Ruptured Sewage Pipe in Ocean Repaired After 63 Days; Cost to Exceed $15 Million

After discharging up to 180 million gallons of partially treated waste each day for more than two months, the rupture in the city’s sewage outfall pipeline was repaired last weekend.

The cost of 63 days of repairs was estimated to be $11 million. Another $4.5 million is expected to be spent on covering the pipe with “armor rock” for stability and protection, City Manager Jack McGory said.

The cause of the break, discovered Feb. 2 by the Coast Guard, is still under investigation.

For the past seven weeks, teams of workers traded 12-hour shifts, seven days a week, with interruptions only for inclement weather. The 70 divers, pipe layers, tugboat skippers, helicopter pilots, engineers, technicians and tradesmen were weary but cheered by the completion.

“There were a few high-fives,” when they finished putting the pipe back together, said Marc Stearns, repair project manager.

Mayor Maureen O’Connor gave pipeline supervisors three bottles of champagne for a celebration after the 5 a.m. reopening of the sewage line Saturday. Earlier, O’Connor and McGory inspected operations on the repair barge above the damaged section of pipe, about three-quarters of a mile from shore. From there, they observed the coupling of the final segment.

The next step, O’Connor said, is to reopen beaches that have been quarantined because of the spill.

“We’ll do our best to . . . make sure all the quarantine signs are down for spring break,” O’Connor said, referring to this Friday when local schools go on vacation.

Coliform bacteria counts at stretches of beach near the Point Loma outfall and other outlets for urban runoff still tested more than 1,000 bacteria per 100 milliliters of water--the safe standard used by the county. During the worst periods, county health authorities quarantined 19 1/2 miles of San Diego coastline, with readings reaching 60,000 near the treatment center. Cumulatively, about 11 billion gallons of partially treated sewage spewed from the break.

Lingering high counts in some areas are the result of street runoff from recent storms and another spill from a sewage pumping station in Tijuana, said Gary Stephany, deputy director of the county’s Department of Health Services.

A preliminary report on the outfall rupture is expected by the first week of May, McGory said.

Theories on the cause of the mishap vary. They include the settling of the ocean floor combined with heavy wave action.

Another theory is that human error played a role. Five workers at the Point Loma treatment plant told The Times last month that a mistake in handling trapped air in the outfall pipe created a “water hammer.” The five workers said the force of a huge air bubble rushing through the pipe may have shaken several segments from their foundation.

A third theory is based on deep gouges found on more than 200 feet of pipe, city officials said. The scrapings have fed speculation that an anchor or a heavy object being towed by a ship may have bumped the pipe and ruptured it.

The city has been named in several claims connected to the sewage spill, including one by 38 fishermen who say that the rupture has damaged the ecosystem in the waters off Point Loma.