NHDES Cyanobacteria Warning for Pleasant Lake
Area near Boat Launch in Elkins
Harmful algal blooms (HABs) have been observed in at least three locations in Pleasant Lake, including Elkins Beach, Elkins Boat Launch and Bunker Road today. HABs are a potentially serious threat to pets and humans upon contact or drinking the water; dogs have died from exposure to, and from drinking water where there are HABs. The toxins can cause dermatitis and in more severe cases liver and brain damage to people.
See the warning below issued by the state DES, and be extra cautious about you or your pets contacting the water in the areas of these algae blooms. Note that these blooms may be more widespread than the limited sampling indicates.
FROM THE NHDES FAQ LINK BELOW
Is it safe to go in the water during a warning or an alert?
NHDES recommends staying out of the water in any part of a waterbody when a cyanobacteria warning is posted, though we do not close waterbodies. This includes swimming, wading and any activity that may result in direct contact with the water. NHDES also recommends against using the water for drinking even when boiled or filtered, dish washing, bathing and other household uses when a warning is in place. Children and pets are particularly vulnerable to cyanotoxins.
If you choose to recreate during a warning, know that you are at risk of exposure to cyanotoxins. If there are enough cyanobacteria in a waterbody to cause a warning, then there is the potential for negative health effects for you, your children and your pets. If you do choose to recreate during a warning, the risk is highest in areas with visible cloudiness, flecks or colored scum, and lower where the water looks clear. Remember that bloom conditions can change rapidly.
If there is an alert, we suggest taking extra care to visually evaluate the water prior to recreating. Stay out if you see something suspicious and report it.
NHDES encourages everyone to assess their risk before swimming or letting children and pets play in the water, regardless of cyanobacteria warning or alert status.
Warning for Pleasant Lake Issued by NHDES today
A cyanobacteria warning has been issued at your lake, please see below for details.
Waterbody: Pleasant Lake, New London
Status: WATCH
Issued: 6/23/25
Bloom Description (photos attached): Green clouds of material
Cyanobacteria Taxa: Dolichospermum
Cyanobacteria Density (cells/mL):
- Elkins Beach: 100,600
- Boat Launch: 238,600
- Bunker Road: 207,400
Notes: Bloom conditions were first observed on 6/19 but quickly dissipated. Bloom conditions reappeared in the morning of 6/23 and samples were collected this afternoon. Samples mixed with pollen.
Please report through the Bloom Report Form if you continue to see bloom conditions.
Please visit the Healthy Swimming Mapper for the most current information about bloom location, status, and severity.
Cyanobacteria reports depict only what an observer sees in the water. The report may reflect a waterbody wide perspective if they boated around the waterbody and made observations, or it could be a single sighting from the shoreline. One sighting does not indicate that a watch or warning is necessary, but it does indicate that those on or around the waterbody should be aware that cyanobacteria have been observed beyond what is natural, and that they should be on the lookout for shifting bloom conditions and report them via the Bloom Report Form.
Watches are issued when samples are evaluated and cyanobacteria are in higher abundance than normal background levels at multiple locations, but that densities are below 70,000 cells/mL or when clear photographic evidence indicates a bloom is occurring.
Warnings are issued when samples are evaluated microscopically, and cell counts exceed 70,000 cells/mL and the bloom is widespread or extends to multiple locations on the waterbody. A warning does not close the waterbody to recreational use. The warning is intended as a precautionary measure to inform the public of the potential health risks associated with cyanobacteria blooms. Please see our updated FAQs for more information.
