UPDATE ON 7-21-23: The City of Coon Rapids received cyanotoxin test results, which were collected on 7-12-23. Results were within the recommended levels established by the MPCA and did not indicate an elevated risk at the time of testing.*
*There is no single approach for evaluating and making decisions regarding the presence and potential threat of harmful algae blooms in bodies of water. Testing surface water for cyanotoxins (toxins produced by blue-green algae) provides the best measure to assess the public health risk from harmful algae blooms (HABs) and inform health-protection decisions. The results reflect conditions at the time the sample was collected; conditions may change quickly, sometimes even before the test results are available.
Crooked Lake remains under a water advisory. Swim at your own risk.
More info. on Crooked Lake water testing.
ORIGINAL POST ON 6-14-23: The City of Coon Rapids has been notified by the Coon Creek Watershed District as of 6-14-23 that a report of a blue-green algae bloom has been detected on Crooked Lake. Blue-green algae blooms are harmful when they produce toxins that can make humans and animals sick.
There is no way to tell if a blue-green algal bloom is toxic just by looking at it. Adults, children and animals should avoid contact with water with blue-green algae. Toxins can persist in the water after a bloom; watch for signs of recent blooms, such as green scum on the shoreline. When in doubt, stay out! If you or your pet go into water where there may be a bloom, wash off with fresh water immediately afterwards.
Though often referred to as algae, blue-green algae are not algae at all, but types of bacteria called cyanobacteria. They are normally present in bodies of water and common in Minnesota. This type of bacteria thrives in warm, nutrient-rich water. When conditions are right, the blue-green algae can grow quickly forming “blooms.” Certain varieties of blue-green algae can produce toxins that are linked to illness in humans and animals.
Signs will be posted at the beach indicating this water advisory for anyone who visits Crooked Lake Park.
For more information about blue-green algae, visit the Minnesota Pollution Control Agency's website.