The reopening of Aliso Beach to swimmers is at least three weeks away, according to a report released last week.
That's how long it may take divers to install temporary repairs inside a leaky sewer outfall pipe, the report from the Aliso Water Management Agency indicated. In the meantime, 100,000 gallons of treated sewage will continue to leak offshore, the report said.
The beach was closed after the leaks were discovered on Feb. 26 in an outfall pipe that normally discharges 18 million gallons of treated sewage about 1 1/2 miles from shore. The leaks were about 100 feet from shore in 10 feet of water.
A television camera inserted into the pipe upstream from the leaks revealed five hairline fractures of the pipe and four or five breaks in the pipe's joints.
Engineers estimate that it will take up to two weeks to fabricate stainless steel clamps to be attached by divers inside the pipe to support the fractured sections, according to the report. The divers, who will enter the 48-inch pipe through a manhole cover about 1,000 yards upstream from the leak, will need another week to install the clamps, the report said.
The water agency's board of directors last week budgeted $130,000 to finish the interim pipe repairs and to analyze what it might take to make permanent repairs, said Michael P. Dunbar, an AWMA director.
Although the cause of the leaks has not been determined, it is assumed that they are related to the Feb. 12 storm that flooded Aliso Creek, Dunbar said. An engineering team is currently analyzing the tapes from the television camera, he said.
"We're pretty sure there is a direct cause and relationship between the storm and the fractures," Dunbar said. "We can't guarantee it, but we're more than reasonably sure the storm was the cause. . . . The baffling part is (that) the pipe lies beneath a bed of rock and five feet of sand. We thought it was pretty well protected."
While the temporary repairs will take an estimated three weeks, Dunbar could not predict an exact date when the beach will reopen. The Orange County Health Care Agency "will make that call," he said.
"We have no control over that," he said. "The (Health Care Agency) has indicated it will reopen the beach as soon as the repairs are completed."