Repairs to Ruptured Sewage Pipe Completed

As the first in a series of showers rolled into Ventura County, repair teams finally mended a storm-ravaged Thousand Oaks sewer main Thursday--but the flow of raw sewage into a hillside creek will not stop until the line is reopened late today.

By then, an estimated 63 million gallons of sewage will have dumped into the Arroyo Conejo on its way to the Pacific Ocean 15 miles downstream.

If the line holds under pressure this afternoon, it will have been 10 1/2 days since torrential rains undercut the 30-inch-wide concrete pipeline--snapping it in three places and closing nearly 30 miles of beaches in two counties because of potential health hazards.

“This takes an enormous load off the shoulders of a lot of people, if it holds,” city Public Works Director Don Nelson said. “This has been an absolutely miserable time for this city.”

The ruptured sewer main--which usually carries 60% of city sewage--was repaired Thursday when workers reconnected the concrete line with a 60-foot length of steel, cinched the steel and concrete together with huge collars and sealed the seams with tons of concrete.

An initial repair last Friday washed out when a punishing new storm undercut the line before the concrete seals hardened. This time, workers are waiting for the seals to harden and will slowly reapply pressure to the pipe before rerouting millions of gallons through the line. Exhausted workers can now only cross their fingers and hope that smaller storms today, Saturday and Monday will not undo the repairs of this week.

“I think we just need to appreciate the amount of work and effort the staff and construction workers put into what is admittedly an environmental catastrophe,” said City Councilman Andy Fox, who on Thursday called on the city to fully cooperate with agencies investigating the spill.

Already, Thousand Oaks is working under an order from state water officials to fix the line--which has ruptured three times since 1989--and make sure it never breaks again.

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In a hand-delivered letter Tuesday, the Regional Water Quality Control Board in Los Angeles directed Thousand Oaks officials to submit three reports over the next 10 days detailing the extent of the problem, steps taken to fix it and what must be done to offset contamination of creeks, ground water and the ocean.

By March 15, the city must submit a plan to fix the problem for good. The city faces fines of $5,000 a day for each violation of state water law. Officials indicated Thursday the city’s defense may be that the sewer break is an unavoidable act of nature.

“It is not the time to get caught up in the emotional hoopla of fines or blame: Our main focus is on the repair,” City Atty. Mark Sellers said. “But El Nino is not something that happens very often. My backyard even flooded out and that hasn’t happened before. So I know this was an unusual rain event.”

Thousand Oaks received about 12 inches of rain in the first 10 days of February--70% of its normal rainfall for the entire year.

Nonetheless, the regional water board’s abatement order notes that two breaks in the Thousand Oaks sewer main released 13 million gallons of sewage into the Arroyo Conejo in 1989 and 1995. Replacement of the line was set for the last two summers, but never occurred. And the water board order suggests the city is to blame.

“Had those repairs been made, this spill may not have occurred,” the order said.

Blame aside, city officials plan to fully line a 6,000-foot section of the ruptured line, and install a backup line next to it by summer, at a cost of $4.5 million. A second length will be reinforced next summer for $4 million, officials said.

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But for now, city officials say they can only hope for gentle rains. And weather seems to be on Thousand Oaks’ side this time.

Forecasters say the showers to come probably will not be severe enough to cause further damage--and do not compare with violent inch-an-hour downpours of the last two weeks.

Each of the three storms over the holiday weekend could drop one-half to 1 inch of rain on Ventura County, said meteorologist Gary Ryan of the National Weather Service’s office in Oxnard.

“It’s a whole different thing this time. These storms are moving so fast--they’re riding the jet stream at 150 mph--that they just don’t have time to drop the heavy amounts we had earlier this month,” Ryan said.

“The storm that’s going to be here Monday is out in the vicinity of Japan right now,” Ryan said. “It’s a close cousin of the one that’s dropping rain on Nagano [site of the Winter Olympics] right now. That’s how fast it’s moving. You almost couldn’t get here that fast on United Airlines.”

Ryan does not expect relief over the next month.

“We’re going to be seeing above-normal precipitation through March,” he said. “It’s going to be one of the wettest years of this century. We’re already way above our normal for the entire season.”

Meanwhile Thursday, operators of the overflowing Lake Piru Reservoir warned residents and workers along Piru Creek to be cautious this weekend because of the new storms.

Water began to spill over the dam at Lake Piru on Wednesday, only the ninth time since 1960 that the lake has overflowed.

Lake Piru was drained lower than normal last summer in anticipation of this El Nino winter, officials said.

“We pulled it way down,” said Dana Wisehart, senior manager of the United Water Conservation District. “And that has protected the Piru Creek from any flooding. But now we’re anticipating those creek flows are going to increase.”

The county’s largest reservoir, Casitas Lake, began overflowing its spillway last week, for only the eighth time since it was built in 1960 and first filled in 1978.

(BEGIN TEXT OF INFOBOX / INFOGRAPHIC)

Seasonal County Rainfall

Here are rainfall figures for the past year in inches. Oct. 1 is the start of the official rain year. Also shown are the average rainfall amounts for the entire year and the record rainfall. With the El Nino weather pattern now in the Pacific Ocean, many weather experts are predicting record rainfall throughout California. The last El Nino, in 1983, produced many of the record rainfalls.

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Normal Rainfall Percent Average Record rainfall since of normal annual annual Location to date Oct. 1 rainfall rainfall rainfall Camarillo 8.03 21.19 264% 13.30 33.43 Casitas Dam 13.96 32.62 234% 23.38 51.13 Casitas Rec. 13.92 32.03 230% 23.26 * Center Fillmore 11.31 24.99 221% 18.77 42.30 Matilija 15.76 33.28 211% 26.94 70.04 Dam Moorpark 8.71 21.06 242% 14.75 32.48 Ojai 12.51 27.61 221% 21.52 48.60 Upper Ojai 13.47 28.91 215% 23.67 56.58 Oxnard 8.59 23.48 273% 14.59 38.17 Piru 10.16 20.60 203% 17.35 40.36 Port 8.44 22.23 263% 14.06 32.99 Hueneme Santa Paula 10.49 23.35 223% 17.54 38.03 Simi Valley 8.37 21.64 259% 14.49 35.06 Thousand Oaks 9.03 20.21 224% 15.38 32.75 Ventura Govt. 9.50 26.83 282% 16.09 39.95 Center

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* Maximum rainfall amounts not available for all locations

Source: Ventura County Flood Control District