Seventy-five years ago this year, water from the Colorado River Aqueduct was first delivered to a rapidly growing and thirsty Southern California, keeping a promise made to voters in the depth of the Great Depression.
The milestone culminated a years-long construction effort by the Metropolitan Water District of Southern California. The district was formed in 1928 for the purpose of building the great aqueduct across hundreds of miles of sun-baked desert to bring Colorado River water to the young and vibrant metropolis. Decades later, the effort still stands as an historic engineering and construction achievement.
Why we need the water – pro-Colorado River Aqueduct bond map.
The project would employ 35,000 men, who labored 24/7 in grueling Mojave Desert heat, erecting four dams and five pumping plants, blasting 90-plus miles of tunnels and constructing 150 miles of canals, siphons, conduit and pipelines.
On June 17, 1941 a valve was turned from the new Weymouth Treatment Plant and for the first time water followed to the city of Pasadena, one of the original 13 cities whose voters in 1931 overwhelmingly approved a $220 million bond measure to finance aqueduct construction (that would be $3.5 billion today). By the end of July, water would flow to Beverly Hills, Burbank, Compton and Santa Monica. Orange County would soon follow.
As the final countdown began to delivery day, it was a time of promise and uncertainty. Slugger Joe DiMaggio was in the middle of his 56-game hitting streak and heavyweight champion Joe Louis was racking up a string of knockouts. Glenn Miller and Duke Ellington were cutting records like “Chattanooga Choo-Choo” and “Take the A-Train.” It was the debut of Captain America, Cheerios and Chanel No. 5.
The first commercial TV broadcasts were weeks away. Across the Atlantic Ocean, World War II raged from Belgium to Britain as the Nazis tightened their grip on much of Europe. For weeks, America had been in a state of emergency because of Axis threats, and six months later, the Pearl Harbor attack would plunge the nation into war.
The aqueduct provided crucial support to the war effort, and years after the war ended, each generation of Southern Californians has risen to the challenge of preserving water reliability to a region and its industries that took their place on the world’s stage.
When drought struck the region in the 1940s and 1950s, agencies from Ventura, San Diego and the Inland Empire joined Metropolitan, which spread water reliability to an area that today stands at 5,200 square miles.
In 1960, Metropolitan threw its support behind the new State Water Project. In the 1970s, Metropolitan continued to evolve, expanding its complex distribution system to bring imported water from both Northern California and the Colorado River.
After drought again challenged the region in the late 1980s and early 1990s, Metropolitan’s member agencies committed the district to diversifying its water supplies through the Integrated Water Resources Plan. The amount of water preserved through conservation, water recycling and recovery is now the equivalent to filling a new Colorado River Aqueduct.
In 2000, Metropolitan finished Diamond Valley Lake, the largest reservoir in Southern California, helping the Southland secure a six-month emergency supply. As the Colorado River entered an historic drought, Metropolitan maintained reliability through the development of an innovative mix of exchange, transfer and storage agreements throughout the state and along the Colorado River.
Since the state’s historic drought began four years ago, Southern California has endured and thrived, using a combination of record water reserves and the nation’s largest water conservation rebate program. Metropolitan continues to pursue solutions in the San Joaquin-Sacramento Delta that balances environmental protection with water-supply reliability. At the same time, the district is pursuing development of a major water recycling partnership with Los Angeles County Sanitation Districts.
The heroic efforts that sent water across the desert and flowing into Southern California 75 years ago have inspired Metropolitan and its 26 member public agencies to make sure the promise of water reliability is one that will always be kept.
View Metropolitan's historical photo gallery and video.
A map of the Aqueduct route from the Colorado River to the Coastal Plain of Southern California and the thirteen cities.
Using social media to bring history to life, Metropolitan will be “live-tweeting” as if it were the Depression years counting down to June 1941. Learn about the men and women who worked on the Colorado River Aqueduct. Starting March 2016 until mid-June 2016, we will be sharing their stories on Twitter (@mwdh2o_75years). Through their “voices” you will learn about their lives, the challenges they faced and how each of them contributed to the success of a massive, unprecedented effort. Follow us at
Read more about the featured men and women
Dec. 29, 1928 –
First meeting held of the board of directors of the Metropolitan Water District.
Oct. 29, 1929 – Stock market crash; Great Depression begins.
1931 – Metropolitan's Board of Directors approves the
Parker route (Jan. 16); Southern California voters approve a $220 million measure to build the
Colorado River Aqueduct, with 82 percent voting yes (Sept. 29). That would be about $3.5 billion today.
Jan. 25, 1933 – Construction begins on the Colorado River Aqueduct as the first crew of workers arrives in the foothills of Coachella Valley.
Nov. 10, 1934 – Eight months after "Arizona Navy" attempts to block construction of Parker Dam, Arizona's governor attempts to put construction site under martial law. Congress clears way for dam construction the following year.
July 22, 1935 – Colorado River Aqueduct pioneer
William Mulholland dies. Several days later,
workers pay silent tribute to Mulholland along the aqueduct.
1936-37 – Construction begins on Gene pumping plant; first CRA pumping plant completed at Iron Mountain.
1938 – Completion of Cajalco Reservoir, Metropolitan's first storage reservoir and terminus for the Colorado River Aqueduct.
1939 – First Colorado River water delivered into the Colorado River Aqueduct (Jan. 7); the 13-mile San Jacinto Tunnel is completed, capping six years of floods and labor woes (Nov. 29).
1940 – One year it receives its first Colorado River water,
Cajalco Reservoir is renamed Lake Mathews in honor of W.B. Mathews, Metropolitan's first general counsel.
1941 – First water flows into the softening and filtration plant at La Verne, which will soon be renamed for Metropolitan chief engineer F.E. Weymouth,
who passes away within a few weeks after deliveries begin.
June 17, 1941 – Metropolitan water arrives in Pasadena marking the first delivery of Colorado River water to Southern California cities.
Dec. 7, 1941 – Japanese attack on Pearl Harbor. Metropolitan responds by adding surveillance of the Colorado River Aqueduct.