Item 26 - Adoption of the City of Santa Ana Emergency Operations Plan

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City of Santa Ana Emergency Operations Plan Part I Basic Plan 2.4.13 Drought/Water Failure Water Supply and Water Needs Water supply in the city of Santa Ana is provided by the Santa Ana Public Works Agency's Water Resources Division. The City delivers an average of 33 million gallons per day, over 12 billion gallons per year, to approximately 45,000 customers. (A customer refers to a billing account, not an individual person, so each "customer" may serve a whole household or an entire business, school or other facility.) The City supplies water to the entire residential population of the City (more than 342,000 people) as well as serving approximately 9,000 non-residential, business or industrial customers. Domestic water supply (clean drinking water) is one of the most vital necessities that every human being depends on every day to sustain life and health. Residential consumers depend on water to drink, to prepare food, for personal health and hygiene, and to clean homes and belongings. Pets and service animals are just as dependent on daily drinking water. Most businesses, offices, retail stores, schools and other non -industrial water customers have similar daily water needs and many cannot function without a continual water supply. Hospitals and health care facilities depend on uninterrupted water supply to (in addition to the residential uses listed above) maintain surgery, laboratory and other medical treatment functions and to perform lifesaving medical care. For example, persons requiring kidney dialysis may require the procedure every one to three days and missing a dialysis session can cause death within about one day, and up to 100 gallons of water are required to perform a dialysis treatment. Another primary use of water supply is firefighting. Firefighters depend on water supplied to fire hydrants throughout the City, at sufficient pressure, to combat structural or other fires. A large structure fire may require hundreds of thousands of gallons of water to fully extinguish. Santa Ana receives its water supply from a combination of groundwater wells (approximately 75% of supply) and imported water (approximately 25% of supply). Water supply to Orange County as a whole is split close to 50%- 50% between groundwater and imported water, with south Orange County almost entirely dependent on water imported from outside the region. Groundwater wells accumulate rainfall and other water runoff that drains or is absorbed into the ground. The City owns 20 groundwater wells, which can provide up to 74 million gallons per day. In 2015, the City withdrew over 8 billion gallons from its groundwater wells. The City receives its imported water from the Metropolitan Water District of Southern California (MWD). MWD is a multi jurisdictional, cooperative agency that coordinates the delivery of water imported to southern California and distributed throughout Orange, Los Angeles, Ventura, San Bernardino, Riverside and San Diego Counties. MWD imports water from two primary sources: from the Colorado River to our east and from the California Aqueduct which brings water primarily from snowpack runoff from the Sierra Nevada Range in northern California. MWD can provide up to 87 million gallons per day and the City imported approximately 2.6 billion gallons in 2015. The City can store up to 49.3 million gallons in 10 City -owned tanks or reservoirs, and utilizes seven pumping stations and 444 miles of water mains to distribute the water throughout the City. Causes of Water Outages Three primary causes could prevent the City from delivering water to consumers: drought, damage to water supply lines, and water contamination. Drought - Drought is the largest threat to water supply. Unlike most natural disasters, drought is not a sudden, catastrophic occurrence; it is a gradually progressive event. Droughts occur over several years and it is often difficult to establish when they begin and end. California rarely has an "average" rainfall year; rainfall frequently varies from very wet to very dry years. Impacts of drought vary from region to region and among different populations, such as residents, industries and agriculture. Drought can be defined in different ways: by precipitation levels, snowpack depth, soil moisture or reservoir or groundwater levels. Generally, drought is a 102