Andy Adams Reservoir Algal Bloom Monitoring 2020

Update November 2, 2020

The Warning Advisory for Andy Adams Reservoir has been removed as a result of the end of the sampling and monitoring recreation season.

The Utah Division of Water Quality’s water recreation season runs from May 1 through October 31. At this time, no further monitoring or sampling for harmful algal blooms or waterborne pathogens at priority water bodies will be conducted until May 2021.

This does not mean that the potential for harmful algal blooms or waterborne pathogens has ceased. Please remain aware while recreating in or near water bodies and for information on how to keep yourself, your family, and your pets safe, please visit:

• Protect Yourself During Harmful Algal Blooms
• Protect Yourself: Waterborne Pathogens

Update August 21, 2020

Davis County Health Department has issued a Warning Advisory for Andy Adams Reservoir due to observations of an increase in magnitude of a harmful algal bloom along the west side of the reservoir. Davis County Health Department is posting signs at access points along the reservoir.

Update August 19, 2020

Andy Adams Reservoir was sampled 8/13/2020 and had a concentration (62K cells/ml) of toxigenic cyanobacteria (Microcystis) which is below the recommended Warning advisory level (100K cells/ml). However, because elevated levels of toxigenic cyanobacteria have been quantified, we are highlighting this result as a Health Watch.

A Health Watch is not a formal recreational advisory, but rather an indicator that a bloom may exist or become more severe. Indicators can include visual reports, but in this case observations were quantified in a laboratory. Toxin results are pending.