Moore Dam

Moore Dam is a major hydroelectric and flood control structure on the Connecticut River in northern New Hampshire. Owned and operated by NextEra Energy Resources, it impounds the Moore Reservoir, creating a significant body of water that stretches into Vermont. The facility is a key component of the New England power grid, providing renewable energy and managing water flows along the upper Connecticut River.

History

The development was part of a broader mid-20th century initiative to harness the Connecticut River for hydroelectric power. Planning for the project began in the late 1940s by the New England Power Company, following the success of other dams like the Wilder Dam downstream. Construction commenced in 1954, a period of significant post-war infrastructure investment across New England. The dam was completed and began operations in 1956, subsequently becoming an integral part of the regional energy system managed by successors including New England Electric System and later NextEra Energy Resources.

Design and construction

The structure is a large earthfill embankment dam, standing high and stretching across the river valley. Its core design incorporates a central impervious clay core flanked by zones of selected earth and rock fill, a common technique for large dams of the era like the Union Village Dam. The spillway is a gated concrete chute structure capable of handling major flood events. The powerhouse, located at the base of the dam on the New Hampshire shore, houses three Francis turbine generators, with a combined installed capacity of 48 MW. Key construction challenges involved managing the Connecticut River flow during building and sourcing suitable fill material from nearby areas.

Operations and purpose

Primary operations focus on generating hydroelectricity for the New England power grid, with an average annual production of approximately 185 GWh. The facility plays a crucial role in Flood control by regulating reservoir levels, especially during spring snowmelt and major storm events, coordinating with upstream projects like the Comerford Dam. It also provides ancillary services to the grid, including voltage support and quick response during peak demand periods managed by ISO New England. Water releases are carefully managed to balance power generation, downstream flow requirements for ecosystems, and recreational use of the Moore Reservoir and tailwaters.

Environmental impact

The creation of the Moore Reservoir transformed the local ecology, flooding former riverine habitats and creating a large lacustrine environment. This has affected native fish populations, including Atlantic salmon restoration efforts, by creating a barrier to migration, though fish passage facilities were not originally included. Water temperature and flow fluctuations below the dam can impact downstream habitats. The project is subject to regulations by the Federal Energy Regulatory Commission (FERC) and must comply with conditions aimed at protecting water quality and wildlife, often in consultation with agencies like the New Hampshire Department of Environmental Services and the U.S. Fish and Wildlife Service.

See also

* Connecticut River * List of dams in New Hampshire * Hydroelectricity in the United States * NextEra Energy * Comerford Dam

Category:Dams in New Hampshire Category:Buildings and structures in Grafton County, New Hampshire Category:Hydroelectric power plants in New Hampshire