Lake Wildwood: E. coli source still unclear, Nevada County to hire consultant to continue investigation; non-swim advisory in effect |

Lake Wildwood: E. coli source still unclear, Nevada County to hire consultant to continue investigation; non-swim advisory in effect

Lake Wildwood's Community Center Pool Beach was closed in July due to elevated levels of E. coli found in the water. An investigation this summer found that 18 cases of E. coli-related illness reported in Nevada County were directly linked to Lake Wildwood.
Elias Funez/ |

Now that cooler weather has moved in and the summer recreation season has become a distant memory, the Nevada County Environmental Health Department has stopped its twice-weekly water testing routine at Lake Wildwood.

But the investigation into the source of elevated levels of E. coli in the lake continues.

According to Amy Irani, director of the Environmental Health Department, E. coli bacteria typically die off in cooler weather which, the department found, was the case at Lake Wildwood when county employees did their last round of testing in October.

But the investigation into elevated bacteria levels that caused an outbreak of E. coli-related illnesses this summer is still ongoing, Irani said. A no-swim advisory remains in effect at the lake.

The county, Irani said, is soliciting an outside agency with freshwater testing expertise to take the reins on the Wildwood investigation.

She’s unsure who that agency might be, but said she hopes it will take into account the testing done so far by county staff and make recommendations on how to proceed. The county would then devise a plan for the Lake Wildwood Association, detailing ongoing testing guidelines.

As far as the source of the contamination, Irani said, the Environmental Health Department hasn’t yet identified “a smoking gun.”

Possible sources include wildlife, the natural environment or man-made causes, she said.

“We have everything on a dartboard, but there’s nothing we’ve been able to pinpoint,” Irani said. “That’s why we’re looking for an external expert to come in and give some guidance moving forward.”

low water level

Bob Mariani, executive director of the Lake Wildwood Association, said the lake’s water level is lower than normal right now.

That’s part of an annual process, he said, that allows the association to clean out silt deposited into the lake from winter rainstorms. It also gives Wildwood homeowners a chance to make any necessary repairs to their docks.

The association, which routinely tests the lake’s water during the recreation season, has also stopped taking samples now that winter is approaching.

Mariani said he’s looking forward to hearing from the consultant the county plans to hire, who he hopes will provide more insight into this summer’s E. coli outbreak.

To contact Staff Writer Matthew Pera, email or call 530-477-4231.

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