Introduction to the San Jacinto Tunnel
Thousands of feet below the snowy summit of Mt. San Jacinto, a formidable feat of engineering and grit makes life as we know it in Southern California possible. The 13-mile-long San Jacinto Tunnel was bored through the mountain in the 1930s by a crew of about 1,200 men who worked day and night for six years, blasting rock and digging with machinery. Completed in 1939, the tunnel was a cornerstone in the construction of the 242-mile Colorado River Aqueduct. It enabled the delivery of as much as 1 billion gallons of water per day.
The Tunnel’s Construction
The tunnel is usually off-limits when it is filled and coursing with a massive stream of Colorado River water. But recently, while it was shut down for annual maintenance, the Metropolitan Water District of Southern California opened the west end of the passage to give The Times and others a rare look inside. “It’s an engineering marvel,” said John Bednarski, an assistant general manager of MWD. “It’s pretty awe-inspiring.” The 16-foot-diameter San Jacinto Tunnel runs 13 miles through the mountain. While shut down for maintenance, the tunnel has a constant stream of water entering from the mountain.
Pipelines and Tunnels
The search for a route to bring Colorado River water across the desert to Los Angeles began with the signing of a 1922 agreement that divided water among seven states. After the passage of a $2-million bond measure by Los Angeles voters in 1925, hundreds of surveyors fanned out across the largely roadless Mojave and Sonoran deserts to take measurements and study potential routes. The surveyors traveled mostly on horseback and on foot as they mapped the rugged terrain, enduring grueling days in desert camps where the heat sometimes topped 120 degrees. Planners studied and debated more than 100 potential paths before settling on one in 1931.
Death and Delays
According to the MWD’s records, 13 workers died during the tunnel’s construction, including men who were struck by falling rocks, run over by equipment or electrocuted with a wire on one of the mining trolleys that rolled on railroad tracks. The Metropolitan Water District had originally hired Wenzel & Henoch Construction Co. to build the tunnel. But after less than two years, only about two miles of the tunnel had been excavated, and the contractor was fired by MWD general manager Frank Elwin “F.E.” Weymouth, who assigned the district’s engineers and workers to complete the project. Construction was delayed again in 1937 when workers went on strike for six weeks.
The Magic Touch of Water
By the time the tunnel was completed, the Metropolitan Water District had released a 20-minute film that was shown in movie theaters and schools celebrating its conquest of the Colorado River and the desert. It called Mt. San Jacinto the “tallest and most forbidding barrier.” In a rich baritone, the narrator declared Southern California “a new empire made possible by the magic touch of water.” Water began to flow through the aqueduct in 1939 as the pumping plants were tested. At the Julian Hinds Pumping Plant, near the aqueduct’s halfway point, water was lifted 441 feet, surging through three pipelines up a desert mountain.
An Impressive Design
Today, 19 million people depend on water delivered by the MWD, which also imports supplies from Northern California through the aqueducts and pipelines of the State Water Project. In recent decades, the agency has continued boring tunnels where needed to move water. A $1.2-billion, 44-mile-long conveyance system called the Inland Feeder, completed in 2009, involved boring eight miles of tunnels through the San Bernardino Mountains and another 7.9-mile tunnel under the Badlands in Riverside County. The system enabled the district to increase its capacity and store more water during wet years in Diamond Valley Lake, Southern California’s largest reservoir, which can hold about 260 billion gallons of water.
Conclusion
The San Jacinto Tunnel is a testament to the ingenuity and determination of the engineers and workers who built it. Despite the challenges and delays, the tunnel was completed in 1939 and has been delivering water to Southern California ever since. The tunnel’s design and construction are a remarkable achievement, and it continues to play a vital role in the region’s water supply.
FAQs
Q: How long is the San Jacinto Tunnel?
A: The San Jacinto Tunnel is 13 miles long.
Q: When was the tunnel completed?
A: The tunnel was completed in 1939.
Q: How much water can the tunnel deliver per day?
A: The tunnel can deliver up to 1 billion gallons of water per day.
Q: Who built the tunnel?
A: The tunnel was built by a crew of about 1,200 men who worked for the Metropolitan Water District of Southern California.
Q: What is the purpose of the tunnel?
A: The tunnel is part of the Colorado River Aqueduct, which delivers water from the Colorado River to Southern California.
Q: How many people depend on the water delivered by the MWD?
A: 19 million people depend on the water delivered by the MWD.
Q: What is the name of the conveyance system that was completed in 2009?
A: The Inland Feeder.
Q: How much did the Inland Feeder cost to build?
A: The Inland Feeder cost $1.2 billion to build.
