GrokSurf's San Diego

This past weekend about 30 San Diego County inhabitants and I were guests of the Metropolitan Water District of Southern California (MWD) and the San Diego County Water Authority (SDCWA) for an inspection trip to visit Hoover Dam and Colorado River Aqueduct facilities. Our tour guides were Vincent Mudd (SDCWA Director and representative to MWD’s board), Marty Hundley (MWD Inspection Trip Specialist), and Debbie Espe (SDCWA Senior Water Resources Specialist).

We assembled at SDCWA headquarters at 6:15am Friday where we were seated in the board room directors’ chairs for a brief presentation about the Water Authority, then filed onto a chartered bus to the airport, submitted to the usual TSA indignities and boarding area wait, and boarded our one-hour flight to Las Vegas. There, we rode another chartered bus to Boulder City where box lunches from The Dillinger Food and Drinkery were ready for us, and continued on to Hoover Dam. We ate our lunches in the visitor center auditorium during a speaker presentation and short film about the dam’s history. Then we began our tour.

(your smartphones won’t do these photos justice; you’ll get a much better sense of scale on a large desktop or tablet display and click the pictures for enlargements)

Hoover Dam Visitor Center, awaiting the elevator to the bottom

Generators in the powerplant. There are nine on the Arizona wing, eight on the Nevada side.

Lake Mead’s water level is low so reduced pressure means generators vibrate more and produce less power. Our guide told us a new generator designed to maintain efficiency with less water pressure is being tested and if successful, all will be replaced.

View at the bottom of the dam from the powerplant on the Arizona side.

From the base of the dam, the power plants and the new Mike O’Callaghan – Pat Tillman Memorial Bridge (Hoover Dam Bypass) which allows traffic on U.S. 93 to cross directly into Arizona without having to wait in a long line to drive over the dam.

Back on our bus, we backtracked a little to drive over the bypass bridge and continued southeast on U.S. 93 to Kingman, Arizona. There we turned toward the Colorado River on I-40, then SR 95, passing through Lake Havasu City (yes, we saw the London Bridge) and past Parker Dam.

Our next destination was across the Colorado River on the California side of Parker Dam. If we were in personal automobiles we could have gotten there from here quickly by simply driving across the dam, but with post-2001 security measures larger vehicles are no longer permitted to cross the dam so our bus continued further south for another 15 minutes to the town of Parker where there’s a bridge crossing. We stopped briefly at Parker so members of our group could purchase alcoholic beverages to have with dinner if desired (not a covered expense).

Holding back Lake Havasu, Parker Dam is the deepest dam in the world, with 73% of its structural height of 320 feet below the original riverbed because that’s where the bedrock begins. The dam houses four hydroelectric generators.

After our stop we took the bridge over the Colorado River to the California side and wound our way on the hilly, winding road up to MWD’s field headquarters, Gene Village.

In addition to being a field headquarters for MWD employees responsible for supervising and maintaining the Colorado River Aqueduct, Gene Village is the location for a pumphouse that pushes water from the Gene Wash Reservoir 303 feet up the Whipple Mountains and into a tunnel leading to Copper Basin Reservoir where the Colorado River Aqueduct’s 242-mile path across the desert begins. The facility includes a reservoir that serves as a forebay for the pumps (capacity of 6,300 acre-feet (AF)), a small airfield, a helipad, equipment storage and staging areas, homes for resident MWD employees, a dormitory, guest rooms and lodge, a museum, and a dining hall.

A portion of the village with Gene Wash Reservoir and dam in the distance.

Guest rooms and lodge.

The pump house and riveted supply lines carrying the pumped water uphill.

Supply pipes continue uphill. We weren’t able to learn the story behind the star-shaped light string on the housing at the top.

We had a nice dinner at the dining hall. Rib eye steak (or a vegetarian dish), baked potato, steamed veggies, dinner rolls, ice-cream with choice of sweet sprinkles or hot fudge topping, all delicious. After dessert was served, Director Vince invited us to stand and say a few words about ourselves and what we hoped to get from our tour. Afterwards we retired to the lodge for socializing and it was soon bedtime. Wakeup call would be 6am.

(while preparing this report I came across this interesting anecdotal account about women employed at the camp)

The next morning after breakfast we climbed aboard our bus at 7:15am and drove up a dirt road further into the mountains to see Copper Basin Reservoir and dam.

With a capacity of 24,200 AF, Copper Basin is a major flow control point for the Colorado River Aqueduct. Copper Basin was originally a large, deep canyon across which water coming up from Gene Village had to cross in order to flow into the aqueduct canal that began on the other side.

Originally the aqueduct’s designers considered building an inverted siphon system to convey the water some 200 feet down one side of the canyon and up the other side, something that would have been exceedingly difficult accomplish. Instead, the innovation they implemented was to dam the canyon and fill it up with water. Thus, when the water level is high enough, it spills into the outflow facility on the other side and enters the aqueduct canal. This plan, though, meant that all the water below the outflow structure, some 24,000 AF, would be a “dead pool.”

A natural cave at the dock staging area at Copper Basin Reservoir.

Filing onto the watercraft that will ferry us across the reservoir to the dam.

MWD’s Marty Hundley describing the reservoir’s features.

Stepping up from the boat to reach the dam.

Downstream view from the dam.

Reservoir view from the dam.

A single home at the reservoir for use by the resident caretaker. This is in middle of nowhere so that person has to be okay with being alone much of the time in a very silent environment.

Back on the bus, we headed back down to the Colorado River and over to the official beginning of the Colorado River Aqueduct, the Whitsett Pumping Plant at Lake Havasu. The plant pumps river water 291 feet up to the reservoir at Gene Village. We were taken on a tour inside the facility where we got a close look at the control room and pumps.

Main control room

Plant operator discusses the top portion of the pumps.

We had to go downstairs to see the pump shafts.

Mesmerized by the smoothly spinning shaft.

A stainless steel impeller on display.

Exiting the pump house to look at the pipes climbing up the mountain toward Gene Wash Reservoir.

Next, our bus headed west through the desert on SR62 with the aqueduct visible to our right.

Water in the aqueduct flows across the desert for 60 miles by gravity from Copper Basin to Iron Mountain. At Iron Mountain the water is lifted 144 feet and then turns southwest and flows by gravity to the Eagle Mountains. There the water is lifted 438 feet, and then again an additional 440 feet, to an elevation of 1800 feet above sea level. It continues west across the Coachella Valley until the San Jacinto Mountains where it enters a 13-mile long tunnel leading to Lake Matthews. Distribution points then send the water to various MWD member agencies. The San Diego canal begins here as well, delivering water to the San Diego Aqueduct servicing San Diego County. All told, the Colorado River Aqueduct consists of more than 90 miles of tunnels, nearly 55 miles of cut-and-cover conduit, almost 30 miles of siphons, and five pumping stations.

As it crosses the desert, the siphons are needed so that the aqueduct water can briefly go underground at strategic locations so that stormwater flowing down desert washes can pass through the aqueduct without entering it or causing problems. The drainage system is shown in this satellite photo I found in a document on MWD’s website.

See those triangular shapes meeting the aqueduct? Those are long channels/berms constructed to guide stormwater runoff down the washes to those points at the aqueduct. At those points the aqueduct canal goes underground in an inverted siphon so that the storm runoff can pass overhead without causing problems.

After driving for some time, we turned on to an unpaved aqueduct access road to get a closer look at one of the siphons.

Continuing on, we joined I-10 west and continued on that freeway. We made a brief stop at Chiriaco Summit to visit the George S. Patton Memorial Museum. The museum is in middle of what used to be a gigantic desert training center during World War II and the Colorado River Aqueduct runs through much of that land. Some tanks were on display outside the museum.

Back on the bus now, we devoured the sack lunches prepared for us by the staff at Gene Village. Soon we exited I-10 to take SR-62 west through Box Canyon where we observed some dramatic geological formations caused by the convergence of several large faults, including the San Andreas Fault which crosses the aqueduct. Continuing through the Coachella Valley we rejoined I-10 west until we reached SR-79, west of Banning. We turned south there and drove until we reached Hemet and the huge Diamond Valley Lake reservoir.

The reservoir was created by building giant earth dams at both ends of the valley, plus a small saddle dam on the northern side, creating capacity for 800,000 acre-feet of water. We briefly stopped at the reservoir’s viewpoint on the western side. I didn’t get any pictures there this time, but I have pictures of the lake, dam, and facilities in this blog post describing a previous trip to Diamond Valley Lake.

Continuing our journey, we reached I-15 south and drove back to San Diego, where we made one more stop at the San Vicente Dam in Lakeside around 6pm, where SDCWA has been raising the dam to dramatically increase the reservoir’s capacity. They recently completed topping off the dam raise, which was done using a roller-compacted concrete technique.

SDCWA’s Gina Molise describes the dam raise project to our group.

This is a picture of the dam I shot before the dam was raised.

From a similar angle, this is the raised dam. For comparison, note the position of the two concrete “caves” on the right hillside. The spillway remains in the center of the dam.

All that was left to do was drive back to SDCWA headquarters where our cars were waiting for us.

Here’s a picture of our group taken while we were at the Whitsett plant.

I’m the one in the middle wearing the black polo shirt.

SDCWA and MWD conduct several water facilities tour each year. If you are interested in participating in a future tour, please see SDCWA’s tour web page.