With hotter temperatures and increased nutrient runoff in summer months, Harmful Algal Blooms can take over a creek, pond, lake or other slow-moving waterways to cause serious problems. This overgrowth reduces oxygen levels in the water system, which can cause the death of large numbers of fish, shellfish and plants. In addition, the bacteria can be toxic to people, pets, and livestock that enter or drink the water.
How to Spot an Algal Bloom
The blooms are visible as a thick foam or scum on the top of the water — looking much like someone spilled paint across the surface. Colors can vary from bright green and blue-green to white, red or yellow-brown. As bacteria begin to die-off, they can release an unpleasant odor that smells like rotting plants.
While not all blooms are harmful, it is difficult to tell which ones are by simply looking at them. It’s best to avoid waterways that don’t look or smell safe, to not fish in affected areas, and to keep pets away as well — following the mantra “When in Doubt, Stay Out”.
To report an environmental concern in St. Charles County, call the Division of Environmental Health and Protection at 636-949-1800.