Weekly Report & Winni Bloom Watch Map

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Check This Out! Weekly Report & Winni Bloom Watch Map

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Watch Now: The Value of Lake Winnipesaukee

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The map below indicates Cyanobacteria advisories and sightings in the Lake Winnipesaukee watershed.

This map will be updated on a weekly basis. For more information about Cyanobacteria, to report a harmful algal bloom or to log pictures of your sightings (bloomWatch) please use the links below:

Report a Bloom

Bloom Watch

 Common Cyanobacteria of New England

 What are Algal Toxins?

The green circles represent confirmed sightings while red triangles represent advisories issued and  yellow triangles represent alerts by the New Hampshire Department of Environmental Services (DES).

Advisories Removed: 

Sighting Locations: Please note that this map is meant to be used as an informational tool with approximate locations of cyanobacteria sightings. Click the points on the map for additional details. Surface blooms can rapidly change and accumulate in various locations around a waterbody.

      • Pine Island (Week of 8/9 – 8/13)
      • The Broads (Week of 8/9 – 8/13)
      • Bear Island (Week of 8/9 – 8/13)
      • Wolfeboro Bay (Week of 8/9 – 8/13)
      • Winter Harbor (Week of 8/9 – 8/20)
      • Green’s Basin (Week of 8/16-8/20)
      • Governor’s Island (Week of 8/23- 8/27)
      • Chase Island (Week of 8/23- 8/27)
      • Glendale Docks (Week of 8/23- 8/27)
      • Chestnut Cove (Week of 8/23- 8/27)
      • 19 Mile Bay (Week of 9/6- 9/10)
      • Ash Cove (Week of 9/20- 9/24)
      • Saunders Bay (Week of 9/20-9/24)
      • Greene’s Basin (Week of 11/8-11/12)