State Parks urges caution at Willow Creek, Nimbus Flats and Black Miners Bar after recent water samples show elevated bacteria levels
California State Parks is advising the public to use caution at three Folsom Lake State Recreation Area sites after elevated levels of E. coli bacteria were identified in recent water quality testing.
According to California State Parks, the Central Valley Regional Water Quality Control Board identified elevated levels of E. coli bacteria at Willow Creek Day Use Area, Nimbus Flats and Black Miners Bar Day Use Beach. Samples collected in late June showed higher levels of the bacteria at near-shore locations.
E. coli is a bacterium found in the intestines of warm-blooded animals and is commonly used as an indicator of fecal pollution in water. While most strains of E. coli are harmless and are often present at low levels in natural waterbodies, elevated concentrations can increase the risk of illness for people who come into contact with affected water.
The advisory comes as summer recreation activity continues across Folsom Lake State Recreation Area, one of the region’s busiest outdoor destinations for swimming, boating, paddling, fishing and shoreline recreation. State Parks said additional E. coli testing will continue throughout the summer to monitor water quality conditions.
The Central Valley Regional Water Quality Control Board and State Parks are also monitoring for cyanobacteria, formerly known as blue-green algae, as well as nuisance algae in freshwater and estuarine waterbodies. When cyanobacteria or algae occur at levels that pose a risk to humans, animals and the environment, they are known as freshwater harmful algal blooms, or HABs.
Given the elevated E. coli testing levels at Lake Natoma and the potential for harmful algal blooms on Folsom Lake, State Parks is advising visitors to take precautions while recreating in or near the water.
Visitors should not drink water from any lake, river or other waterbody. Pets should be closely watched near the water and washed with clean water after lake or river play. Pet owners should also provide clean drinking water for their animals. Dogs are especially susceptible to cyanobacteria because they may intentionally eat algae clumps or drink large amounts of water, which can expose them to potentially fatal toxins.
State Parks is also advising the public to avoid swimming with open wounds and to shower after going into lakes or rivers. Visitors are encouraged to follow healthy swimming practices recommended by the Centers for Disease Control and Prevention to reduce the risk of exposure.
Weekly E. coli test results will continue to be posted through the SWAMP Recreational Water Quality Monitoring webpage. Current advisories regarding harmful algal blooms and cyanobacteria are available through the Water Quality Monitoring Council webpage.
The advisory does not close Folsom Lake State Recreation Area, but it does urge visitors to be aware of current water quality concerns and take appropriate precautions before entering the water, especially at near-shore areas where elevated bacteria levels were detected.
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