The staff of the regional water-pollution agency is expected to recommend that the agency impose an immediate building moratorium in northern San Diego if dry-weather sewage flows to the troubled Pump Station 64 exceed 20.5 million gallons a day before the station is expanded.
The agency's staff is concerned that new construction in the area will increase sewage flows to 100% of the station's capacity before it is rebuilt. Agency officials say they have based their proposal on capacity and flow figures submitted by the city.
Currently, dry-weather flows to the Sorrento Valley pump station average 19 million gallons a day (mgd) according to city figures, said David Barker of the California Regional Water Quality Control Board. Because officials estimate wet-weather flows at twice the level of dry season flows, Barker said wet-weather flows at the pump station are 38 mgd.
The plant's capacity is 41 mgd. City officials have predicted a 3 mgd increase due to new construction between now and November, when Pump Station 64 will have been completely rebuilt.
Barker said the 20.5 mgd dry-weather cutoff figure the staff will recommend at the Regional Water Quality Control Board meeting Friday is a conservative figure based in part on the possibility that the pump station expansion might not occur on schedule.
Pump Station 64 has malfunctioned 59 times in the last seven years, dumping millions of gallons of raw sewage into Penasquitos Lagoon. The spills have prompted brief building moratoriums, threats of massive fines and an $8-million program to expand the plant.