Lake Water Level - A Cyclical Balance

The NH DES Dam Bureau has a big job. According to state law (RSA 482), the Bureau "regulates the repair, reconstruction, maintenance, and operation of existing dams, reviews design plans and issues decisions for the construction, operation, and maintenance of new dams. They are also responsible for regulating the retention and release of water to support uses such as hydropower generation, autumn lake draw-downs to make room for spring runoff, flood flow management, fisheries and water quality protection for both public and private purposes."  On occasion, these various uses can represent somewhat opposing needs.  

Specifically, the Dam Bureau must balance the multiple public and private interests in surface waters among them: boating, fishing, power generation, wastewater plants, aesthetics, irrigation, and water supplies.  In addition to managing water resources, the Dam Bureau oversees the hydroelectric power generation at state-owned dams, expanding the New Hampshire's clean renewable energy initiative. Statewide and locally, they manage lake levels throughout the year. As mentioned above, they lower lakes in the fall time anticipating "winter low" to limit ice damage and allow for dock repairs. The official  low on Lake Sunapee is at 1090.65, which is the maximum drawdown elevation above sea level or 2.5 ft below the summer level. Then in the spring, anticipating snow melt and spring rains, the lake levels come back up to the "summer  high".  Full summer recreation level  is 10.50 on the gage at Sunapee Harbor, which corresponds to an elevation of 1093.15 above sea level.

This year, during March and early April, lake levels are low all over the state, including those at Squam, Winnipesaukie, and Newfound Lakes and our own Lake Sunapee.  The Dam Bureau explains that the reasons the lakes are so low is that less rain occurred in March than was expected and the ground froze this winter to an extended depth, this year around 7 feet deep. Water in the ground usually contributes to the stream and ground flow by now, but has not done so yet this year due to this extraordinary depth of ground freeze.

That said, the Lake Sunapee level is still within the "allowable" lake level change per a longtime agreement for Lake Sunapee between LSPA and the state. As of last week, it was at the "winter level " low. The level is starting to come up and the dam bureau will work to put it where it belongs for June., that is to say, the lake level usually rises from March to June for the summer season.