Health Alert: Elevated Levels of E. coli Bacteria at Some Areas of Folsom Lake State Recreation Area

California State Parks is alerting the public that the Central Valley Regional Water Quality Control Board (RWQCB) has identified elevated levels of E. coli bacteria at Willow Creek Day Use Area, Nimbus Flats and Black Miners Bar Day Use Beach within Folsom Lake State Recreation Area. Samples collected in late June indicate higher levels of the bacteria present at near-shore locations. E. coli is a bacterium found in the intestines of warm-blooded animals and serves as an indicator of fecal pollution in the water. While most E. coli strains are harmless and present at low levels in most waterbodies, it is essential to be cautious when concentration levels are elevated.
RWQCB and State Parks are also monitoring for cyanobacteria (formerly known as blue-green algae) and nuisance algae in freshwater and estuarine waterbodies. If these occur at levels that pose a risk to humans, animals and the environment, they are referred to as freshwater harmful algal blooms, also known as HABs.  
Given the elevated E. Coli testing levels at Lake Natoma and the potential for HABs on Folsom Lake, the public is advised to follow these safety tips:

• Do not drink from any waterbody.
• Keep an eye on pets and wash them with clean water after lake or river play. Provide clean drinking water. Dogs are especially susceptible to cyanobacteria because they may intentionally eat algae clumps or drink large amounts of water, exposing them to potentially fatal toxins.
• Avoid swimming with open wounds.
• Shower after going in lakes or rivers.

To reduce your risk of exposure, please refer to the Centers for Disease Control and Prevention’s Healthy Swimming Habits.
Additional E. Coli testing will continue throughout the summer to monitor the water quality.  Weekly test results are available on the SWAMP Recreational Water Quality Monitoring webpage. 

Current advisories regarding Harmful Algal Blooms (cyanobacteria) can be found on the Water Quality Monitoring Council webpage.

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