On Monday, September 21, 2026 through Friday, October 2, 2026, Pennichuck will be performing a series of fire flow tests throughout the Litchfield, Londonderry, and Nashua Core Systems. These fire flow tests are being performed due to system improvements. Technicians will be flushing hydrants to dispel naturally occurring sediment and air from the main. Residents who experience discolored water should run their cold water for approximately 10 minutes. If the issue persists, please call Customer Service at 800-553-5191. Residents who have any questions regarding the fire flow test schedule, please call 603-202-0448. Thank you for your patience as we work to protect the quality of your water.

Existing BMPs

Over the years, Pennichuck has installed 89 best management practices (BMPs) within its watershed to capture and treat stormwater before it enters waterways. This greatly reduces the contamination of source waters by pollutants present on roadways and disturbed land, which can be carried by stormwater as it flows over land. Below are some examples of these BMPs, as well as a comprehensive inventory of each BMP in the Pennichuck watershed with a corresponding map. These BMPs can also be viewed on the Interactive Watershed Map.