Cynaobacteria blooms are increasing in many New Hampshire lakes and our lake is no exception. Last year we had at least two such blooms that were verified by NH DES, one almost impacting the busy July 4th week. In 2023, Lake Kanasatka had a bloom that lasted 121 days, effectively shutting down lake activities for most of the summer and into the fall. Cyanobacteria can cause serious health issues and even deaths in rare cases. They are caused by several factors, most notably increasing phosphorous levels and rising average lake temperatures due to climate change. Phosphorous enters the lake primarily from water runoff from the land. This phosphorus loading is increased by actions such as fertilizing lawns, cutting down shoreland vegetation, using impervious surface materials, and not controlling erosion.
The PLIA is concerned about the increasing phosphorous levels in the lake and is working with DES, state and town officials to apply for grants to update our watershed plan. Our most recent plan was developed in 2008 and there have been many changes to the lake since then. The PLIA applied for a so-called “604B” grant last fall but we were not successful. This spring we intend to apply for a Clean Water State Revolving Fund grant from NH DES. If we do get the grant, we plan to engage a contractor to update our watershed plan. The plan will cost around $70K and will take at least a year to produce. With a new plan in hand, we will be able to request additional grants to perform mitigation projects to reduce incoming phosphorous and, we hope, lessen the potential for future cyanobacteria blooms.
All lake resident can also help in this effort by reducing property runoff, eliminating the use of fertilizers, making sure their septic tanks are functioning well, and protecting shoreline vegetation.