Photos by Tom Bleicher

At the exciting breakthrough event last August, several hundred people sat on bleachers near Cal State San Bernardino waiting expectantly in the mid-day sunshine.  The group included the crew, the contractors, directors, executive management, community leaders and others.

Then the ground began to rumble and rock started to fall from a spot on the mountain’s face, and as the spot became a hole, “Star Wars” music blasted over loudspeakers and the onlookers clapped and cheered as an 820-ton, 450-foot-long monster mechanical mole pushed its way out of the Devil Canyon portal of the Arrowhead West Tunnel of Metropolitan’s Inland Feeder project.

The Inland  Feeder Tunnel will be completed in November, culminating the tunnel boring machine’s six-year-long journey through the belly of the San Bernardino Mountains, and providing the final link to the 44-mile long stretch of gravity-fed tunnels and buried pipelines that carry State Water Project supplies into storage at Diamond Valley Lake.  Along the way, the crew and the machine dealt successfully with fires, floods, high groundwater and earthquake faults.

Photo by Tom Bleicher

“The Inland Feeder is possibly more important to urban Southern California now than it was when it was conceived 20 years ago,” said Metropolitan General Manager Jeff Kightlinger.

“The Sacramento-San Joaquin Delta has become even more environmentally fragile,” Kightlinger said,   “and court-sanctioned environmental regulations to protect endangered fish have severely curtailed pumping water from the Delta.

“So when the state’s pumps can send us water, we want to be able to move it into storage in Diamond Valley Lake as quickly as we can, and that’s what the Inland Feeder will do for us.”

The Inland Feeder has had its glory moments: starring roles on the popular television shows “Modern Marvels” and “Tactical to Practical” on the History Channel, and Discovery Channel’s “Build It Bigger.” 

 The $1.2-billion project has also had its share of challenges, including groundwater so high that at times it seemed like tunneling through a lake; gaining approvals from the U.S. Forest Service; and moments of despair, especially Christmas Day morning of 2003, when heavy rains caused mudslides and  flooded the West Tunnel  causing a four-month shutdown for cleanup and repairs.

However, those events faded away as the German-built, laser-guided tunnel boring machine broke through the Devil Canyon Portal and completed the last of the tunneling. 

The Inland Feeder consists of three separate tunnels—the 8-mile Riverside Badlands Tunnel, completed in July 2001; the 5.8-mile Arrowhead East,  completed in May 2008, and the 3.8-mile Arrowhead West—together totaling 18 miles. There’s another 26 miles of buried pipeline.  The Inland Feeder stretches from the East Branch of the State Water Project just below Silverwood Lake (north of San Bernardino), 44 miles south to connect with various pre-existing pipelines and aqueducts leading into Diamond Valley Lake in Hemet.

Photo by Rick Ravenstine

The tunnels were excavated to 19 feet in diameter by the TBM.  Next, precast concrete liners, mortar and steel pipes were installed.  With the insertion of steel pipes through the lengths of the tunnels, the finished diameter of the 44-mile Inland Feeder will be 12 feet, capable of delivering about 1,000 cubic feet per second, or about 646 million gallons a day.

Inland Feeder construction crews are currently lining the tunnels with steel pipe and are expected to complete the pipe-lining and backfill grouting by this fall.  Portal structures—concrete buildings built over the pipeline so it can be shut down, dewatered and entered for inspection and repair—are being built at three of the four portals, and also are expected to be done by late fall.

The entire 44-mile long facility is expected to be ready to carry water by this Thanksgiving—more than a year ahead of schedule.  Actually, portions of the project are already carrying water; since 2003 more than 620,000 acre-feet of SWP water has been delivered to Diamond Valley Lake through a connection with a San Bernardino Valley Municipal Water District pipeline.

Photo by Tom Bleicher

Of all the sections, the West Tunnel posed the most challenges. 

In late October 2003, a wildfire that covered 100,000 acres engulfed the mountains above the West Tunnel.  The fire reached the Waterman Portal—the east entrance—and destroyed construction equipment as workers were evacuated to safety. The project was delayed for 10 days. Two months later—on Christmas Day, 2003—a winter rainstorm deluged the mountains.  A wall of mud and water rushed down Waterman Creek, entered the tunnel, engulfed the tunnel boring machine and swept away many pieces of equipment.   It took four months to repair the damage, and tunneling resumed.

 “I think that because of all the issues that the West Tunnel had—fire, flood, a slow start, difficult ground conditions—there was some thought that we might not be able to finish,” recalled John Bednarski, unit manager V in Corporate Resources, and the Inland Feeder program manager, “so when I saw the TBM break through the mountain, I had feelings of both great pride and great relief.”

Bednarski said strong support from Metropolitan’s board of directors and executive staff made the tunnel completion possible.

Photo by Tom Bleicher

Facing numerous challenges in 2005, the Board reiterated its commitment to the project and directed staff to move forward to get the job done. 

To Metropolitan board Chairman Timothy Brick, the unsung aspect of the project has been its many environmental considerations.

“I’m proud of Metropolitan’s  strong commitment to environmental protection and stewardship,” Brick said.  

 “Metropolitan staff checked numerous mountain-top sites on a weekly basis to monitor streams and groundwater levels to ensure local flows and the groundwater table were not affected."

Brick explained that as additional mitigation, Metropolitan added more than 75 acres in the area to existing holdings of the California Department of Fish and Game and added more than 80 acres to U.S. Forest Service lands in the San Bernardino Mountains.

After the dust settled and the crowds dissipated at Devil Canyon Portal last August, construction workers—the contractor is the joint venture Shea-Kenny—got back to work extricating the TBM and lining the tunnel with sections of 12-foot diameter steel pipe.

Photo by Tom Bleicher

“The next day we actually pushed the whole machine out of the mountain,” Bednarski said, “and took it down to Perris, where it went on the auction block along with the parts we could salvage from the East Tunnel TBM.” 

Meanwhile, tunnel lining continues at a brisk pace, and another celebration was held in April as the last pipe section was delivered and fitted into place.

Photos by Rick Ravenstine