Y2K Test Sends Sewage Flowing Into Park, Street


Raising concerns about the city’s ability to handle the year 2000 computer problem, a test of the emergency system at a sanitation plant went awry Wednesday night, spilling about 4 million gallons of untreated sewage into part of the Sepulveda Dam Recreation Area before officials could stop it.

Officials at the San Fernando Valley plant had been testing a backup electricity system in anticipation of a possible Y2K power outage when they learned from a park ranger shortly after midnight that sewage was gushing from a maintenance hole in the 2,100-acre recreation area.

City and commercial crews largely succeeded in corralling the stream of sewage flowing into the recreation area and kept it away from the Los Angeles River, a nearby golf course and a popular Japanese garden where two weddings are scheduled for this weekend.


Workers toiled through the night with high-powered vacuum cleaners to remove the waste from park grass. Street sweepers with water hoses cleared raw sewage from the street. As a precaution, 10 acres of Woodley Avenue Park, a grassy picnic area, were closed for the weekend.

But health officials say the spill posed little danger to the public. The bacteria from any remaining sewage will be burned off by the sun’s ultraviolet rays, experts say.

“If there is skin contact, generally the worst that could happen is just a rash,” said Jack Petralia, director of the county Bureau of Environmental Protection. “We brought some specialists out who said the best thing we can do is let the sun burn off all of the bacteria,” said Steve Soboroff, president of the city Parks Commission.

Meanwhile, the odor “wasn’t pleasant, that’s for sure,” said Caroline Piligra, who lives in Van Nuys, across the freeway from the treatment plant. The smell, she said, lingered into Thursday night.

The spill occurred when a gate controlling the transfer of sewage from a large pipeline was mistakenly closed during the test, backing up sewage to street level for about two hours. Officials traced the malfunction to a programmer’s error made in 1985.

Judy Wilson, director of the city Sanitation Bureau, said she has ordered a review of the computer programs for all gates in the city sewer system. City officials said the problem can be fixed quickly and should not present a threat when computer clocks strike 12 a.m. Jan. 1.

“I have every confidence that once we figure out what the logic problem is with this gate, we can fix it very easily,” Wilson said. “It just underscores the importance of doing real-time testing rather than tabletop exercises.”

Mayor Richard Riordan also gave assurances that the problems will be addressed. Los Angeles has been testing Y2K readiness for two years and has experienced some minor glitches.

“I have instructed the bureau to thoroughly investigate the circumstances so that when they conduct future tests we can avoid repeating similar occurrences,” Riordan said. “Overall, the city is confident that its critical systems will be ready and operational for Y2K rollover, and we are continuing our contingency plans.”

The Y2K problem stems from the use of two digits to represent years in computer programming. In 2000, computer systems could become confused over the date “00,” which could be read as either 1900 or 2000, resulting in malfunctions or miscalculations.

The sewage spill, which the city estimates will cost less than $100,000 to clean up, has worried some environmental groups.

Mark Gold of Heal the Bay, a Santa Monica environmental group, said he has talked with the city about fears over trouble at the massive Hyperion sewage treatment plant. A malfunction there could dump sewage into Santa Monica Bay.

Gold said the spill at the much-smaller Donald C. Tillman Water Reclamation Plant, which treats about 65 million gallons of sewage a day, is a sign that the city’s preparations may not be well planned.

Officials at Tillman had not placed any monitors at the surface during the testing, nor was there any electronic warning that the gate malfunctioned.

“So you’re doing this test at midnight and you don’t have people on the surface?” Gold said. “That doesn’t sound like good planning to me. There definitely is a lot of concern, because of the complex, technical nature of these plants. A lot can go wrong.”

Curtis Paxton, the plant’s assistant manager, said no one was assigned to monitor the park, checking for spills, because “we hadn’t had any trouble before.”

John Norton, the official in charge of enforcement and compliance issues for the State Water Resources Control Board, said the Tillman spill was the first Y2K failure among waste-water plants in California. State water officials have the power to fine local agencies and are monitoring Y2K compliance by sewage treatment plants in hopes of avoiding spills next year.

“That’s one of the things that the state [Environmental Protection Agency] and the state water board are concerned about,” Norton said. “We want them to test for Y2K, but also to be very cautious about doing so. We don’t want to create problems; we want to solve them.”

Word of the sewage spill spread quickly through the community of expert consultants on the Y2K computer glitch.

As private companies and government agencies test their computers for potential problems, experts say, some are getting more than they bargained for. At the Peach Bottom nuclear power plant in Pennsylvania, for instance, computers crashed for seven hours in February during Y2K testing. In Perth, Australia, large loads of chemicals were mistakenly dumped into the water during a Y2K test.

“The good news is that they’re actually out there looking at all the angles, and they’re actually finding problems prior to Y2K,” said Rich Cowles, a consultant for the state of California as well as private corporations. “The bad news is that it shows problems exist.”

Kevin Corcoran, the project manager for Los Angeles’ year 2000 program, said 134 of the city’s 147 major computer systems are in compliance and the rest will meet that goal by Sept. 30. Corcoran said those systems do not include smaller computer networks.

The spill at Tillman began during testing for an electric power outage--one of the possible troubles that could result from the Y2K bug.

At 9:40 p.m. city Department of Water and Power crews shut off electricity to the plant, and operators turned on emergency diesel-powered generators, Paxton said.

The master computer went off for a few minutes during the transition from city electricity to generator power. When the computer came back, it sent a “fail/close” message between 9:45 p.m. and 10 p.m. to an underground gate that controls the flow of raw sewage.

The mistaken closure caused raw sewage to back up in an 8-foot-diameter pipe called the Additional Valley Outfall Relief Sewer. The computer controlling the gate did not notify plant workers that it had closed.

The city park ranger notified plant operators, who went to the park, found the backup and at 12:15 a.m. redirected the flow, Paxton said. Plant officials then ordered the cleanup.

Paxton blamed the mishap on a glitch in the computer program that had been in the system since the plant opened in 1985. It had never been detected during previous tests or power failures.

By coincidence, Woodley Avenue Park had been among the sites the city considered for an official millennium celebration for 100,000 people on New Year’s Eve.

Times staff writers Agnes Diggs, Irene Garcia, Annette Kondo, Hilary MacGregor and Martha L. Willman contributed to this story.


San Fernando Valley Sewage Spill

Four million gallons of raw sewage spilled into Woodley Avenue Park in the Sepulveda Basin Recreation Area late Wednesday night after a computer malfunction at the adjacent Donald C. Tillman Water Reclamation Plant. Officials at the plant had been conducting tests of a backup power system in preparation for the year 2000 computer problem when a gate to a major sewer pipe closed without warning because of a programming error.