goal 2: Reduce Hazards Impact Public Education Programs Conduct public education programs on communicable disease and methods to reduce spread At present, pandemic has died down enough to make this more appropriate to a future date.

All Hazards Critical Infrastructure Goal 1: Emergency Response Alternate Emergency Operations Center Infrastructure and Procedures Develop alternate EOC infrastructure and capability and conduct drills Budget/capacity issues.

The Planning Team considered a range of actions, and the City has chosen to put forward an extremely comprehensive and broad-based mitigation strategy that focuses on infrastructure but does not neglect the human needs of the City. The City’s view of resilience is that it cannot focus solely on the built environment or physical infrastructure. Human systems are as important to hazard mitigation, especially in light of increasing extreme weather events and other threats. During the course of mitigation action development, several actions were identified that, while worthy of implementation, were felt more appropriate to other funding sources or governmental entities. These actions are listed above. 6.6 Mitigation Implementation After mitigation projects have been selected for implementation, City staff conduct cost/benefit analyses to prioritize them. The following characteristics are considered when prioritizing mitigation projects: Hazard Mitigation Plan Goals addressed, political or community support, cost, hazards mitigated, effect on overall risk to life and property, ease of implementation, and limitations. As previously stated, although City Staff make recommendations to the Rialto City Council regarding prioritization and funding of future projects, the decision lies ultimately with the Councilmembers to fund and implement each mitigation project, because City Council approves the two year budget. The public has the opportunity to speak about planned

137
2023 LOCAL HAZARD MITIGATION PLAN
mitigation projects during public hearings, the budget approval process, or City Council meetings. Evaluating the proposed projects is done by each responsible department by surveying City staff assigned and members of the public, reviewing citizen complaints and public safety records, and conducting a cost analysis. In leaner budget years, some projects may lack funding, but staff will continue to identify potential funding streams as well as to set priorities based on a needs assessment in addition to the costs and benefits. Capital Improvement Projects As discussed earlier, capital projects are long-term improvement and maintenance programs designed to preserve the City’s physical systems and facilities. Most of Rialto’s capital improvement projects also address mitigation issues. The following information is provided as a supplement to the official mitigation projects above. Capital Improvement Projects are rated according to the following priority levels: • Priority 1: The project is urgent and/or mandated and must be completed quickly. Failure to address the project will impact the health, safety, or welfare of the community, or have a significant impact on the financial well-being of the City. The project must be initiated, or financial/opportunity losses will result. • Priority 2: The project is important and addressing it is necessary. The project impacts safety, law enforcement, health, welfare, economic base, and/or the quality of life in the community. • Priority 3: The project would enhance the quality of life and would provide a benefit to the community. Completion of the project would improve the community providing cultural, recreational, and/or aesthetic effects. • Priority 4: The project would be an improvement to the community but need not be completed within a five-year capital improvement program. The ability of the City to raise revenues is limited; programs and projects compete for resources, so it is important to have a clear understanding of the City’s capital needs, and imperative to strive to maintain a reasonable capital funding level which ensures the preservation of facilities and infrastructure. The cost/benefit analysis of these projects is conducted by the City’s finance department which reviews prior insurance claims, estimates of planned work and staff time, and the predicted financial benefit of completed projects. Other mitigation projects are rated in a similar manner to the City’s capital improvement projects. Future mitigation projects are dependent on the following factors: availability of

138
2023 LOCAL HAZARD MITIGATION PLAN
funding; availability of personnel; consistency with the capital improvement project schedule; and the project’s ability to mitigate an immediate hazard. Existing mitigation and capital improvement projects are possible due to identified funding and personnel to appropriately manage each project. The mitigation projects listed in the previous charts have been funded by various resources, including federal funding, state funding, county funding, and local taxes. Existing mitigation projects are dependent on the following factors: availability of funding; availability of personnel; consistency with the capital improvement project schedule; and the project’s ability to mitigate an immediate hazard. The list of mitigation actions discussed in this section is meant to be as comprehensive as possible, not only to guide City actions and priorities but to enable the City to apply for FEMA funding to carry out the broadest possible array of strategies to mitigate hazards and build resilience for the City. It is, of course, the City’s prerogative to determine its own priorities and processes. But from a hazard mitigation planning perspective, there are several strategic options that are worthy of consideration. • Municipal codes and zoning are powerful tools to drive mitigation actions by the public and by business. These regulations determine the urban form of a city, and by adding elements to require conformance to mitigation and resilience best practices, much good hazard mitigation work can be accomplished. This should be a high priority. • In terms of infrastructure, piggybacking mitigation actions through other infrastructure such as road repair and upgrades can be highly effective as well. Pavement covers a not-negligible percentage of any community and can be modified and enhanced to deliver a variety of benefits. • Along those lines, actions that can deliver tangible climate adaptation benefits should be prioritized as well. Climate impacts are accelerating to the point that extreme weather is visible to most people. During the development of this plan, many of the interviewees throughout various City departments reported that the weather was different in one way or another from even a few years ago, and that it was beginning to have impacts on day-to-day operations. One textbook describes climate adaptation as “hazard mitigation ten years in the future”. That view is a useful one to drive action. • Finally, hazard mitigation can be expensive. A variety of funding sources, both public and private, should be pursued, and the City should take advantage of favorable financial conditions when available to fund efforts. Insurance is becoming an issue across California, and the City should proactively begin looking

139
2023 LOCAL HAZARD MITIGATION PLAN
into new and innovative models of insurance to protect its citizens before the insurance companies, wary of the growing cost of climate-fueled events, forces it to act.

140
2023 LOCAL HAZARD MITIGATION PLAN
Section 7 – Planning Process Element A Requirements A1. Does the plan document the planning process, including how it was prepared and who was involved in the process for each jurisdiction? (Requirement 44 CFR § 201.6(c)(1)) A2. Does the plan document an opportunity for neighboring communities, local and regional agencies involved in hazard mitigation activities, and agencies that have the authority to regulate development, as well as businesses, academia, and other private and non-profit interests to be involved in the planning process? (Requirement 44 CFR § 201.6(b)(2)) A3. Does the plan document how the public was involved in the planning process during the drafting stage and prior to plan approval? (Requirement 44 CFR § 201.6(b)(1)) A4. Does the plan describe the review and incorporation of existing plans, studies, reports, and technical information? (Requirement 44 CFR § 201.6(b)(3)) 7.1 – Planning Process This LHMP (Local Hazard Mitigation Plan) is designed to meet the requirements of the Disaster Mitigation Act of 2000 (DMA 2000) and to ensure that the City is eligible for all appropriate benefits under state and federal law and practices. The LHMP planning process considers natural and human-caused hazards facing the City, making sure that all federal and state requirements are met and supporting HMP review. The LHMP planning team gathered information from a variety of sources, including participating municipal and county agencies, local organizations and utilities, federal and state agencies, and residents of the City. They solicited information from individuals with specific knowledge of natural hazards, historical events, planning and zoning codes, and recent planning decisions affecting hazard mitigation. The natural hazard mitigation strategies were FEMA’s Local Mitigation Planning Handbook, last updated in May 2023.

141
2023 LOCAL HAZARD MITIGATION PLAN
developed through an extensive planning process involving City agencies/officials and City residents. The planning area consists of the entire area within Rialto city limits.. The risk assessment for this hazard mitigation plan was performed for the entire planning area. The City of Rialto’s Fire Department was the primary agency driving creation of the Plan. The multi-disciplinary Planning Team consisted of: City of Rialto Brian Park, Fire Chief Tim Sullivan, Director of Maintenance and Facilities Cynthia Alvarado, Director of Parks, Recreation and Community Services Alberto Paiva, Director of Engineering Services Colby Cataldi, Director of Community Development Siri Champion, Senior Planner Jacob Green and Associates Patrick Marchman, AICP, SCR, Project Manager Tony Coletta, Senior Advisor All members with the exception of Jacob Green and Associates were affiliated with the City of Rialto. Team members were in close contact throughout the process, with several dedicated meetings in addition to bi-weekly standing meetings to ensure continued coordination taking place. A Hazard Vulnerability Assessment meeting to create a relative ranking of the City’s hazards occurred on April 6, 2023. The meeting was held virtually, with attendance from the Planning Team and throughout Rialto city government, with heavy fire and police attendance. The Planning Team invited staff from other City departments as well as stakeholders in neighboring cities to participate in updating the Hazard Mitigation Plan via email and through a series of meetings. These City departments included: • Community Compliance • Community Development • Parks, Recreation & Community Services • Engineering Services

142
2023 LOCAL HAZARD MITIGATION PLAN
• Finance • Fire • Human Resources & Risk Management • Maintenance & Facilities • Police The Planning Team incorporated information gained from this outreach throughout the preparation of the Hazard Mitigation Plan. Hazard mitigation planning must include review and incorporation of existing plans, studies, reports and technical information (44 CFR Section 201.6.b(3)). Information from the following plans, studies, reports, and technical information is incorporated as appropriate into the mitigation plan. The Planning Team reviewed several existing City and regional documents and policies to gather Information for the plan. Plan / Documents Description City of Rialto Municipal Code The City's Municipal Code was reviewed for information relating to capabilities assessments and potential mitigation actions City Critical Facilities List This was the basis for the critical facilities list included in the LHMP California State Hazard Mitigation Plan The State Hazard Mitigation Plan was reviewed for recent updates on state-wide hazard events and hazard information. San Bernardino County Hazard Mitigation Plan The San Bernardino County Hazard Mitigation Plan was reviewed for planning consistency and augmented event history for hazards that extend beyond Rialto city limits, such as drought and severe weather.

City of Rialto General Plan and Specific Plans
General Plan information was referred to in developing the overall community profile. Vulnerabilities identified in Specific Plan Areas were included as part of the vulnerability and risk assessment for wildfire, landslide, and flood. The General Plan and Specific Plans were included as part of the capability inventory for the City’s capability assessment. Emergency Operations Plan The Emergency Operations Plan (EOP) was reviewed for information related to response to the assessed natural hazards.

143
2023 LOCAL HAZARD MITIGATION PLAN
Other external resources utilized included maps and historical documents, as well as other city and county hazard mitigation plans. The information gathered from these documents was incorporated into the introduction, the risk assessment, and the mitigation strategies sections of this plan. 7.2 – Plan Update At the time of preparation, the City of Rialto did not have an active Hazard Mitigation Plan, although efforts had been made in the past to develop one. The City of Rialto’s first Disaster Committee was formed in the 1990s to create a Standardized Emergency Management System (SEMS) Multi-hazard Functional Plan for the Office of Emergency Services. This report acted to identify and properly handle emergencies in a timely and organized manor. Years later, SEMS was modified to support a Local Hazard Mitigation Plan which was developed by a committee consisting of members from the Rialto Fire and Rescue, Police Department, Public Works, various Finance Staff, Development Services, and members of the Rialto Unified School District. Draft Local Hazard Mitigation Plans were prepared in 2005 and 2012, with the most recent plan dating from August 2013. This plan is not recorded as being approved by FEMA. Updates to the 2012 plan were made in 2020, but these updates were not officially incorporated into the 2012 plan, being left as document edits and comments. As such, the preparers of the plan leaned heavily on the 2012 plan and 2020 updates, but even more so on the City’s General Plan, the Climate Adaptation Plan (prepared in 2020) and on neighboring cities’ hazard mitigation plans. 7.3 – Stakeholder Involvement Coordination with other local, state and federal agencies involved in hazard mitigation in the region helped to ensure consistency with other ongoing efforts. 44 CFR requires that opportunities for involvement in the planning process be provided to neighboring communities, local and regional agencies involved in hazard mitigation, agencies with authority to regulate development, businesses, academia, and other interests (Section 201.6.b.2).

Element E: Plan Update Requirements E1. Was the plan revised to reflect changes in development? (Requirement 44 CFR § 201.6(d)(3)) E2. Was the plan revised to reflect changes in priorities and progress in local mitigation efforts? (Requirement 44 CFR § 201.6(d)(3))

144
2023 LOCAL HAZARD MITIGATION PLAN
Stakeholders were invited to participate in development of the Plan at multiple stages in the plan development process. This outreach took place outside of the regular Planning Team meeting schedule, and outreach results were discussed during regular meetings. • Local and regional agencies involved in hazard mitigation activities o City of Rialto Engineering Services o City of Rialto Fire o City of Rialto Maintenance & Facilities o City of Rialto Police o San Bernardino County Flood Control District • Agencies that have the authority to regulate development o City of Rialto Community Compliance o City of Rialto Community Development • Neighboring communities o Neighboring local governments were contacted at several stages during the process, and copies of the initial draft LHMP were sent for review and comment to the cities of: § Colton § Bloomington § Fontana § San Bernardino • Representatives of businesses, academia, and other private organizations o Outreach took place by phone and by email to entities with both relevant knowledge and major local employers including § Southern California Edison § Rialto Water Services § Rialto Unified School District • Representatives of nonprofit organizations, including community-based organizations, that work directly with and/or provide support to underserved communities and socially vulnerable populations, among others o Attempts to solicit involvement and comment were made from the following organizations: § City of Rialto Homeless Assistance § San Bernardino County Homeless Partnership Upon completion of the initial draft, full copies of the Plan were sent for review and

145
2023 LOCAL HAZARD MITIGATION PLAN
comment directly to planning leadership and staff of these bodies, including: • San Bernardino County • San Bernardino County Flood Control District • Southern California Association of Governments • Cities of: o Colton o Bloomington o Fontana o San Bernardino 7.4 – Public Involvement Public outreach for input on the Plan took place in several ways. • The public was informed via several media of both an online survey and a public in-person meeting. Notices were run in the Rialto Record (in English) as well as on the Rialto Channel, the city’s in-house television channel, the City’s website, and the City’s Facebook page (in English and Spanish). These notices included links to the online survey and information about the upcoming in-person meeting. • An online survey was created in English and Spanish to gauge citizen awareness and concern regarding the list of hazards established through the City’s internal Hazards Assessment Workshop on April 3, 2023. • On April 27, 2023, a public meeting was held. The meeting included an initial presentation and printed surveys in English and Spanish for attendees to fill out. After the meeting, City staff distributed copies of the survey internally for City employees to fill out. A total of 47 surveys were completed both online and in person. Survey results summaries are included in the Appendices to the Plan. Public feedback was considered throughout Plan development and influenced the final Plan, most notably in determination of appropriate mitigation actions for the City as well as perception of wildfire risk in northern neighborhoods of Rialto and the extent of the local unhoused population. Copies of the Plan will be catalogued and made available at City Hall and West Hollywood Public Library. The existence and location of these copies will be publicized on City websites and social media. A copy of the Plan and any proposed changes will be posted on the City’s website. The website will also include an email address and phone number to which people can direct their comments, recommendations, and concerns.

146
2023 LOCAL HAZARD MITIGATION PLAN
The Hazard Mitigation Coordinator will work with stakeholders within City government to provide opportunities for the public to be involved throughout the five-year cycle, not just during the actual plan development phase. Opportunities may include piggybacking off existing public outreach meetings held by police or fire departments, booths at farmer’s markets or other public events in the City, and periodic updates to City Council in public meetings. Specific events that will be promoted as part of hazard mitigation planning public involvement will include: • The Great California Shakeout • National Fire Protection Association Fire Week • City of Rialto Police Department neighborhood meetings 7.5 – Plan Incorporation The effectiveness of the Plan depends on successful implementation of the mitigation actions. This includes integrating mitigation actions into existing city plans, policies, programs, and other implementation mechanisms. The key city plans that should reference or incorporate content from this LHMP include: Ÿ Rialto General Plan Safety Element should incorporate relevant mitigation mapping and analysis ensure the goals and policies of this plan are reinforced throughout future developments and projects proposed within the City. The Safety Element is currently being updated, and staff working on the Safety Element met repeatedly with staff preparing the LHMP to coordinate efforts in a variety of ways, including overlap and incorporation of policies and mitigation actions. Ÿ Rialto Emergency Operations Plan (EOP), which focuses on the effective preparedness and response to hazard events that occur within the city. Incorporation of relevant content from this plan into the EOP ensures consistency regarding the hazards addressed in both plans. Ÿ Rialto Capital Improvement Plan (CIP) identifies key infrastructure investments throughout the city that may include hazard mitigation elements. Incorporation of mitigation planning elements into the CIP may assist with enhancing infrastructure investment through additional funding and/or modification of improvements to include hazard mitigation elements. Mitigation strategies are regularly reviewed through the City's existing programs, including the City General Plan review and updates, Building and Safety municipal code review and

147
2023 LOCAL HAZARD MITIGATION PLAN
updates, transportation and public works projects, commercial and residential code compliance, housing authority programs, capital improvement plans and projects, and City Emergency Plan review and updates. Hazard identification and risk assessment is part of the development approval process. The chart of mitigation strategies will be reviewed at regular intervals to identify funding and to incorporate work into other City projects when possible. Commercial and Residential Code Compliance, with assistance from the Planning and Building and Safety Divisions, will look for ways to strengthen the Municipal Code and other laws to support the City’s mitigation strategies. In addition, there are several public meetings which will be used to encourage both public and private input and to adopt or incorporate mitigation projects into community outreach. 7.6 – Plan Maintenance Element D: Plan Maintenance Requirements D1. Is there discussion of how each community will continue public participation in the plan maintenance process? (Requirement 44 CFR § 201.6(c)(4)(iii)) D2. Is there a description of the method and schedule for keeping the plan current (monitoring, evaluating, and updating the mitigation plan within a five-year cycle)? (Requirement 44 CFR § 201.6(c)(4)(i)) D3. Does the plan describe a process by which each community will integrate the requirements of the mitigation plan into other planning mechanisms, such as comprehensive or capital improvement plans, when appropriate? (Requirement 44 CFR § 201.6(c)(4)(ii)) Monitoring, Evaluating and Updating the Plan The Hazard Mitigation Plan will be monitored by a designated City staff member, the Hazard Mitigation Coordinator. This staff member will make a record of necessary revisions to ensure that the most accurate and up to date information is included in the Plan. The Emergency Management Coordinator will also review the mitigation actions yearly and revise the plan based on progress towards the outlined mitigation actions or new mitigation actions that were identified for existing hazards. The Coordinator will also reach out to relevant City departments to integrate their tracking updates for those actions that overlap with the LHMP. The Hazard Mitigation Coordinator will evaluate the Plan and make recommendations for future updates and enhancements. This review will be completed annually.

148
2023 LOCAL HAZARD MITIGATION PLAN
Each mitigation action will be reviewed to determine its continued relevance to changing situations and land developments in the City, as well as changes in State or Federal policy, and to ensure that each action is addressing current and expected conditions. The risk assessment portion of the Plan will also be reviewed to determine if this information should be updated or modified. Factors to be reported on will include: • Any changes in the nature or magnitude of risks identified in the Plan. • The status of these actions, and, where applicable, will report on which actions worked well. • Whether difficulties have been encountered, and if so, what they are. • How coordination efforts have been proceeding, and which actions should be revised. After this initial review, the Hazard Mitigation Coordinator will reach out to stakeholders such as neighborhood groups, fire and law enforcement agencies, community groups, social service agencies, transportation, planning and public works staff to discuss progress towards mitigation objectives and potential plan revisions. Specific positions that need to be involved include: • Fire Chief • Police Chief • Community Development Manager The Hazard Mitigation Coordinator will also lead efforts to secure adequate funding for the mitigation activities. After the City’s budget is passed by City Council, the Hazard Mitigation Coordinator will collaborate with stakeholders to apply for hazard mitigation grants that will help the City implement the mitigation activities that are not included in the City’s two year budget. Starting at year four after Plan approval, the Hazard Mitigation Coordinator will begin the process to formally update the Hazard Mitigation Plan. Depending on City preference, the Plan update will be conducted by Public Safety in cooperation with Community Development, or alternately may be conducted by a contracted firm. In either case, the Hazard Mitigation Coordinator will be responsible for driving the update process forward. When the Plan update is complete, copies of the new Plan update as well as all previous plans will be catalogued and kept in appropriate departments and public locations. Incorporation into Existing Planning Mechanisms Mitigation actions identified in this Plan will be socialized through City departments and through the City's existing programs, including the City General Plan review and updates,

149
2023 LOCAL HAZARD MITIGATION PLAN
Building and Safety municipal code review and updates, transportation and public works projects, commercial and residential code compliance, housing authority programs, capital improvement plans and projects, and City Emergency Plan review and updates. The chart of mitigation strategies will be reviewed by the Hazard Mitigation Coordinator annually at a minimum to identify funding and to incorporate work into other City projects when possible. For example, the Hazard Mitigation Planning team will work together during the City’s budget process, capital improvement project planning, and other areas as appropriate to incorporate mitigation projects.

Continued Public Participation in the Plan Maintenance Process Copies of the Plan will be catalogued and made available at City Hall and Rialto Public Library. The existence and location of these copies will be publicized on City websites and social media. A copy of the Plan and any proposed changes will be posted on the city website. The website will also include an email address and phone number to which people can direct their comments, recommendations, and concerns. If changes are required of the plan by CalOES or FEMA, the City’s Hazard Mitigation Coordinator will notify the public and encourage their participation in meetings to provide input and review any changes. The Coordinator may also send notifications to the public on plan amendments, completion of mitigation actions, and notification of programs available for mitigation. The Hazard Mitigation Coordinator will work with stakeholders within City government to provide opportunities for the public to be involved throughout the five-year cycle, not just during the actual plan development phase. Opportunities may include piggybacking off existing public outreach meetings held by police or fire departments, booths at farmer’s markets or other public events in the City, and periodic updates to City Council in public meetings. Specific events that will be promoted as part of hazard mitigation planning public involvement will include: • The Great California Shakeout • National Fire Prevention Week • City of Rialto Police Area Command Meeting 7.7 – Plan Adoption

150
2023 LOCAL HAZARD MITIGATION PLAN
Element F: Plan Adoption F1. For single-jurisdictional plans, has the governing body of the jurisdiction formally adopted the plan to be eligible for certain FEMA assistance? (Requirement 44 CFR § 201.6(c)(5)) F2. For multi-jurisdictional plans, has the governing body of each jurisdiction officially adopted the plan to be eligible for certain FEMA assistance? (Requirement 44 CFR § 201.6(c)(5)) Primary Point of Contact The Point of Contact for information regarding this plan is: Christopher Jensen Division Chief/Fire Marshal Rialto Fire Department 131 S. Willow Rialto, CA 92376 (909) 820-2504 (Office) [email protected] General Inquiries regarding the Hazard Mitigation Plan can be sent to: City of Rialto 150 S Palm, Rialto, CA 92376 909-820-2525

151
Appendices Appendix A: Sample Adoption Resolution Note to Reviewers: When this plan has been reviewed and approved pending adoption by FEMA Region IX, the adoption resolutions will be signed added to this appendix. Sample Resolution: City of Rialto Resolution # ______ Adopting the City of Rialto Hazard Mitigation Plan WHEREAS, The City of Rialto recognizes the threat that natural and manmade hazards pose to people and property within our community; and WHEREAS, undertaking hazard mitigation actions will reduce the potential for harm to people and property from future hazard occurrences; and WHEREAS, the U.S. Congress passed the Disaster Mitigation Act of 2000 (“Disaster Mitigation Act”) emphasizing the need for pre-disaster mitigation of potential hazards; and WHEREAS, the Disaster Mitigation Act made available hazard mitigation grants to state and local governments; and WHEREAS, an adopted Local Hazard Mitigation Plan is required as a condition of future funding for mitigation projects under multiple FEMA pre- and post-disaster mitigation grant programs; and WHEREAS, the City of Rialto fully participated in the FEMA-prescribed mitigation planning process to prepare this local hazard mitigation plan; and WHEREAS, the California Office of Emergency Services and Federal Emergency Management Agency, Region IX officials have reviewed the City of Rialto Local Hazard Mitigation Plan and approve it contingent upon this official adoption of the participating governing body; and WHEREAS, the City of Rialto desires to comply with the requirements of the Disaster Mitigation Act and to augment its emergency planning efforts by formally adopting the City of Rialto Hazard Mitigation Plan by reference into the Safety Element of the General Plan in accordance with the requirements of AB 2140; and

152
2023 LOCAL HAZARD MITIGATION PLAN
WHEREAS, adoption by the governing body for the City of Rialto demonstrates the jurisdiction’s commitment to fulfilling the mitigation goals and objectives outlined in this Local Hazard Mitigation Plan; and WHEREAS, adoption of this legitimizes the plan and authorizes responsible agencies to carry out their responsibilities under the plan. NOW, THEREFORE, BE IT RESOLVED that the City of Rialto adopts the City of Rialto Local Hazard Mitigation Plan as an official plan; and BE IT RESOLVED, that the City of Rialto adopts the Rialto Local Hazard Mitigation Plan by reference into the safety element of their general plan in accordance with the requirements of AB 2140; and BE IT FURTHER RESOLVED, the City of Rialto will submit this adoption resolution to the California Office of Emergency Services and FEMA Region IX officials to enable the plan’s final approval in accordance with the requirements of the Disaster Mitigation Act of 2000 and to establish conformance with the requirement of AB 2140. Passed: (date) Certifying Official Appendix B: LHMP Approval Process

153

154
2023 LOCAL HAZARD MITIGATION PLAN
Appendix C: Relevant Municipal Code Sections Chapter 18.74 - ALQUIST-PRIOLO ACT SPECIAL STUDIES ZONE Sections:

18.74.010 - Scope. The ordinance codified in this chapter is adopted pursuant to the requirements of the Alquist-Priolo Special Studies Zones Act (Public Resources Code, Section 2621, et seq.) and the adopted policies and criteria of the State Mining and Geology Board. Within the special studies zones shown on the maps prepared by the State Geologist pursuant to the act, all applicants for a permit for a project shall comply with all of the provisions of the act, the adopted policies and criteria and this chapter. The maps delineating the special studies zones are on file in the office of the director of development services and the chief building official. (Ord. 1234 (part), 1995: Ord. 702 § 1 (part), 1976) 18.74.020 - Definitions. As used in this chapter, the following terms have the following meanings: A. "Project" means: 1. Any new real estate development which contemplates the eventual construction of structures for human occupancy, subject to the Subdivision Map Act. 2. Any new real estate development for which a tentative tract map has not yet been approved. 3. Any structure for human occupancy, other than a single-family wood-frame dwelling not exceeding two stories. For the purpose of this chapter, a mobile home whose body width exceeds eight feet shall be considered a single-family wood-frame dwelling not exceeding two stories. 4. Any single-family wood-frame dwelling which is built or located as part of a development of four or more such dwellings constructed by a single

155
person, individual partnership, corporation, or other organization. No geologic report shall be required with respect to such single-family wood-frame dwelling if the dwelling is located within a new real estate development, as described in paragraph 1 or 2 of this subsection for which development a geologic report has been either approved or waived pursuant to this chapter. B. "Project" does not include: 1. The conversion of an existing apartment complex into a condominium; 2. Alterations or additions to any structure for human occupancy within a special studies zone, the value of which does not exceed fifty percent of the value of the structure. C. "Structure for human occupancy" means a structure that is regularly, habitually or primarily occupied by humans, including but not limited to the following: all residences, whether single-family or multiple that are not exempted by the act; retail stores; theaters; manufacturing building; public service structures, such as civic centers, hospitals, and schools, clubhouses, churches and recreation buildings, but not including freeways, roadways, bridges, railways, airport runways and tunnels. D. "Permit" means: 1. Conditional development permit. 2. Public use permit. 3. Plot plan, development plan or certificate of occupancy approval. 4. Specific plan of land use. 5. Building permit. 6. Tentative subdivision map; 7. Tentative parcel map. (Ord. 702 § 1 (part), 1976) 18.74.030 - Application requirements. A. All applications for a permit for a real estate development or for a structure for human occupancy that lies within a special studies zone shown on the maps prepared by the State Geologist pursuant to the Alquist-Priolo Special Studies Zones Act shall be accompanied by a geologist's report. B. The report shall be issued by a geologist who is registered in the state, shall define, and delineate any hazard of surface fault rupture, and shall be prepared in accordance with the requirements of the act. C. A geologic report may be waived if the geologist employed or retained by the city determines that no undue hazard from surface fault rupture exists and the waiver is approved by the State Geologist.

156
2023 LOCAL HAZARD MITIGATION PLAN
D. After a geologic report has been approved or waived for a project, further geologic reports shall not be required for subsequent phases of the project, including building permits, unless new geologic data is recorded that warrants further investigation of the site. (Ord. 702 § 1 (part), 1976) 18.74.040 - Geologic report—Notice to applicant of findings. Within thirty days from the date of filing of geologic report or waiver thereof, the planning division shall notify the applicant of the findings made by the geologist employed or retained by the city. When further information is requested and a revised report is submitted, a new thirty-day period for review and action will commence. (Ord. 1234 (part), 1995: Ord. 1169 § 1 (part), 1992: Ord. 702 § 1 (part), 1976) 18.74.050 - Processing fee. Upon the filing of a geologic report with the planning division as set forth by the provisions of this chapter, an application fee in the amount prescribed by resolution of the city council shall be paid to the city to defray the cost for the processing and review of the geologic report. (Ord. 1234 (part), 1995: Ord. 1169 § 1 (part), 1992: Ord. 702 § 1 (part), 1976) 18.74.060 - Permit not to allow violation of certain regulations. Within every special studies zone delineated on the maps issued by the State Geologist, no permit or approval shall be granted for any project if the permit or approval would allow or require a structure used for human occupancy to be constructed or placed in violation of the requirements of the act or the policies and criteria of the State Mining and Geology Board adopted pursuant to the act. (Ord. 702 § 1 (part), 1976) 18.74.070 - Geologic report—Completion or waiver required. No application for a permit shall be considered as complete for filing and the time limitations for processing a permit shall not begin to run until the geologic report required by the act has been accepted as complete or until a waiver thereof has been finally approved. (Ord. 702 § 1 (part), 1976)

157
Chapter 18.75 - FLOODPLAIN MANAGEMENT ORDINANCE Sections:

Footnotes: --- (8) --- Prior Ordinance History: 1173

18.75.010 - Statutory authorization. The Legislature of the State of California has, in Government Code Section 37100, authorized the legislative bodies of cities to pass ordinances not in conflict with the Constitution and laws of the State of California or the United States. The City Council of the City of Rialto does hereby adopt the following floodplain management regulations in order to comply with the National Flood Insurance Program and to assist its citizenry in obtaining flood insurance at cheaper rates and in greater amounts. (Ord. 1318 § 1, 2001) 18.75.020 - Findings of fact. A. The flood hazard areas of the City of Rialto are subject to periodic inundation which results in loss of life and property, health and safety hazards, disruption of commerce and governmental services, extraordinary public expenditures for flood protection and relief, and impairment of the tax base, all of which adversely affect the public health, safety, and general welfare. B. These flood losses are caused by uses that are inadequately elevated, flood proofed, or protected from flood damage. The cumulative effect of obstructions in areas of special flood hazards that increase flood heights and velocities also contribute to the flood loss. (Ord. 1318 § 1, 2001) 18.75.030 - Statement of purpose. It is the purpose of this chapter to promote the public health, safety, and general welfare, and to minimize public and private losses due to flood conditions in specific areas by provisions designed to: A. Protect human life and health.

158
2023 LOCAL HAZARD MITIGATION PLAN
B. Minimize expenditure of public money for costly flood control projects. C. Minimize the need for rescue and relief efforts associated with flooding and generally undertaken at the expense of the general public. D. Minimize prolonged business interruptions. E. Minimize damage to public facilities and utilities such as water and gas mains; electric, telephone and sewer lines; and streets and bridges located in areas of special flood hazard. F. Help maintain a stable tax base by providing for the sound use and development of areas of special flood hazard so as to minimize future blighted areas caused by flood damage. G. Ensure that potential buyers are notified that property is in an area of special flood hazard; and H. Ensure that those who occupy the areas of special flood hazard assume responsibility for their actions. (Ord. 1318 § 1, 2001) 18.75.040 - Methods of reducing flood losses. In order to accomplish its purposes, this chapter includes methods and provisions to: A. Restrict or prohibit uses which are dangerous to health, safety, and property due to water or erosion hazards, or which result in damaging increases in erosion or flood heights or velocities. B. Require that uses vulnerable to floods, including facilities which serve such uses, be protected against flood damage at the time of initial construction. C. Control the alteration of natural floodplains, stream channels, and natural protective barriers, which help accommodate or channel flood waters. D. Control filling, grading, dredging, and other development which may increase flood damage; and E. Prevent or regulate the construction of flood barriers which will unnaturally divert flood waters, or which may increase flood hazards in other areas. (Ord. 1318 § 1, 2001) 18.75.050 - Definitions. Unless specifically defined below, words or phrases used in this chapter shall be interpreted so as to give them the meaning they have in common usage and to give this chapter its most reasonable application.

159
"Accessory use" means a use that is incidental and subordinate to the principal use of the parcel of land on which it is located. "Alluvial fan" means a geomorphologic feature characterized by a cone or fan-shaped deposit of boulders, gravel, and fine sediments that have been eroded from mountain slopes, transported by flood flows, and then deposited on the valley floors, and which is subject to flash flooding, high velocity flows, debris flows, erosion, sediment movement and deposition, and channel migration. "Apex" means the point of highest elevation on an alluvial fan, which on undisturbed fans is generally the point where the major stream that formed the fan emerges from the mountain front. "Appeal" means a request for a review of the Floodplain Administrator's interpretation of any provision of this chapter. "Area of shallow flooding" means a designated AO or AH Zone on the Flood Insurance Rate Map (FIRM). The base flood depths range from one to three feet; a clearly defined channel does not exist; the path of flooding is unpredictable and indeterminate; and velocity flow may be evident. Such flooding is characterized by ponding or sheet flow. "Area of special flood hazard"—See "Special flood hazard area." "Area of special flood-related erosion hazard" is the land within a community that is most likely to be subject to severe flood-related erosion losses. The area may be designated as Zone E on the Flood Insurance Rate Map (FIRM). "Area of special mudslide (i.e., mudflow) hazard" is the area subject to severe mudslides (i.e., mudflows). The area is designated as Zone M on the Flood Insurance Rate Map (FIRM). "Base flood" means a flood which has a one percent chance of being equaled or exceeded in any given year (also called the "100-year flood"). Base flood is the term used throughout this chapter. "Basement" means any area of the building having its floor subgrade-i.e., below ground level-on all sides. "Building"—See "Structure". "Development" means any man-made change to improved or unimproved real estate, including but not limited to buildings or other structures, mining, dredging, filling, grading, paving, excavation or drilling operations or storage of equipment or materials.

160
2023 LOCAL HAZARD MITIGATION PLAN
"Encroachment" means the advance or infringement of uses, plant growth, fill, excavation, buildings, permanent structures, or development into a floodplain, which may impede or alter the flow capacity of a floodplain. "Existing manufactured home park or subdivision" means a manufactured home park or subdivision for which the construction of facilities for servicing the lots on which the manufactured homes are to be affixed (including, at a minimum, the installation of utilities, the construction of streets, and either final site grading or the pouring of concrete pads) is completed before the effective date of the floodplain management regulations adopted by a community. "Expansion to an existing manufactured home park or subdivision" means the preparation of additional sites by the construction of facilities for servicing the lots on which the manufactured homes are to be affixed (including the installation of utilities, the construction of streets, and either final site grading or the pouring of concrete pads). "Flood, flooding, or flood water" means: 1. A general and temporary condition of partial or complete inundation of normally dry land areas from the overflow of inland or tidal waters; the unusual and rapid accumulation or runoff of surface waters from any source; and/or mudslides (i.e., mudflows); and 2. The condition resulting from flood-related erosion. "Flood Boundary and Floodway Map (FBFM)" means the official map on which the Federal Emergency Management Agency or Federal Insurance Administration has delineated both the areas of special flood hazards and the floodway. "Flood Hazard Boundary Map" means the official map on which the Federal Emergency Management Agency or Federal Insurance Administration has delineated the areas of flood hazards. "Flood Insurance Rate Map (FIRM)" means the official map on which the Federal Emergency Management Agency or Federal Insurance Administration has delineated both the areas of special flood hazards and the risk premium zones applicable to the community. "Flood Insurance Study" means the official report provided by the Federal Insurance Administration that includes flood profiles, the Flood Insurance Rate Map, the Flood Boundary and Floodway Map, and the water surface elevation of the base flood. "Flood-related erosion" means the collapse or subsidence of land along the shore of a lake or other body of water as a result of undermining caused by waves or currents of water exceeding anticipated cyclical level or suddenly caused by an unusually high water level in a natural body of water, accompanied by a severe storm, or by an unanticipated

161
force of nature, such as a flash flood or an abnormal tidal surge, or by some similarly unusually and unforeseeable event which results in flooding. "Flood-related erosion area" or "Flood-related erosion prone area" means a land area adjoining the shore of a lake or other body of water, which due to the composition of the shoreline or bank and high water levels or wind-driven currents, is likely to suffer flood-related erosion damage. "Flood-related erosion area management" means the operation of an overall program of corrective and preventive measures for reducing flood-related erosion damage, including but not limited to emergency preparedness plans, flood-related erosion control works, and floodplain management regulations. "Floodplain or flood-prone area" means any land area susceptible to being inundated by water from any source—see "Flood, flooding, or flood water." "Floodplain Administrator" is the individual appointed to administer and enforce the floodplain management regulations. "Floodplain management" means the operation of an overall program of corrective and preventive measures for reducing flood damage and preserving and enhancing, where possible, natural resources in the floodplain, including but not limited to emergency preparedness plans, flood control works, floodplain management regulations, and open space plans. "Floodplain management regulations" means this chapter and other zoning chapters, subdivision regulations, building codes, health regulations, special purpose ordinances (such as grading and erosion control) and other application of police power which control development in flood-prone areas. This term describes federal, state or local regulations in any combination thereof that provide standards for preventing and reducing flood loss and damage. "Flood proofing" means any combination of structural and nonstructural additions, changes, or adjustments to structures which reduce or eliminate flood damage to real estate or improved real property, water and sanitary facilities, structures, and their contents. (Refer to FEMA Technical Bulletins TB 1-93, TB 3- 93, and TB 7-93 for guidelines on dry and wet flood proofing.) "Floodway" means the channel of a river or other watercourse and the adjacent land areas that must be reserved in order to discharge the base flood without cumulatively increasing the water surface elevation more than one foot. Also referred to as "Regulatory Floodway". "Floodway fringe" is that area of the floodplain on either side of the "Regulatory Floodway" where encroachment may be permitted.

162
2023 LOCAL HAZARD MITIGATION PLAN
"Fraud and victimization" as related to Section 18.75.270, Variance Procedure, of this chapter, means that the variance granted must not cause fraud on or victimization of the public. In examining this requirement, the City Council will consider the fact that every newly constructed building adds to government responsibilities and remains a part of the community for fifty to one-hundred years. Buildings that are permitted to be constructed below the base flood elevation are subject during all those years to increased risk of damage from floods, while future owners of the property and the community as a whole are subject to all the costs, inconvenience, danger, and suffering that those increased flood damages bring. In addition, future owners may purchase the property, unaware that it is subject to potential flood damage, and can be insured only at very high flood insurance rates. "Functionally dependent use" means a use that cannot perform its intended purpose unless it is located or carried out in close proximity to water. The term includes only docking facilities, port facilities that are necessary for the loading and unloading of cargo or passengers, and ship building and ship repair facilities, and does not include long-term storage or related manufacturing facilities. "Governing body" is the city council of the city. "Hardship" as related to Section 18.75.270, Variance Procedure, of this chapter means the exceptional hardship that would result from a failure to grant the requested variance. The city council requires that the variance be exceptional, unusual, and peculiar to the property involved. Mere economic or financial hardship alone is not exceptional. Inconvenience, aesthetic considerations, physical handicaps, personal preferences, or the disapproval of one's neighbors likewise cannot, as a rule, qualify as an exceptional hardship. All of these problems can be resolved through other means without granting a variance, even if the alternative is more expensive, or requires the property owner to build elsewhere or put the parcel to a different use than originally intended. "Highest adjacent grade" means the highest natural elevation of the ground surface prior to construction next to the proposed walls of a structure. "Historic structure" means any structure that is: 1. Listed individually in the National Register of Historic Places (a listing maintained by the Department of Interior) or preliminarily determined by the Secretary of the Interior as meeting the requirements for individual listing on the National Register. 2. Certified or preliminarily determined by the Secretary of the Interior as contributing to the historical significance of a registered historic district or a district preliminarily determined by the Secretary to qualify as a registered historic district.

163

3. Individually listed on a state inventory of historic places in states with historic preservation programs which have been approved by the Secretary of Interior; or 4. Individually listed on a local inventory of historic places in communities with historic preservation programs that have been certified either by an approved state program as determined by the Secretary of the Interior or directly by the Secretary of the Interior in states without approved programs. "Levee" means a man-made structure, usually an earthen embankment, designed and constructed in accordance with sound engineering practices to contain, control or divert the flow of water so as to provide protection from temporary flooding. "Levee system" means a flood protection system that consists of a levee, or levees, and associated structures, such as closure and drainage devices, which are constructed and operated in accord with sound engineering practices. "Lowest floor" means the lowest floor of the lowest enclosed area, including basement—(see "Basement" definition). 1. An unfinished or flood resistant enclosure below the lowest floor that is usable solely for parking of vehicles, building access or storage in an area other than a basement area, is not considered a building's lowest floor provided it conforms to applicable non-elevation design requirements, including, but not limited to: a. The wet flood proofing standard in Section 18.75.170. b. The anchoring standards in Section 18.75.170. c. The construction materials and methods standards in Section 18.75.170. d. The standards for utilities in Section 18.75.180. 2. For residential structures, all subgrade-enclosed areas are prohibited as they are considered to be basements (see "Basement" definition). This prohibition includes below-grade garages and storage areas. "Manufactured home" means a structure, transportable in one or more sections, which is built on a permanent chassis and is designed for use with or without a permanent foundation when attached to the required utilities. The term "manufactured home" does not include a "recreational vehicle". "Manufactured home park or subdivision" means a parcel (or contiguous parcels) of land divided into two or more manufactured home lots for rent or sale. "Market Value" shall be determined by estimating the cost to replace the structure in new condition and adjusting that cost figure by the amount of depreciation, which has accrued since the structure was constructed. The cost of replacement of the structure shall

164
2023 LOCAL HAZARD MITIGATION PLAN
be based on a square foot cost factor determined by reference to a building cost estimating guide recognized by the building construction industry. The amount of depreciation shall be determined by taking into account the age and physical deterioration of the structure and functional obsolescence as approved by the floodplain administrator but shall not include economic or other forms of external obsolescence. Use of replacement costs or accrued depreciation factors different from those contained in recognized building cost estimating guides may be considered only if such factors are included in a report prepared by an independent professional appraiser and supported by a written explanation of the differences. "Mean sea level" means, for purposes of the National Flood Insurance Program, the National Geodetic Vertical Datum (NGVD) of 1929 or other datum, to which base flood elevations shown on a community's Flood Insurance Rate Map are referenced. "Mudslide" describes a condition where there is a river, flow or inundation of liquid mud down a hillside, usually as a result of a dual condition of loss of brush cover and the subsequent accumulation of water on the ground, preceded by a period of unusually heavy or sustained rain. "Mudslide (i.e., mudflow) prone area" means an area with land surfaces and slopes of unconsolidated material where the history, geology, and climate indicate a potential for mudflow. "New construction," for floodplain management purposes, means structures for which the "start of construction" commenced on or after the effective date of floodplain management regulations adopted by this community, and includes any subsequent improvements to such structures. "New manufactured home park or subdivision" means a manufactured home park or subdivision for which the construction of facilities for servicing the lots on which the manufactured homes are to be affixed (including at a minimum, the installation of utilities, the construction of streets, and either final site grading or the pouring of concrete pads) is completed on or after the effective date of floodplain management regulations adopted by this community. "Obstruction" includes, but is not limited to, any dam, wall, wharf, embankment, levee, dike, pile, abutment, protection, excavation, channelization, bridge, conduit, culvert, building, wire, fence, rock, gravel, refuse, fill, structure, vegetation or other material in, along, across or projecting into any watercourse which may alter, impede, retard or change the direction and/or velocity of the flow of water, or due to its location, its propensity to snare or collect debris carried by the flow of water, or its likelihood of being carried downstream. "One-hundred-year flood" or "100-year flood"—See "Base flood."

165
"Public safety and nuisance" as related to Section 18.75.270, Variance Procedure, of this chapter means that the granting of a variance must not result in anything which is injurious to safety or health of an entire community or neighborhood, or any considerable number of persons, or unlawfully obstructs the free passage or use, in the customary manner, of any navigable lake, or river, bay, stream, canal, or basin. "Recreational vehicle" means a vehicle that is: 1. Built on a single chassis. 2. 400 square feet or less when measured at the largest horizontal projection. 3. Designed to be self-propelled or permanently towable by a light-duty truck; and 4. Designed primarily not for use as a permanent dwelling but as temporary living quarters for recreational, camping, travel, or seasonal use. "Regulatory floodway" means the channel of a river or other watercourse and the adjacent land areas that must be reserved in order to discharge the base flood without cumulatively increasing the water surface elevation more than one foot. "Remedy a violation" means to bring the structure or other development into compliance with State or local floodplain management regulations, or, if this is not possible, to reduce the impacts of its noncompliance. Ways that impacts may be reduced include protecting the structure or other affected development from flood damages, implementing the enforcement provisions of the chapter or otherwise deterring future similar violations, or reducing State or Federal financial exposure with regard to the structure or other development. "Riverine" means relating to, formed by, or resembling a river (including tributaries), stream, brook, etc. "Sheet flow area"—See "Area of shallow flooding". "Special flood hazard area (SFHA)" means an area in the floodplain subject to a 1 percent or greater chance of flooding in any given year. It is shown on an FHBM or FIRM as Zone A, AO, Al-A30, AE, A99, or AH. "Start of construction" includes substantial improvement and other proposed new development and means the date the building permit was issued, provided the actual start of construction, repair, reconstruction, rehabilitation, addition, placement, or other improvement was within 180 days from the date of the permit. The actual start means either the first placement of permanent construction of a structure on a site, such as the pouring of slab or footings, the installation of piles, the construction of columns, or any work beyond the stage of excavation; or the placement of a manufactured home on a

166
2023 LOCAL HAZARD MITIGATION PLAN
foundation. Permanent construction does not include land preparation, such as clearing, grading, and filling; nor does it include the installation of streets and/or walkways; nor does it include excavation for a basement, footings, piers, or foundations or the erection of temporary forms; nor does it include the installation on the property of accessory buildings, such as garages or sheds not occupied as dwelling units or not part of the main structure. For a substantial improvement, the actual start of construction means the first alteration of any wall, ceiling, floor, or other structural part of a building, whether or not that alteration affects the external dimensions of the building. "Structure" means a walled and roofed building that is principally above ground; this includes a gas or liquid storage tank or a manufactured home. "Substantial damage" means damage of any origin sustained by a structure whereby the cost of restoring the structure to its before damaged condition would equal or exceed fifty percent of the market value of the structure before the damage occurred. "Substantial improvement" means any reconstruction, rehabilitation, addition, or other proposed new development of a structure, the cost of which equals or exceeds fifty percent of the market value of the structure before the "start of construction" of the improvement. This term includes structures that have incurred "substantial damage", regardless of the actual repair work performed. The term does not, however, include either: 1. Any project for improvement of a structure to correct existing violations or state or local health, sanitary, or safety code specifications which have been identified by the local code enforcement official and which are the minimum necessary to assure safe living conditions, or 2. Any alteration of a "historic structure", provided that the alteration will not preclude the structure's continued designation as a "historic structure". "Variance" means a grant of relief from the requirements of this chapter, which permits construction in a manner that would otherwise be prohibited by this chapter. "Violation" means the failure of a structure or other development to be fully compliant with this chapter. A structure or other development without the elevation certificate, other certifications, or other evidence of compliance required in this chapter is presumed to be in violation until such time as that documentation is provided. "Water surface elevation" means the height, in relation to the National Geodetic Vertical Datum (NGVD) of 1929, (or other datum, where specified) of floods of various magnitudes and frequencies in the floodplains of coastal or riverine areas. "Watercourse" means a lake, river, creek, stream, wash, arroyo, channel or other topographic feature on or over which waters flow at least periodically. Watercourse includes specifically designated areas in which substantial flood damage may occur. (Ord. 1318 § 1, 2001)

167

18.75.060 - Lands to which this chapter applies. This chapter shall apply to all areas of special flood hazards within the jurisdiction of the City of Rialto. (Ord. 1318 § 1, 2001) 18.75.070 - Basis for establishing the areas of special flood hazard. The areas of special flood hazard identified by the Federal Insurance Administration (FIA) of the Federal Emergency Management Agency (FEMA) in the Flood Insurance Study (FIS) dated June 2, 1995 and accompanying Flood Insurance Rate Maps (FIRMs) and Flood Boundary and Floodway Maps (FBFMs), dated June 2, 1995, and all subsequent amendments and/or revisions, are hereby adopted by reference and declared to be a part of this chapter. This FIS and attendant mapping is the minimum area of applicability of this chapter and may be supplemented by studies for other areas which allow implementation of this chapter, and which are recommended to the City Council by the Floodplain Administrator. The study, FIRMs and FBFMs are on file at The City of Rialto, Engineering Division, 150 South Palm Avenue, Rialto, CA, 92376. (Ord. 1318 § 1, 2001) 18.75.080 - Compliance. No structure or land shall hereafter be constructed, located, extended, converted, or altered without full compliance with the term of this chapter and other applicable regulations. Violation of the requirements (including violations of conditions and safeguards established in connection with conditions) of this chapter shall constitute a misdemeanor. Nothing herein shall prevent the City Council from taking such lawful action as is necessary to prevent or remedy any violation. (Ord. 1318 § 1, 2001) 18.75.090 - Abrogation and greater restrictions. This chapter is not intended to repeal, abrogate, or impair any existing easements, covenants, or deed restrictions. However, where this chapter and another ordinance, easement, covenant, or deed restriction conflict or overlap, whichever imposes the more stringent restrictions shall prevail. (Ord. 1318 § 1, 2001) 18.75.100 - Interpretation. In the interpretation and application of this chapter, all provisions shall be:

168
2023 LOCAL HAZARD MITIGATION PLAN
A. Considered as minimum requirements. B. Liberally construed in favor of the governing body; and C. Deemed neither to limit nor repeal any other powers granted under state statutes. (Ord. 1318 § 1, 2001) 18.75.110 - Warning and disclaimer of liability. The degree of flood protection required by this chapter is considered reasonable for regulatory purposes and is based on scientific and engineering considerations. Larger floods can and will occur on rare occasions. Flood heights may be increased by man-made or natural causes. This chapter does not imply that land outside the areas of special flood hazards or uses permitted within such areas will be free from flooding or flood damages. This chapter shall not create liability on the part of City Council, any officer or employee thereof, the State of California, or the Federal Insurance Administration, Federal Emergency Management Agency, for any flood damages that result from reliance on this chapter, or any administrative decision lawfully made hereunder. (Ord. 1318 § 1, 2001) 18.75.120 - Severability. This chapter and the various parts of the ordinance adopting the same are hereby declared to be severable. Should any section of this chapter be declared by the courts to be unconstitutional or invalid, such decision shall not affect the validity of this chapter as a whole, or any portion thereof other than the section so declared to be unconstitutional or invalid. (Ord. 1318 § 1, 2001) 18.75.130 - Establishment of development permit. A development permit shall be obtained before any construction or other development begins within any area of special flood hazard established in Section 18.75.070. Application for a development permit shall be made on forms furnished by the Floodplain Administrator and may include, but not be limited to: plans in duplicate drawn to scale showing the nature, location, dimensions, and elevation of the area in question; existing or proposed structures, fill, storage of materials, drainage facilities; and the location of the foregoing. Specifically, the following information is required. A. Site plan, including but not limited to:

169

1. For all proposed structures, spot ground elevations at building corners and twenty-foot or smaller intervals along the foundation footprint, or one foot contour elevations throughout the building site; and 2. Proposed locations of water supply, sanitary sewer, and utilities; and 3. If available, the base flood elevation from the Flood Insurance Study and/or Flood Insurance Rate Map; and 4. If applicable, the location of the regulatory floodway; and B. Foundation design detail, including but not limited to: 1. Proposed elevation in relation to mean sea level, of the lowest floor (including basement) of all structures; and 2. For a crawl-space foundation, location and total net area of foundation openings as required in Section 18.75.170 of this chapter and FEMA Technical Bulletins 1-93 and 7-93; and 3. For foundations placed on fill, the location and height of fill, and compaction requirements (compacted to ninety-five (95) percent using the Standard Proctor Test method); and C. Proposed elevation in relation to mean sea level to which any nonresidential structure will be flood proofed, as required in Section 18.75.170 of this chapter and FEMA Technical Bulletin TB 3-93; and D. All appropriate certifications listed in Section 18.75-150 of this chapter; and E. Description of the extent to which any watercourse will be altered or relocated as a result of proposed development. (Ord. 1318 § 1, 2001) 18.75.140 - Designation of the floodplain administrator. The City Engineer is hereby appointed to administer, implement, and enforce this chapter by granting or denying development permits in accord with its provisions. (Ord. 1318 § 1, 2001) 18.75.150 - Duties and responsibilities of the floodplain administrator. The duties and responsibilities of the Floodplain Administrator shall include, but not be limited to the following. A. Permit Review. Review all development permits to determine that:

170
2023 LOCAL HAZARD MITIGATION PLAN

1. Permit requirements of this chapter have been satisfied, 2. All other required state and federal permits have been obtained, 3. The site is reasonably safe from flooding, and 4. The proposed development does not adversely affect the carrying capacity of areas where base flood elevations have been determined but a floodway has not been designated. For purposes of this chapter, "adversely affects" means that the cumulative effect of the proposed development when combined with all other existing and anticipated development will increase the water surface elevation of the base flood more than one foot at any point. B. Review, Use and Development of Other Base Flood Data. 1. When base flood elevation data has not been provided in accordance with Section 18.75.070, the Floodplain Administrator shall obtain, review, and reasonably utilize any base flood elevation and floodway data available from a federal or state agency, or other source, in order to administer Sections 18.75.170 through 18.75.240 of this chapter. Any such information shall be submitted to the City Council for adoption; or 2. If no base flood elevation data is available from a federal or state agency or other source, then a base flood elevation shall be obtained using one of two methods from the FEMA publication "Managing Floodplain Development in Approximate Zone A Areas—A Guide for Obtaining and Developing Base (100-year) Flood Elevations" dated July 1995 in order to administer Sections 18.75.170 through 18.75.240 of this chapter: a. Simplified method i. 100 year or base flood discharge shall be obtained using the appropriate regression equation found in a U.S. Geological Survey publication, or the discharge-drainage area method; and ii. Base flood elevation shall be obtained using the Quick-2 computer program developed by FEMA; or b. Detailed method i. 100 year or base flood discharge shall be obtained using the U.S. Army Corps of Engineers' HEC-HMS computer program; and ii. Base flood elevation shall be obtained using the U.S. Army Corps of Engineers' HEC-RAS computer program. C. Notification of Other Agencies. In alteration or relocation of a watercourse:

171

1. Notify adjacent communities and the California Department of Water Resources prior to alteration or relocation. 2. Submit evidence of such notification to the Federal Insurance Administration, Federal Emergency Management Agency; and 3. Assure that the flood carrying capacity within the altered or relocated portion of said watercourse is maintained. D. Documentation of Floodplain Development. Obtain and maintain for public inspection and make available, as needed, the following: 1. Certification required by Section 18.75.170 C.1. (lowest floor elevations), 2. Certification required by Section 18.75.170 C.2 (elevation or flood proofing of nonresidential structures), 3. Certification required by Section 18.75.190 C.3 (wet floodproofing standard), 4. Certification of elevation required by Section 18.75.190 B (subdivision standards), 5. Certification required by Section 18.75.220 A (floodway encroachments), 6. Reports required by Section 18.75.240 C (mudflow standards). E. Map Determinations. Make interpretations where needed, as to the exact location of the boundaries of the areas of special flood hazard. Where there appears to be a conflict between a mapped boundary and actual field conditions, grade and base flood elevations shall be used to determine the boundaries of the special flood hazard area. The person contesting the location of the boundary shall be given a reasonable opportunity to appeal the interpretation as provided in Sections 18.75.250 through 18.75.270 of this chapter. F. Remedial Action. Take action to remedy violations of this chapter as specified in Section 18.75.080. (Ord. 1318 § 1, 2001) 18.75.160 - Appeals. The City Council of the City of Rialto shall hear and decide appeals when it is alleged there is an error in any requirement, decision, or determination made by the Floodplain Administrator in the enforcement or administration of this chapter. (Ord. 1318 § 1, 2001)

172
2023 LOCAL HAZARD MITIGATION PLAN

18.75.170 - Standards of construction. In all areas of special flood hazards the following standards are required: A. Anchoring 1. All new construction and substantial improvements shall be adequately anchored to prevent flotation, collapse or lateral movement of the structure resulting from hydrodynamic and hydrostatic loads, including the effects of buoyancy. 2. All manufactured homes shall meet the anchoring standards of Section 18.75.200. B. Construction materials and methods. All new construction and substantial improvement shall be constructed. 1. With flood resistant materials as specified in FEMA Technical Bulletin TB 2-93, and utility equipment resistant to flood damage. 2. Using methods and practices that minimize flood damage. 3. With electrical, heating, ventilation, plumbing and air conditioning equipment and other service facilities that are designed and/or located so as to prevent water from entering or accumulating within the components during conditions of flooding; and if 4. Within Zones AH or AO, so that there are adequate drainage paths around structures on slopes to guide flood waters around and away from proposed structures. C. Elevation and flood proofing. (See Section 18.75.050 definitions for "basement," "lowest floor," "new construction," "substantial damage" and "substantial improvement".) 1. Residential construction, new or substantial improvement, shall have the lowest floor, including basement, A. In an AO zone, elevated above the highest adjacent grade to a height equal to or exceeding the depth number specified in feet on the FIRM, or elevated at least two feet above the highest adjacent grade if no depth number is specified. (The State of California recommends that in AO zones without velocity the lowest floor be elevated above the highest adjacent grade to a height exceeding the depth number specified in feet on the FIRM by at least two feet or elevated at least four feet above the highest adjacent grade if no depth number is specified in feet on the FIRM by at least two feet or elevated at least four feet above the highest adjacent grade if no depth number is specified.)

173
B. In an A zone, elevated to or above the base flood elevation; said base flood elevation shall be determined by one of the methods in Section 18.75.150 B of this chapter. (The State of California recommends the lowest floor be elevated at least two feet above the base flood elevation, as determined by the community) C. In all other Zones, elevated to or above the base flood elevation. (The State of California recommends the lowest floor be elevated at least two feet above the base flood elevation.) Upon the completion of the structure, the elevation of the lowest floor including basement shall be certified by a registered professional engineer or surveyor and verified by the community building inspector to be properly elevated. Such certification and verification shall be provided to the Floodplain Administrator. 2. Nonresidential construction, new or substantial improvement, shall either be elevated to conform with Section 18.75.170 C.1 or together with attendant utility and sanitary facilities a. Be flood proofed below the elevation recommended under Section 18.75.170 C.1 so that the structure is watertight with walls substantially impermeable to the passage of water; b. Have structural components capable of resisting hydrostatic and hydrodynamic loads and effects of buoyancy; and c. Be certified by a registered professional engineer or architect that the standards of this section are satisfied. Such certification shall be provided to the Floodplain Administrator. 3. All new construction and substantial improvement with fully enclosed areas below the lowest floor (excluding basements) that are usable solely for parking of vehicles, building access or storage, and which are subject to flooding, shall be designed to automatically equalize hydrostatic flood forces on exterior walls by allowing for the entry and exit of floodwater. Designs for meeting this requirement shall follow the guidelines in FEMA Technical Bulletins TB 1-93 and TB 7-93, and must exceed the following minimum criteria: a. Have a minimum of two openings having a total net area of not less than one square inch for every square foot of enclosed area subject to flooding. The bottom of all openings shall be no higher than one foot above grade. Openings may be equipped with screens, louvers, valves or other coverings or devices provided that they permit the automatic entry and exit of floodwater; or b. Be certified by a registered professional engineer or architect.

174
2023 LOCAL HAZARD MITIGATION PLAN

4. Manufactured homes shall also meet the standards in Section 18.75.200. (Ord. 1318 § 1, 2001) 18.75.180. - Standards for utilities. A. All new and replacement water supply and sanitary sewage systems shall be designed to minimize or eliminate: 1. Infiltration of flood waters into the systems, and 2. Discharge from the systems into flood waters. B. On-site waste disposal systems shall be located to avoid impairment to them, or contamination from them during flooding. (Ord. 1318 § 1, 2001) 18.75.190 - Standards for subdivisions. A. All preliminary subdivision proposals shall identify the special flood hazard area and the elevation of the base flood. B. All subdivision plans will provide the elevation of proposed structure(s) and pad(s). If the site is filled above the base flood elevation, the lowest floor and pad elevations shall be certified by a registered professional engineer or surveyor and provided to the Floodplain Administrator. C. All subdivision proposals shall be consistent with the need to minimize flood damage. D. All subdivision proposals shall have public utilities and facilities such as sewer, gas, electrical and water systems located and constructed to minimize flood damage. E. All subdivisions shall provide adequate drainage to reduce exposure to flood hazards. (Ord. 1318 § 1, 2001) 18.75.200 - Standards for manufactured homes. A. All manufactured homes that are placed or substantially improved, within Zones A1-30, AH, and AE on the community's Flood Insurance Rate Map, on sites located: 1. Outside of a manufactured home park or subdivision, 2. In a new manufactured home park or subdivision, 3. In an expansion to an existing manufactured home park or subdivision, or

175

4. In an existing manufactured home park or subdivision on a site upon which a manufactured home has incurred "substantial damage" as the result of a flood, shall be elevated on a permanent foundation such that the lowest floor of the manufactured home is elevated to or above the base flood elevation (the State of California recommends at least two feet above the base flood elevation) and be securely fastened to an adequately anchored foundation system to resist flotation, collapse, and lateral movement. B. All manufactured homes to be placed or substantially improved on sites in an existing manufactured home park or subdivision within Zones A1-30, AH and AE on the community's Flood Insurance Rate Map that are not subject to the provisions of paragraph A of this section will be securely fastened to an adequately anchored foundation system to resist flotation, collapse, and lateral movement, and be elevated so that either the 1. Lowest floor of the manufactured home is at or above the base flood elevation (the State of California recommends at least two feet above the base flood elevation), or 2. Manufactured home chassis is supported by reinforced piers or other foundation elements of at least equivalent strength that are no less than 36 inches in height above grade. Upon the completion of the structure, the elevation of the lowest floor including basement shall be certified by a registered professional engineer or surveyor and verified by the community building-inspector to be properly elevated. Such certification and verification shall be provided to the Floodplain Administrator. (Ord. 1318 § 1, 2001) 18.75.210 - Standards for recreational vehicles. A. All recreational vehicles placed on sites within Zones A1-30, AH, and AE on the community's Flood Insurance Rate Map will either: 1. Be on the site for fewer than one hundred eighty consecutive days, and be fully licensed and ready for highway use- recreational vehicle is ready for highway use if it is on its wheels or jacking system, is attached to the site only by quick disconnect type utilities and security devices, and has no permanently attached additions, or 2. Meet the permit requirements of Sections 18.75.130 through 18.75.160 of this chapter and the elevation and anchoring requirements for manufactured homes in Section 18.75.200 A. (Ord. 1318 § 1, 2001) 18.75.220 - Floodways.

176
2023 LOCAL HAZARD MITIGATION PLAN
Located within areas of special flood hazard established in Section 18.75.070 are areas designated as floodways. Since the floodway is an extremely hazardous area due to the velocity of floodwaters, which carry debris, potential projectiles, and erosion potential, the following provisions apply. A. Prohibit encroachments, including fill, new construction, substantial improvement, and other new development unless certification by a registered professional engineer is provided demonstrating that encroachments shall not result in any increase in the base flood elevation during the occurrence of the base flood discharge. B. If Section 18.75.220 A is satisfied, all new construction, substantial improvement, and other proposed new development shall comply with all other applicable flood hazard reduction provisions of Sections 18.75.170 through 18.75.240 of this chapter. (Ord. 1318 § 1, 2001) 18.75.230 - Mudslide (I.E., mud ow) prone areas. A. The Floodplain Administrator shall review permits for proposed construction of other development to determine if it is proposed within a mudslide area. B. Permits shall be reviewed to determine that the proposed site and improvement will be reasonably safe from mudslide hazards. Factors to be considered in making this determination include but are not limited to the 1. Type and quality of soils, 2. Evidence of ground water or surface water problems, 3. Depth and quality of any fill, 4. Overall slope of the site, and 5. Weight that any proposed development will impose on the slope. C. Within areas which may have mudslide hazards, the floodplain Administrator shall require that: 1. A site investigation and further review be made by persons qualified in geology and soils engineering. 2. The proposed grading, excavation, new construction, and substantial improvement be adequately designed and protected against mudslide damages. 3. The proposed grading, excavations, new construction, and substantial improvement not

177
aggravate the existing hazard by creating either on-site of off-site disturbances; and 4. Drainage, planting, watering, and maintenance does not endanger slope stability. (Ord. 1318 § 1, 2001) 18.75.240 - Flood-related erosion-prone area. A. The Floodplain Administrator shall require permits for proposed construction and other development within all flood-related erosion-prone areas as known to the community. B. Permit applications shall be reviewed to determine whether the proposed site alterations and improvements will be reasonably safe from flood-related erosion and will not cause flood-related erosion hazards or otherwise aggravate the existing hazard. C. If a proposed improvement is found to be in the path of flood-related erosion or would increase the erosion hazard, such improvement shall be relocated, or adequate protective measures shall be taken to avoid aggravating the existing erosion hazard. D. Within Zone E on the Flood Insurance Rate Map, a setback is required for all new development from the ocean, lake, bay, riverfront or other body of water to create a safety buffer consisting of a natural vegetative or contour strip. This buffer shall be designated according to the flood related erosion hazard and erosion rate, in relation to the anticipated useful life of structures, and depending upon the geologic, hydrologic, topographic, and climatic characteristics of the land. The buffer may be used for suitable open space purposes, such as for agricultural, forestry, outdoor recreation and wildlife habitat areas, and for other activities using temporary and portable structures only. (Ord. 1318 § 1, 2001) 18.75.250 - Nature of variances. The variance criteria set forth in this section are based on the general principle of zoning laws that variances pertain to a piece of property and are not personal in nature. A variance may be granted for a parcel of property with physical characteristics so unusual that complying with the requirements of this chapter would create an exceptional hardship to the applicant or the surrounding property owners. The characteristics must be unique to the property and not be shared by adjacent parcels. The unique characteristic must pertain to the land itself, not to the structure, its inhabitants, or the property owners.

178
2023 LOCAL HAZARD MITIGATION PLAN
It is the duty of the City Council to help protect its citizens from flooding. This need is so compelling and the implications of the cost of insuring a structure built below flood level is so serious that variances from the flood elevation or from other requirements in this chapter are quite rare. The long-term goal of preventing and reducing flood loss and damage can only be met if variances are strictly limited. Therefore, the variance guidelines provided in this chapter are more detailed and contain multiple provisions that must be met before a variance can be properly granted. The criteria are designed to screen out those situations in which alternatives other than a variance are more appropriate. (Ord. 1318 § 1, 2001) 18.75.260 - Appeal board. A. In passing upon requests for variances, the City Council shall consider all technical evaluations, all relevant factors, standards specified in other sections of this chapter, and the 1. Danger that materials may be swept onto other lands to the injury of others. 2. Danger of life and property due to flooding or erosion damage. 3. Susceptibility of the proposed facility and its contents to flood damage and the effect of such damage on the existing individual owner and future owners of the property. 4. Importance of the services provided by the proposed facility to the community. 5. Necessity to the facility of a waterfront location, where applicable. 6. Availability of alternative locations for the proposed use which are not subject to flooding or erosion damage. 7. Compatibility of the proposed use with existing and anticipated development. 8. Relationship of the proposed use to the comprehensive plan and floodplain management program for that area. 9. Safety of access to the property in time of flood for ordinary and emergency vehicles. 10. Expected heights, velocity, duration, rate of rise, and sediment transport of the flood waters expected at the site; and 11. Costs of providing governmental services during and after flood conditions, including maintenance and repair of public utilities and facilities such as sewer, gas, electrical, and water system, and streets and bridges.

179
B. Any applicant to whom a variance is granted shall be given written notice over the signature of a community official that: 1. The issuance of a variance to construct a structure below the base flood level will result in increased premium rates for flood insurance up to amounts as high as twenty-five dollars ($25.00) for one hundred dollars ($100.00) of insurance coverage, and 2. Such construction below the base flood level increases risks to life and property. It is recommended that a copy of the notice shall be recorded by the Floodplain Administrator in the Office of the San Bernardino County Recorder and shall be recorded in a manner so that it appears in the chain of title of the affected parcel of land. C. The Floodplain Administrator will maintain a record of all variance actions, including justification for their issuance, and report such variances issued in its biennial report submitted to the Federal Insurance Administration, Federal Emergency Management Agency. (Ord. 1318 § 1, 2001) 18.75.270 - Conditions for variances. A. Generally, variances may be issued for new construction, substantial improvement, and other proposed new development to be erected on a lot of one-half acre or less in size contiguous to and surrounded by lots with existing structures constructed below the base flood level, providing that the procedures of Sections 18.75.130 through 18.75.240 of this chapter have been fully considered. As the lot size increases beyond one-half acre, the technical justification required for issuing the variance increases. B. Variances may be issued for the repair or rehabilitation of "historic structures" (as defined in Section 18.75.050 of this chapter) upon a determination that the proposed repair or rehabilitation will not preclude the structure's continued designation as a historic structure and the variance is the minimum necessary to preserve the historic character and design of the structure. C. Variances shall not be issued within any mapped regulatory floodway if any increase in flood levels during the base flood discharge would result. D. Variances shall only be issued upon a determination that the variance is the "minimum necessary" considering the flood hazard, to afford relief "Minimum necessary" means to afford relief with a minimum of deviation from the requirements of this chapter. For example, in the case of variances to an elevation requirement, this means the City Council need not grant permission for the applicant to build at grade, or even to whatever elevation the applicant

180
2023 LOCAL HAZARD MITIGATION PLAN
proposes, but only to that elevation which the City Council believes will both provide relief and preserve the integrity of this chapter. E. Variances shall only be issued upon a 1. Showing of good and sufficient cause. 2. Determination that failure to grant the variance would result in exceptional "hardship" (as defined in Section 18.75.050 of this chapter) to the applicant; and 3. Determination that the granting of a variance will not result in increased flood heights, additional threats to public safety, or extraordinary public expense, create a nuisance (as defined in Section 18.75.050—see "Public safety and nuisance"), cause fraud or victimization (as defined in Section 18.75.050) of the public, or conflict with existing local laws or ordinances. F. Variances may be issued for new construction, substantial improvement, and other proposed new development necessary for the conduct of a functionally dependent use provided that the provisions of Sections 18.75.270, A through E, are satisfied and that the structure or other development is protected by methods that minimize flood damages during the base flood and does not result in additional threats to public safety and does not create a public nuisance. G. Upon consideration of the factors of Section 18.75.260 A and the purposes of this chapter, the City Council may attach such conditions to the granting of variances as it deems necessary to further the purposes of this chapter. (Ord. 1318 § 1, 2001)

181
Appendix D: Public Engagement Survey Results

182
2023 LOCAL HAZARD MITIGATION PLAN

183

184
2023 LOCAL HAZARD MITIGATION PLAN

185

186
2023 LOCAL HAZARD MITIGATION PLAN

187

188
2023 LOCAL HAZARD MITIGATION PLAN

189

190
2023 LOCAL HAZARD MITIGATION PLAN

191

192
2023 LOCAL HAZARD MITIGATION PLAN

193

194
2023 LOCAL HAZARD MITIGATION PLAN

195

196
2023 LOCAL HAZARD MITIGATION PLAN