Horseshoe Pond Cyanobacteria Warning Lifted

The state has lifted a cyanobacteria warning on Merrimack's Horseshoe Pond that was issued on July 17. The cell concentration has tested below a level of public health concern, according to a press release from the Department of Environmental Services sent Friday afternoon.

Samples collected Friday, August 2, from the beaches and boat launch had minimal amounts of cyanobacteria. However, once a bloom has been seen in a lake, that lake is more likely to have future blooms. Please continue to monitor your individual shoreline for changing conditions and avoid any large amounts of bluish-green growth in the water. 

More from the DES press release: 

DES routinely monitors public beaches and public waters of the state for cyanobacteria. Once a cyanobacteria warning has been issued, DES returns to affected waterbodies on a weekly basis until the cyanobacteria bloom is not evident. Cyanobacteria are natural components of water bodies worldwide, but blooms and surface scums may form when excess phosphorus is available to the water.

Some cyanobacteria produce toxins that are stored within the cells but released upon cell death. Toxins can cause both acute and chronic health effects that range in severity. Acute health effects include irritation of skin and mucous membranes, nausea, vomiting, and diarrhea. Chronic effects include liver and central nervous system damage. 

Visit the DES Beach Program website for photos and more information about cyanobacteria.

Updates on advisories and warnings may be obtained on the DES website.

Follow the Beaches Twitter feed.

If you notice anything resembling cyanobacteria, please refrain from wading, swimming, or drinking the water.  Keep all pets out of the water and contact DES immediately. Please call DES to report a cyanobacteria bloom at (603) 419-9229