Results Are In, and The Water Is Good!

The State of Water Quality in Lake Opechee 2025 - NH DES Annual Report Gives Opechee High Marks

The New Hampshire Department of Environmental Services (NH DES) has issued their Annual Summary on water quality in Lake Opechee. Based on Lake Opechee Preservation Association (LOPA) volunteers sampling the lake for over 4 years, the NH DES has determined that “Opechee Bay has higher (better) water quality compared to the median NH lake and doesn’t exceed any NH water quality standards”. NH DES adds, “Water quality is generally representative of oligotrophic, or high quality conditions, with low levels of phosphorus and algal growth”.

Although Opechee’s water quality scores high, specific challenges remain. According to Steve Benz, LOPA President and retired water resources engineer, “We are fortunate to be in such a strong water quality position for our beloved lake. Past efforts to regulate nutrients and sediment deposited into the lake are paying off. LOPA’s long-standing advocacy for the lake has established a firm commitment to maintaining and improving water quality further into the future.”

Although the water quality report is generally good news, Opechee is not without its threats. Testing at the deep spot in the lake (61 feet!) indicates that there is a possibility of sediment-related nutrient release under certain conditions. Such releases could increase nutrient levels to the point of excess algae and dangerous cyanobacteria blooms.

NH DES recommends that testing be continued annually, and that after sampling a 10-year period, trends can be established for historic nutrient and water quality factors. LOPA volunteers are fully committed to continued water quality sampling under the NH DES Volunteer Lake Assessment Program (VLAP).

You can find the NH DES report in the Information Center page of LOPA’s website, or directly by clicking here.