What’s in your water?

Drinking water is safe despite high coliform level

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Posted 8/17/18

August brings unprecedented contamination in Fremont Lake.

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What’s in your water?

Drinking water is safe despite high coliform level

Posted

PINEDALE – Recent routine tests of Pinedale’s drinking water source, Fremont Lake, revealed something never before experienced – high amounts of fecal coliform in the lake.

If the source isn’t found and the levels don’t decrease, the town could face a $16-million upgrade for a filtration system.

Only months ago, attendees of the Wyoming Association of Municipality toured Pinedale’s water treatment plant and Fremont Lake, which boasts the only water system in Wyoming that meets stringent federal standards from an open source so water filtration is not required. New test results threaten that status.

Currently, water from Fremont Lake is gravity-fed to the Pinedale water treatment facility, where it is treated with chlorine and an ultraviolet system. The water is not filtered to remove larger particles. However, the chlorine and ultraviolet treatments kill the coliform.

In order to be certified, the town must test the water in Fremont Lake and regularly submit samples. The town must also test water after it’s treated and at random locations as it leaves faucets.

The Environmental Protection Agency requires routine samples from an open source, like Fremont Lake, to have fewer than 20 colony forming units of fecal coliform per sample. Fecal coliform is a bacteria found in the intestines of warm-blooded animals. Tests are also done for giardia and Cryptosporidium parasites. A water source may not exceed the standards any more than five times in a six-month period or it may no longer be certified as a non-filtration system.

Fremont Lake’s pristine waters have always met those criteria.

Spencer Hartman, water and sewer supervisor for Pinedale, reported during the Aug. 13 town council meeting that changed in August.

On July 25, tests showed the water tested positive for 3 FCU for fecal coliform; on July. 31, that had jumped to 229.

In an email to Pinedale’s staff and council members, Mayor Matt Murdock called that “strike one of 5.” By Thursday, Aug. 2, that number had grown to 618 CFU – strike 2 of 5. Only one day later on Aug. 2, the number hit 716 CFU. That number will not count against the town, because samples were taken for the entire length of the lake in an attempt to find the source. However, later samples taken after that, showed declines, still count as strikes. By Aug. 9 the number had dropped to 170.

The lake continues to be clear of giardia and Cryptosporidium parasites.

Murdock updated council members in an email on Aug. 3, saying Hartman is in contact with EPA. The emails were requested by the Pinedale Roundup after hearing about the contamination.

“They are fully aware of our situation and are not concerned with our potable, treated water within the town,” Murdock said.

Hartman scheduled the use of an underwater camera with TipTop Search and Rescue to determine if a dead animal in the water near the intake could be causing the contamination. No obvious source was found.

He said because the bacteria was widespread throughout the lake, it is unlikely a single source, such as a leaking septic tank or a boat emptying its holding tank. He said it could be coming from sediment in the lake.

“It’s a fascinating mystery,” Hartman said. He has been trying to find other open water systems without filtration, but there are only a handful in the United States with Pinedale being the only one in Wyoming.

By email, Murdock requested the council’s consensus to authorize expenditures to send samples to a specialized lab that could determine what species of warm-blooded animal was producing the contamination and to expedite the results. The council followed up at its regular meeting, approving that $2,150 expenditure. Subsequent tests are showing a reduction but to date there are four strikes.

The lab doing tests agreed to wait until Saturday of this week, the last day possible, in an attempt to avoid a fifth strike.

A $16 million fix

Josh Wilson, director of public works for Pinedale, explained that he had researched the costs of installing a filtration system in 2007 when the EPA set the standards for a non-filtration system.

Because land would need to be purchased and a large holding tank would be needed, the costs 11 years ago were $16 million.

“That’s when we went for the UV system,” Wilson said. That’s an expense the town wants to avoid.

Ironically, a new filtration system would not stop the fecal coliform contamination.

“They’re so small, they would go through the filter,” Hartman said. “The filter stops the larger colonies of giardia and Cryptosporidium parasites and sediment.”

Chlorine and UV treatment are keeping the tap water safe, he said.

Recreation

EPA standards set the FCU level for a recreation facility like Fremont Lake at 1,000 FCU before additional requirements are needed, so you can swim in the lake, but not drink the untreated water. “We’re in contact with the U.S. Forest Service,” Murdock said. “Once we’re through we want to form a task force with EPA and the Forest Service.”