With little fanfare, the City of San Diego has completed its $23-million effort to repair the Sorrento Valley pumping station that has malfunctioned 59 times since 1979, spilling millions of gallons of raw sewage into Los Penasquitos Lagoon.
The installation last week of a $3-million force main leading away from the facility is the last repair work the city was required by state water pollution regulators to make to Pump Station 64, said Yvonne Rehg, the city's water department spokeswoman.
With the pipe's installation, she said, the city on Jan. 29 also lifted a moratorium that prevented the hookup of nearly 2,200 homes, condominiums and apartments into sewers leading to Pump Station 64. The station services some of San Diego's fastest-growing neighborhoods, including Scripps Ranch, Mira Mesa, Rancho Penasquitos, Sorrento Valley and North City West.
"We hope this means an end to sewage spills into Penasquitos Lagoon," Rehg said.
The pump station "has been a major problem and I think we are all breathing a lot easier now that it's finished," she said. "Hopefully, the citizens of San Diego will be enjoying Torrey Pines beach a lot more this summer."
Lapsed Into Disrepair
Pump Station 64 came to symbolize the city's failure to tend to routine maintenance of the sewer system. Although it was a crucial link in the city's sewage system, it had been allowed to lapse into disrepair. At one point, it was not expanded and became a virtual bottleneck for effluent from the burgeoning northern neighborhoods.
The result has been a legacy of spills in adjacent Los Penasquitos Lagoon--a history that one official from the state's Regional Water Quality Control Board termed "abysmal."
In 1986, the board clamped down on the city and ordered the $23-million construction program. Even then, there were mishaps at the station.
On Thanksgiving in 1986, a city employee mistakenly shut down the pump and sent 1.5 million gallons of raw sewage into the lagoon.
The following March, a power surge at the station cracked the force main and sent 20.8 million gallons into the lagoon again.
The incidents--as well as a missed deadline in the repair scheduled--prompted the water quality control board to impose almost $214,000 in fines on the city, Rehg said.
Repairs to the facility were extensive. When it came time to replace four 200-horsepower pumps with four 500-horsepower pumps, engineers determined that the old pump station floor would not be strong enough to hold the heavier machinery. The city then built a new pump station to hold the larger pumps--construction that was unforeseen, Rehg said.
The new pumps expanded the station's capacity from 41 million gallons to 53 million gallons a day.
Other major improvements at the station include a backup power source for the pumps, and an 84-inch underground pipe designed to catch any sewage spill of up to 350,000 gallons.
The final repair was installation of a second force main, 1.9 miles of 42-inch pipe. With the new pipe, the station's capacity has increased to 62 million gallons of sewage a day, Rehg said. Installation of the force main was finished Jan. 29, more than five months before the June 15 deadline set by the water quality board.
The installation also lifts a city-imposed ban on sewer hookups for new development in the Pump Station 64 area. On hold were connections for 1,099 single-family houses, 1,088 apartments and condominiums, and 123 commercial buildings, Rehg said. The connection ban did not preclude developers from building the houses and businesses, only hooking into the sewers, she said.
Rehg said there's one more project slated for the pump station--a $1.1 million repair to the first force main, a job that has not been required by the state. When that repair is completed, the station's capacity will expand to 73 million gallons a day, she said.