Like in many cities throughout the state, the City of North Liberty has recently become aware of blue-green algae in Beaver Kreek. Although there is not a quick treatment, below is information on what causes these blooms and how to avoid contact. Please note that this does not affect drinking water.
According to the Iowa Department of Natural Resources (DNR), microcystins, sometimes found in ponds, lakes and stream water, are toxins produced by blue-green algae blooms that can be lethal to dogs and cause skin irritation, rashes, and flu-like symptoms in humans. The blue-green algae responsible for releasing these harmful toxins result from an abundance of nitrogen and phosphorus nutrients from grass clippings, fertilizers, septic tanks and other sources that enter ponds and then flow into streams and creeks through runoff. Naturally present algae in the water then feed on these nutrients and quickly multiply. With the perfect combination of warm temperatures and adequate sunlight, algae blooms form across the body of water, allowing for the release of microcystins. Algae and bacteria in water are tested weekly at state and county parks that have beaches. However, North Liberty ponds and lakes are not monitored because none are rated for recreation.
To avoid the danger of microcystins, people and pets should avoid contact with water that is discolored, has scum on the surface, and omits an odor. If contact does occur, wash with soap and water or rinse thoroughly with clean water to remove algae. This is especially important for dogs and other pets because they may lick the algae off their fur to clean themselves. Also, never drink untreated surface water, whether or not algae blooms are present, as it may contain algae toxins or other bacteria or viruses that could cause illness if consumed. Keep in mind that not all pond scum or algae are toxic; however, if you do see it on the water, follow the advice of the Iowa Public Health Department and when in doubt, stay out.
More information on blue-green algae from the Iowa Department of Public Health can be on found online or by calling 515-281-8707. City of North Liberty Stormwater Coordinator Mike Wolfe can also be reached at firstname.lastname@example.org.