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New Hampshire Department of Environmental Services
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FOR IMMEDIATE RELEASE
DATE: August 7, 2019
CONTACT: Amanda McQuaid (603) 271-0698 (O), 848-8094 (C)
des.nh.gov
twitter.com/NHDES

State Issues Cyanobacteria Advisory for Franklin-Pierce Lake in Hillsborough, New Hampshire

Concord, NH - A cyanobacteria bloom has been observed on Franklin-Pierce Lake in Hillsborough, NH. A surface scum accumulating along the shoreline appeared blue-green, with thin ribbons along the Manahan Park Beach. Samples collected on 8/6 from the beach area exceeded the State threshold of 70,000 cells/ml of cyanobacteria. Samples contained Anabaena/Dolichospermum taxa and were estimated as 377,500 cells/ml. However, on 8/7 the bloom appeared to have mostly dissipated. There was still some evidence of cyanobacteria at this location as of 8/7, with green stains in the sand and few particles in the water. Cell concentrations have likely reduced significantly and follow-up sampling with occur this week. As a result, the New Hampshire Department of Environmental Services (NHDES) has issued a cyanobacteria advisory for those who swim at the beach and use the waterbody for recreation. It is also advised to look out for accumulations in other areas of the lake and avoid contact. Please continue to monitor your individual shoreline for changing conditions.

NHDES monitors public beaches and public waters of the state for cyanobacteria. Once a cyanobacteria advisory has been issued, NHDES returns to affected waterbodies weekly until the cyanobacteria standards are again met. NHDES advises lake users to avoid contact with the water in areas experiencing elevated cyanobacteria cell conditions. NHDES also advises pet owners to keep their pets out of any waters that have a cyanobacteria bloom.

This advisory is not based on a toxin evaluation and is intended as a precautionary measure for short term exposure. Cyanobacteria are natural components of water bodies worldwide, though blooms and surface scums may form when excess nutrients are available to the water. Some cyanobacteria produce toxins that are stored within the cells and 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, tingling, numbness, nausea, vomiting, seizures and diarrhea. Chronic effects may include liver and central nervous system damage. Be cautious of lake water that has a surface scum, changes colors, or appears to have green streaks or blue-green flecks aggregating along the shore.

The cyanobacteria advisory went into effect on August 7, 2019 and will remain in effect until NHDES confirms that cell concentrations of the bloom have subsided.

Visit the NHDES Beach Program website for photos and more information about cyanobacteria at www.des.nh.gov/organization/divisions/water/wmb/beaches/index.htm
Updates on advisories and warnings may be obtained at www4.des.state.nh.us/WaterShed_BeachMaps/WaterShed_BeachMaps.aspx
Follow the Beaches twitter feed:
twitter.com/NHDES_Beaches

If you notice anything resembling cyanobacteria, please refrain from wading, swimming, or drinking the water. Keep all pets out of the water and contact NHDES immediately. Please call NHDES to report a cyanobacteria bloom at (603) 848-8094.




NH Department of Environmental Services | 29 Hazen Drive | PO Box 95 | Concord, NH 03302-0095
(603) 271-3503 | TDD Access: Relay NH 1-800-735-2964 | Hours: M-F, 8am-4pm

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