Fish said to need stable Winnipesaukee River level to thrive

After hearing from those who live and cruise on the lakes, the Winnipesaukee River Watershed Advisory Committee this week began hearing from representatives of those whose very lives depend on the level and quality of the water in the chain of lakes joined by the Winnipesaukee River — fish and other aquatic species.

Don Miller, a fisheries biologist with the New Hampshire Fish & Game Department, told the committee that fish are best served by stable levels in the lakes and flows in the river. Frequent fluctuations in water levels, he explained, expose sediment along the shoreline, which becomes susceptible to erosion when stream flows increase and water levels rise. Erosion washes sediments into the water, often carrying contaminants like mercury and phosphorus that impair water quality and cause algae blooms, both of which can have adverse impacts on fish populations. "It's the frequent fluctuations, changes in levels and flows, we are concerned about," Miller said. "Not so much where the level is as how often it changes."

The stretch of the Winnipesaukee River below the Avery Dam, Miller said, is of utmost importance to the ecology of Lake Winnisquam. The river provides spawning grounds for most of the fish species in the lake, including landlocked salmon, large and small mouth bass, rainbow trout, white and yellow perch. Moreover, he said that the smelt in the lake, whose numbers have recovered, depend on on strong flows from the river in March and April to clear their spawning beds.

Miller stressed that because lake trout spawn in a week around Halloween each year in only a foot or foot-and-a-half of water, stable or increasing flows in the Winnipesaukee River in October were especially important. As a native species that is not stocked, he said that the lake trout was a "species of concern." Miller explained that "unless we supply the native species with the proper habitat, we have no control over these fish."

For the past several months the committee has been gathering information from the different — and often competing — interests throughout the watershed in an effort to determine the optimal water levels and downstream flows required to support recreational activities, wildlife habitat and hydro-electric production while preventing property damage from high water and downstream flooding. Increased competition between the various interests within the watershed, exacerbated by unusually high water in the fall of 2005 and spring of 2006, has prompted a review of the operating parameters applied by the Dam Bureau at the New Hampshire Department of Environmental Services, which manages levels and flows in the watershed.