Sewage spill continues to pollute Tijuana River for third straight day

A sewage spill that federal officials said started Monday night south of the border continues to flood the Tijuana River with millions of gallons of raw effluent.

A ruptured collector pipe in southeast Tijuana is leaking roughly 7 million gallons a day of sewage into the river, according to the U.S. section of the International Boundary and Water Commission.

While beach closures for Coronado and the Silver Strand had been lifted as of Wednesday, the shoreline in Imperial Beach remains closed to swimmers because of sewage contamination, according to the San Diego County Department of Environmental Health.

The rupture of the Colector Poniente was discovered after soil collapsed above a pipe, causing several sinkholes at an auto junkyard, according to the boundary and water commission.

The collector had undergone millions of dollars’ worth of upgrades during the last year, but the section of pipe that burst had yet to be addressed as it was deeply buried under at least one structure, according to federal officials.

Following the discovery, a government agency that operates Tijuana’s sewer and water delivery systems diverted the flows to a storm-water collector that drains into the Tijuana River.

U.S. officials have estimated the ongoing spill at about 7 million gallons a day.

The boundary and water commission said utility officials in Baja California would attempt to divert the flows Wednesday from the Tijuana River back into the city’s wastewater treatment system.

joshua.smith@sduniontribune.com

Smith writes for the San Diego Union-Tribune.