The Border

The California Coastal Commission on Wednesday approved the 12,300-foot “Big Pipe” expected to one day connect a proposed sewage treatment plant on the U.S.-Mexico border with a 6-mile ocean outfall planned by the city of San Diego.

The $37-million pipeline now needs only the approval of the U.S. Army Corps of Engineers before the city can begin soliciting bids on contracts, said Pete Silva, assistant deputy director of special projects for San Diego’s Water Utilities Department.

The 12-foot-diameter, underground pipeline is expected to route sewage from a joint Mexico-U.S. treatment facility to be opened in 1995 on the border by the International Boundary and Water Commission. That system is seen as the solution to the 12 million to 13 million gallons of raw sewage that now cascades across the border each day, fouling beaches and damaging a sensitive waterfowl habitat.

The pipe, originally envisioned as part of a system that would have sent the sewage back across the border for treatment in Mexico, will link the border treatment plant with the city’s proposed sewage outfall. That outfall would begin about two miles inland and extend 18,000 feet into the ocean, Silva said.

Under the terms of Wednesday’s decision, the city of San Diego will have to seek an amendment from the commission if it follows through with plans to build a South Bay sewage-treatment plant adjacent to the border facility.