Water samples collected by the Maryland Department of the Environment (MDE) and Department of Natural Resources (DNR) in the northern main stem and adjacent tributaries of the Chesapeake Bay have tested positive for high levels of the blue-green algae, Microcystis.
In hot weather and especially in still water with high levels of nutrients, blue-green algae can grow and accumulate rapidly, causing a "bloom." Blue-green algae blooms of this nature occur periodically in tidal-fresh and low salinity portions of the Chesapeake Bay and its tributaries.
Current surveys show that the Microcystis blooms have been observed on the Northern Bay and its tributaries, including the Sassafras, Bohemia and Elk Rivers in Cecil County.
Although there have been no reported cases of human illness, The Maryland Department of Health and Mental Hygiene reminds people to take common precautions to reduce the risk of illness or discomfort related to Microcystis:
- Do not swim in areas where blue-green algae bloom is evident.
- Do not drink water from any area with appearance of blue-green algae bloom.
- If contact is made with problem water, simply wash off with fresh water. Skin irritations may occur, in some cases, after prolonged contact. If irritations persist, contact physician or local health provider.
- Keep pets and livestock away from the bloom area. Microcystis blooms may contain a toxin that could be harmful to pets and livestock.
This growth may periodically use up oxygen, causing fish to suffocate. Affected water may look like someone has spilled a blue-green to yellow-green paint on the surface of the water. To report an algal bloom, call DNR at 410-260-8630.
DNR crews will continue sampling the algae bloom in the Kent and Cecil County areas over the coming weeks.
Information on Microcystis can be found at the DNR Web site: www.dnr.state.md.us/bay/hab/microcystis.html.
Posted: 8-23-2001
