Lake Threats


Cyanobacteria outbreaks and infestations of aquatic invasive species are on the rise in the lakes of NH. SLAM is focused first and foremost on prevention but we are also preparing for such an eventuality with several initiatives:

Mitigation planning – we are developing and maintaining plans for how to deal with an outbreak or infestation.

Mitigation fund – we have established and, with the generous support of our members, begun to build a fund to contribute toward the cost of mitigation.

Coordination with the Town – we are coordinating with the Town of Madison to ensure that an outbreak or infestation is dealt with efficiently.

If you come across a possible Cyanobacteria outbreak please follow the protocol outlined in the below document:

Aquatic Invasive Species (AIS) 

Aquatic Invasive Species (AIS) are non-native plants and animals that have been introduced, accidentally or intentionally, into lakes and rivers. Their introduction threatens the diversity or abundance of native species, the stability of the ecosystem and the enjoyment of the water body. AIS are a major threat to our freshwater ecosystems and a significant management concern because of their ecological and socio-economic costs.

Aquatic invasive plants and animals have become a widespread problem in New Hampshire lakes and ponds. Around 90 state water bodies are plagued with an AIS which pose threats to healthy ecosystems, decrease recreational opportunities, and cause economic impacts in the form of lower property values and loss of tourist income.


The main way invasive species spread from lake to lake is by traveling on boats, trailers, and recreational gear that needs to be properly cleaned, drained, and dried between waterbodies. Large areas of invasive plants in a lake make swimming and boating difficult and dangerous. They are expensive to control and nearly impossible to get rid of