Officials from the Metropolitan Water District, the City of Pasadena, and the City of Glendale recently traveled to Sacramento, the Sacramento-San Joaquin Delta, and the Central Valley to inspect dams, reservoirs, farms, and State and Federal Water Project infrastructure to learn about how water is delivered to Southern California and about challenges to that system.

The Metropolitan Water District of Southern California is one of the world’s largest water agencies. From the Colorado River and from Northern California through the State Water Project, Metropolitan imports more than half of all the water used by nearly 19 million consumers in its six-county service area. Metropolitan is the wholesale water provider to 26 member public agencies, which, along with about 130 sub-agencies, deliver the water to homes, businesses, and agriculture in Metropolitan’s 5,200-square-mile service area, including Pasadena.

Oroville Dam & Fish Hatchery

Oroville Dam is on the Feather River above the city of Oroville in Butte County, California. It creates Lake Oroville, generates electricity, and provides drinking and irrigation water for Central and Southern California. The dam, lake, and other facilities are owned and operated by the state Department of Water Resources and are part of the State Water Project.

The State Water Project is the largest state-built and operated multi-purpose water and power system in the United States. In addition to providing water to 27 million Californians and 750,000 acres of farmland, the project generates power, provides year-round recreation and flood protection, enhances fish and wildlife habitat, and helps maintain water quality and control saltwater intrusion in the Sacramento-San Joaquin Delta. The project includes 705 miles of canals, tunnels, and pipelines, 444 miles of California Aqueduct, 36 storage facilities, 26 dams, 21 pumping plants, four pumping-generating plants, and five hydroelectric plants.

California’s history, landscape, and economy have been shaped by water. To address nature’s water imbalance and allow for growth, water has to be transferred from where it is plentiful to where it is needed. Californians provided the solution with passage of the 1960 California Water Resources Development Bond Act, which authorized $1.75 billion for construction of the State Water Project.

Construction of Oroville Dam altered the Feather River and a portion of spawning and nursery grounds were lost to Chinook salmon and steelhead trout returning to their home stream to deposit eggs. To compensate for this loss, the Feather River Fish Hatchery was opened in 1967 south of Oroville Dam.

The hatchery facility—one of the most advanced and successful fish hatcheries in California—was cooperatively planned by the Department of Fish and Wildlife and the Department of Water Resources to intervene to help ensure the continuation of spring and fall run salmon and trout. The fish are raised at the hatchery and released in the Feather River or San Francisco Bay to find their way to the Pacific Ocean where they mature. After two to three years in the ocean, they instinctively return to their natal origins—through the Sacramento-San Joaquin Delta, up the Sacramento River to the Feather River Fish Hatchery.

In 2017, a major flood at Oroville Dam caused enormous damage, so a massive spillway was built, an impressive engineering feat.

Sites Reservoir

Sites Reservoir is an innovative 21st century water project, a proposed off-stream reservoir located northwest of Sacramento that would provide 470,000 to 640,000 acre-feet of water storage and improve water supply reliability and flexibility in the system. The goal is to save water for the future by capturing water during high runoff, and then saving this water for various beneficial uses at a later time.

A number of agencies are investors/partners in the project, including the Metropolitan Water District. Each agency would own a certain proportion of the water in the reservoir, should it ever get built. There is a growing list of agencies on the waiting list.

The Joint Project Authority, which is managing and planning the project and consists of seven regional entities including several local water agencies and counties, is coordinating with 30 landowners in the proposed, sparsely populated area of the reservoir. Land and water rights acquisitions are anticipated to begin in 2024.

Sacramento-San Joaquin Delta

About 30 percent of the water that flows to taps in Southern California homes and businesses originates in Northern California watersheds and flows through the Sacramento-San Joaquin Delta. The Department of Water Resources is leading the effort to modernize the Delta’s infrastructure to withstand a growing list of challenges. This includes the Delta’s declining ecosystem and 1,100 miles of levees that are increasingly vulnerable to earthquakes, flooding, saltwater intrusion, subsidence, sea level rise, the impacts of climate change, and other environmental degradation.

Saltwater from the San Francisco Bay mixes with fresh water from the Sacramento, San Joaquin, and other rivers to create the largest estuary on the West Coast with habitat critical to the survival of many fish and wildlife species. The Delta is also a rich agricultural area that supports a $32 billion agricultural industry and a wide range of recreational opportunities.

The group heard a presentation by Delta expert Curt Schmutte, who argued that the Delta is not sustainable, and will be unusable by the end of the century if the sea level continues to rise. The Delta is the hub of California’s water supply system and the home to hundreds of animal, fish, and bird species, many of which are non-native. The Delta used to be a wild, natural area; in the 1880s to 1930s, humans built levees (mostly by Chinese labor) for farming, resulting in an enormous transformation of the area and destroying 90 percent of the food supply for local species. To maintain a healthy water supply and increase the amount of fish, we need to improve the Delta’s ecosystem and make it more natural. It will require $1 billion to restore the balance of food and habitat.

Schmutte proposes large, twin tunnels underneath the Delta, sandy beaches, and floating marshes to overcome some of the challenges facing the Delta region.

San Luis Reservoir

On August 18, 1962, President John F. Kennedy led the official groundbreaking ceremonies for the San Luis Joint-Use Complex. The event was the result of a 1961 agreement between California and the federal government to build the facilities, since both state and federal water projects required the development of the B.F. Sisk San Luis Dam site for storage of flows pumped from the Sacramento-San Joaquin Delta. The agreement integrated storage, pumping-generating, and conveyance facilities for state and federal water operations. Construction of the Sisk and O’Neill dams began in 1963 and was completed in 1967.

Located in the eastern foothills of the Diablo Mountain Range, San Luis Reservoir is the largest off-stream reservoir in the United States (an off-stream reservoir is one that is filled with water pumped from a source other than its natural watershed). San Luis Reservoir holds water originally captured from rainfall and snowmelt stored in Shasta Lake and Lake Oroville that flows through the Delta and is pumped into the California Aqueduct and the Delta-Mendota Canal. The reservoir can store 2,027,840 acre-feet of water (an acre-foot is 325,851 gallons, often described as the amount of water two families use in a year).

Water in the mainstem of the California Aqueduct flows south by gravity into the San Luis Joint-Use Complex, which was designed and constructed by the federal government and is operated and maintained by the Department of Water Resources. Within the complex are O’Neill Forebay, Sisk Dam and San Luis Reservoir, the nation’s largest off-stream reservoir (it has no natural watershed), the Gianelli Pumping-Generating Plant, Dos Amigos Pumping Plant, and the San Luis Canal. This section of the California Aqueduct serves both the State Water Project and the federal Central Valley Project.

The San Luis Reservoir is currently at 68 percent capacity. Usually at this time of year, it is at 30 percent capacity. The reservoir can hold 2.1 million acre feet, and 65 million gallons are lost every day to evaporation. About 55 percent of the water in the reservoir is Southern California’s drinking water. Construction is underway to raise the reservoir by 10 feet and make it earthquake safe.

Del Bosque Farms

The group visited Del Bosque Farms on the Great Westside of the San Joaquin Valley. Owner Joe Del Bosque is a grower of fresh, organic fruits, nuts, and vegetables, and one of the largest organic melon farmers in the United States. His biggest client for his organic watermelons, cantaloupe, and honeydew melons is Whole Foods. He explained that to be certified organic, a farm’s soil must be free of pesticides for three years.

He is an advocate for agriculture, water supply, and for farm workers, and he served on the California Water Commission. The son of a migrant farm worker, he earned his way through college as a farm worker, and his wife, Maria Gloria Del Bosque, is a former migrant worker who immigrated to the United States with her family.

Del Bosque explained about senior and junior water rights in the Central Valley that date back more than a century, before 1914. The rights stay with the land, even if a farmer sells their property. A piece of property with junior water rights could go for about $7,000 per acre, while a piece of property right next door with senior water rights could go for about $30,000 per acre.

He also talked about Prop 1, a water bond passed in 2014 that provides $7.5 billion for water projects, $2.5 billion of which is for water storage, which he said is not nearly enough.

He said the Central Valley grows a quarter of all food in the United States. It has unique soil and climate, which, along with water supply systems such as the state and federal water projects, make this region a particularly perfect place to grow food. Farmers grow tomatoes (95% of all tomatoes are grown in California), garlic (grown here and then shipped to Gilroy in Fresno County), onions, pomegranates, melons, pistachios, almonds, dairy/meat, olives, grapes, citrus, figs, berries, walnuts, lettuce, cotton, and much more.

California grows more citrus than Florida and more peaches than Georgia, and the Central Valley grows more grapes than Napa Valley. One hundred percent of almonds in the United States are grown in the Central Valley, and 70 percent of almonds in the entire world are grown in California. There used to be 1.2 million acres of cotton grown in California; that has decreased to 200,000 acres, having been replaced by other crops, mostly almonds, which use more water.

California is home to roughly 68,400 farms, which harvest approximately 15.8 million acres of farmland and produce about $51.1 billion in farm product sales. California farms dedicate approximately 25.8 million acre-feet of water to grow food and fiber, contribute about $89 billion to the economy every year, and employ more than 829,000 people per year.

View more photos from the trip below: