Background Information provided by Fred Quimby: Pristine Merrymeeting Lake outlets into the Merrymeeting River (MMR) which flows through New Durham into Lake Winnipesaukee at Alton Bay. Along this route the river picks up other major tributaries including Coffin Brook and Mill Pond in Alton, New Hampshire. In 2017 this system was known to have a source of phosphorus pollution at the Powder Mill State Fish Hatchery (PMSFH) as well as a number of other potential sources.
Among the problems arising in the watershed are variable milfoil, cyanobacteria blooms, overgrowth of filamentous green algae, high chlorophyll-a concentrations, reduced water transparency, and a growing awareness of anoxia (low oxygen) deep in the water column in waterbodies along the riverine system. To address the water quality issues, the towns of Alton and New Durham have been working to develop a watershed management plan that will identify sources of pollution and result in recommendations to correct them.
Merrymeeting Lake provides the Powder Mill State Fish Hatchery with 7 million gallons of fresh water per day. The water leaving Merrymeeting Lake has an average phosphorus concentration of 5 µg/L (micrograms per liter or parts per billion-ppb). The PMSFH withdraws and discharges a near-constant water load containing phosphorus levels approximately 12 times higher than the outflow concentration from Merrymeeting Lake. The discharge from the facility in summer during low baseflow conditions increases the concentration of phosphorus in the river and downstream waterbodies (leading to algae and cyanobacteria blooms and excessive plant growth)(Ref: Merrymeeting River & Lake Lake Loading Response Model Report, March 2019. FB Environmental & Associates and DK Water Resource Consulting.) Total phosphorus concentrations start at 3.5 ppb in Merrymeeting Lake, and increase to 43 ppb in Marsh Pond, the first waterbody downstream of the fish hatchery.
The PMSFH is registered with the United States Environmental Protection Agency (USEPA) as a concentrated aquatic animal production facility. While the US EPA is charged with limiting the discharge of pollutants from these facilities by issuing NPDES (National Pollutant Discharge Elimination System) discharge permits, until now the USEPA has not imposed any discharge limit on nitrogen, phosphorus or total suspended solids at the PMSFH. The PMSFH permit expired in 2016 and it has been operating under an expired permit ever since this date.
CALL TO ACTION! NH Fish & Game has requested a new discharge permit of 20 ug/L (ppb) from USEPA for the Powder Mill Fish Hatchery in New Durham. The EPA has given October 1 as their estimated time to publish a draft permit in the Federal Register. The draft permit stays in the register for 90 days to allow for public comments. Although the requested discharge permit of 20 ug/L represents a significant improvement over the current amount entering the river; the Cyanobacteria Mitigation Steering Committee has set a water quality goal of 10 ug/L (ppb) for all waterbodies downstream of the PMSFH. Achieving the water quality goal would require a 78% reduction in nutrient loading from the fish hatchery, which the current discharge permit request will not meet.
State Representative Mike Harrington, has been following the PMSFH issue closely. He has been working with Peter Clark at Sen. Shaheen’s Manchester Office (647-7500) on this and was told that Shaheen’s office is keeping the pressure on the EPA to make the Oct 1 date. Rep. Harrington is asking people to keep the pressure on Mr. Clark and Sen. Shaheen, by calling the Manchester office and speaking to Mr. Clark. You can also send a message to the Senator electronically at https://www.shaheen.senate.gov/contact/contact-jeanne.
Rep. Harrington states the following: “The EPA is known to miss dates and we want the Senator’s staff to know how important this draft permit is to so many of us so they will keep the pressure on. Phones calls and messages do make a difference!”
Please help clean up the Merrymeeting River – call Senator Shaheen’s office today!