U.S., Mexico Sign Pact on Sewage Plant : Border: Agreement calls for building $200-million facility to handle sewage flowing from Tijuana into San Diego. But funding for the project is uncertain.

U.S. and Mexican officials signed a historic pact Monday calling for the construction of a $200-million sewage treatment plant along the border to solve the decades-old problem of raw sewage from Tijuana flowing into San Diego.

The accord, which was approved by authorities from both nations during a meeting in El Paso, is viewed as the culmination of years of often exasperating attempts to resolve the dilemma of how to deal with the huge volume of sewage that flows daily from Tijuana to Southern California.

On a broader scale, the pact also is the latest example of the growing cooperation between authorities from both nations on the environmental problems that plague the nearly 2,000-mile border region--from pesticide runoffs into the Rio Grande to smelter emissions in the Arizona-Sonora area to the dumping of U.S. toxic wastes in Baja California. The presidents of both nations have signed a number of accords in recent years pledging joint efforts to improve the much-abused border environment.

“This is a historic event,” said Francisco Herrera, senior policy adviser to Sen. Pete Wilson (R-Calif.), who has worked on the international sewage issue for years.

The planned project would represent the third binational sewage treatment initiative along the U.S.-Mexico border. A plant now treats wastes from Nogales, Ariz., and Nogales, Mexico, and a planned jointly funded facility would treat Mexican sewage in Nuevo Laredo, Mexico.

The problem of Tijuana’s runaway raw sewage, which has fouled coastline, farms, horse ranches and other land in San Diego for half a century, has inflamed passions on both sides of the border and strained relations between the two nations. The so-called “renegade” flows originate in residential areas of the fast-growing Mexican border city--where pipelines are generally inadequate or non-existent--and go into the Tijuana River Basin, which drains on the U.S. side of the border.

The agreement is the product of often-tortuous negotiations involving officials from Washington and Mexico City, San Diego and Tijuana, Sacramento and Mexicali. Complicating the talks were issues of sovereignty and Mexico’s precarious financial standing and limited ability to invest in such an expensive, high-technology project.

The proposed new plant, which is not expected to be operational until late 1994 or 1995, would exclusively treat Mexican sewage but would be staffed by U.S. and Mexican personnel. Waste effluent, cleansed to U.S. standards, would be discharged into the Pacific via a huge outfall that would extend from the coastline for several miles.

San Diego officials are considering building a separate facility alongside the international plant. The city effluent, while treated separately, would also be dispatched through the ocean outfall.

The proposal still faces a number of major hurdles, notably funding obstacles and an environmental impact statement. The planned site of the plant and outfall is not far from a wetlands habitat protected by U.S. law.

Area officials hope that U.S. authorities will pay for about half of the nearly $200-million project, but only about $14 million has been set aside so far. According to earlier estimates, Mexico is expected to contribute about $41 million--$21 million for pipeline construction in Tijuana and another $20 million for the plant. California and San Diego are expected to provide most of the balance.