Ventura Cancels Tap Water Warning : Health: Officials say Thursday’s alarm was based on a sample that was either mishandled or taken too early in the treatment process.

Ventura officials on Friday repealed their warnings that much of the city’s water supply was contaminated, suggesting that tests for bacteria were botched by human error.

The reversal came less than 24 hours after the city issued a stern public health advisory to boil water for five minutes before drinking and avoid bathing or showering for at least 48 hours.

The water scare set off a run on stores for bottled water, prompted some restaurants to shut their doors, one hospital to briefly suspend surgery and Ventura educators to close schools on Friday for 8,648 students.

“In my professional opinion, I don’t believe any contaminated water got beyond our first customer,” said Ron Calkins, Ventura’s director of public works. “I’m not sure whether it ever was even contaminated when it left the plant.”

Public water suppliers are required by state law to issue health warnings if one sample turns up positive for infectious bacteria. City officials test Ventura’s water supply daily and, indeed, one of the 20 samples taken in the midst of Tuesday’s flooding tested positive for coliform bacteria, which can cause diarrhea or stomach cramps.

City and state officials said they believe that the initial sample was either mishandled or taken too early in the water-treatment system before chlorine could kill the microbes.

But follow-up tests--taken from the tap of the first customer to receive the water after it leaves the plant--showed Friday that the water was safe to drink. Officials initially issued a 48-hour warning because they feared that Friday’s preliminary test results could be inconclusive and would require another day of testing.

“I am quite sure that even if it was bacteria in the water, by the time the water got to the first customer that there was enough contact time with the chlorine that there was no bacteria in that water,” Calkins said.

“What’s important is that the water’s safe and people can resume their normal practices.”

Calkins said he understands the inconvenience created by the city’s actions. But he said it could not be avoided.

“The system is set up to err on the side of caution,” he said. “It would be devastating if we assumed our water supply was OK and then people got sick. I think it would be irresponsible to do it any other way.”

Some residents reacted to the city’s reversal on Friday with confusion, anger and even outright distrust.

“How can they say that when it’s clear that they just issued a 48-hour warning that the water was contaminated?” asked Teresa Parker, a midtown Ventura resident. “There’s no way I’m taking a shower in that water. If you have a little tiny cut in your finger and you get that in there, there’s no telling what could happen.”

Community Memorial Hospital officials, who suspended surgery for 30 minutes Thursday, said the facility would continue to avoid city water until they conducted their own tests for safety.

“I think it’s understandable skepticism,” said administrator Carol Disme.

After the order to boil water was canceled, Ventura school officials also decided to take extra precautions. Janitors were instructed to run all hot water faucets for 15 minutes and flush all toilets twice.

District Supt. Joseph Spirito said bottled water will be available Tuesday when students return to school.

“If it were adults alone, I might be saying, ‘Boy, this is crazy,’ ” he said. “But when it’s kids, I take every precaution because I’m always concerned about their health and safety.”

He said the students who attend the schools that were shut down Friday will not have to make up the missed day. Under the state education code, superintendents have the authority to cancel classes for health reasons without losing money tied to attendance.

The test samples that set off the alarm were gathered on Tuesday, when torrential flows carried large amounts of mud and other debris down the Ventura River and as well as into the city’s water-treatment plant on the riverbank. Levels of bacteria commonly increase during floods.

City water officials took their daily 20 batches of water for testing Tuesday. When the preliminary results came back Wednesday, they showed that one batch was contaminated. Follow-up tests confirmed the bacteria in that batch.

The city’s water department took more samples Thursday, 19 in all, city officials said. Nine were at the water-treatment plant. The others came from the tap at Paul’s Garage in the northern Ventura Avenue area--the first customer the water reaches after leaving the plant.

None showed bacterial contamination. And the state Department of Health gave the city permission to cancel its health advisory to boil water.

John Curphey, a sanitary engineer with the state health department, said the samples that tested positive for bacteria were taken too close to filters in the water system.

The city usually tests the water after it has a chance to sit in a reservoir for 16 to 20 hours, allowing the chlorine ample time to kill any infectious bacteria, city officials said.

But the reservoir is undergoing expansion work this winter and thus out of commission, leaving the city to test the water as it exits the treatment plant, where the chlorine has had only four hours to do its job, officials said.

Curphey said a more accurate test would have taken the samples closer to where the water flows into homes and businesses. That would give the water more time to mix with the chlorine.

“I think if they would have taken the samples in that other location, they would have been all right,” he said.

The city did not have to wait 48 hours before lifting the ban on tap water because new results showed that the level of bacteria was safe and the level of chlorine in the water had increased, Curphey said.

Rob Shipley, a manager of the Ventura Water Treatment Plant, said the water samples could have been contaminated by the lab technician. He noted that bacteria can be carried on people’s hands even after washing with soap and water.

“Even though you can use the best quality assurance you can, you can still get a contaminated sample,” he said. “That’s why we didn’t take any chances.”

Calkins said the city may never know what really happened at the treatment plant on Tuesday. “We could study it forever,” he said, “but you’re never going to be able to re-create what happened three days ago.”

Times staff writers Mack Reed and Julie Fields and correspondent Paul Elias contributed to this story.

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Making Ventura’s Water Drinkable:

Much of Ventura’s water was deemed undrinkable Thursday after two sets of tests detected a bacteria that causes diarrhea and stomach cramps. About 65,000 residents were ordered to boil water before drinking, cooking or bathing. But retesting completed Friday showed no bacteria. Officials lifted the water ban after declaring the original tests in error.

1. Four wells up to 90 feet deep draw water from beneath the Ventura River.

2. The water is piped into a reservoir and injected with chlorine to kill bacteria. Purity samples are taken before the water is chlorinated.

3. In the treatment plant, more chlorine is added. So are polymers and alum to help particles bond and settle.

4. Pipes feed the water into tanks where the chemicals are allowed to work.

5. Sediment, dead bacteria, organic debris and other material sink to the bottom of settling tanks.

6. Treated water flows to 520-gallon filtration tanks, where mineral filters trap remaining material. More chlorine is added.

7. Normally, filtered water is pumped to a second reservoir, where chlorine works on it for several more hours. But that 17-million-gallon reservoir is closed for repairs, so water is now sent directly to exit pipes.

8. As the treated water enters city water mains, it is tested again for bacteria, sediment and foreign matter.

9. From intake to output, treatment takes 16 to 20 hours with the second reservoir. Water now leaves the plant within two to four hours.

SOURCE: Ventura Dept. of Public Works

Researched by MACK REED / Los Angeles Times