Tunnel breakthrough marks milestone in California metropolitan water quality project

A 250-ton mechanical mole punched through the earth's surface today, leaving in its wake a large-diameter tunnel, eight miles long, to serve as a critical water line for Southern California.

REDLANDS, Calif., July 27, 2001 — With a loud roar and a cascade of dirt, a 250-ton mechanical mole punched through the earth's surface today, leaving in its wake a large-diameter tunnel, eight miles long, to serve as a critical water line for Southern California.

The breakthrough completes the 220-foot-long tunnel boring machine's year-and-a-half journey through the rocks and dirt up to 800 feet beneath the Badlands mountain range in Riverside and San Bernardino counties, as part of Metropolitan Water District's Inland Feeder project.

"Today, Metropolitan breaks through not just to the other side of the mountain, but to the future," said Phillip J. Pace, chairman of MWD's board of directors. "This is an important milestone for our Inland Feeder project, a vital link in securing a more reliable, higher-quality water supply for Southern Californians, while helping to protect the environment in Northern California."

The Badlands tunnel is the longest of three tunnels needed for the nearly 44-mile-long Inland Feeder, a high-capacity, gravity-fed water delivery system stretching from the foothills of the San Bernardino Mountains to the Colorado River Aqueduct in the Riverside County community of San Jacinto.

When completed in 2007, the Inland Feeder will offer Metropolitan the flexibility to deliver water from the San Francisco Bay/ Sacramento-San Joaquin Delta in Northern California during strategic times — primarily during the winter when water is abundant and when it will minimize impacts to its ecosystem.

The feeder also will improve the quality of Southern California's water supply by allowing more uniform blending of water from the state project with Colorado River supplies, which have a higher mineral content.

"Southern California is facing increasingly limited periods of time when water can be drawn from the Bay/Delta and delivered to our region," Pace said. "So when water is available, we must be prepared to move large volumes of water during a relatively short time, and then store them for use during dry periods and emergencies."

First envisioned nearly 15 years ago, the Inland Feeder will deliver water to be stored in surface reservoirs, such as MWD's Diamond Valley Lake near Hemet in southwest Riverside County, and groundwater basins for later use.

The project will help lessen the impact on the delicate ecosystem of the Bay/Delta estuary by enabling Metropolitan to take water during high flows. Studies show that during high-flow periods, significant amounts of fresh water flow into the ocean through the San Francisco Bay.

Dr. William J. Patzert, noted climate change expert and research oceanographer of NASA's Jet Propulsion Laboratory in Pasadena, said the Inland Feeder can help Southern California cope with future weather pattern uncertainties, which may bring more rain and less snowpack to Northern California, and longer periods of drought to Southern California.

"History shows that changes in climate and weather are inevitable, bringing significant uncertainties in our climate future and our water demands," Patzert said.

"Projects like the Inland Feeder will help accommodate the inevitable changes in climate and weather our region will experience. By understanding our climate past and carefully considering our climate future, Metropolitan has made a thoughtful investment in all our futures."

With the completion of the Badlands dig, the Inland Feeder project stands nearly 70 percent complete. The two additional tunnels — each about five miles long — to be burrowed beneath the San Bernardino National Forest have been put out to bid, with construction expected to begin in early 2003.

The Metropolitan Water District of Southern California is a cooperative of 26 cities and water agencies serving 17 million people in six counties. The district imports water from the Colorado River and Northern California to supplement local supplies, and helps its members to develop increased water conservation, recycling, storage and other water-management programs.

For more about this story, visit Metropolitan's Web site at http://www.mwdH2O.com.

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