Introduction   Water Levels   Dam Facts    Reservoir Regulation

INTRODUCTION

Hopkinton and Everett Dams are part of the U.S. Army Corps of Engineer's Hopkinton - Everett Lakes Flood Control Project and are located on two tributaries of the Merrimack River. Hopkinton Dam is on the Contoocook River which enters the Merrimack River at Penacook, New Hampshire and Everett Dam is located on the Piscataquog River which enters the Merrimack at Manchester, New Hampshire. 

The two reservoir system is divided into three storage areas — two in the Contoocook watershed (Hopkinton Lake and Elm Brook Pool) and one on the Piscataquog River (Everett Lake). These storage areas, connected by two canals, act as separate reservoirs during minor floods, and as a single reservoir during moderate or major floods, providing protection to the major industrial, commercial and residential areas along the Merrimack River. These dams are two of the five flood control projects built by the Corps of Engineers in the Merrimack River Basin watershed.

Construction of Hopkinton Dam was started in November 1959 and completed in January 1963. In addition to the protection of the Merrimack River Basin, Hopkinton Lake provides protection to downstream communities along the Contoocook River. The dam is an earth dam consisting of rolled earth fill with rock slope protection. It is approximately 790 feet long and 76 feet high.

Construction of Everett Dam started in November 1959 and was completed in January 1962. As with Hopkinton Dam, it provides protection to the Merrimack River Basin and reduces flood levels in its downstream communities. Everett Dam is an earth dam consisting of rolled earth fill with rock slope protection. It is approximately 2,000 feet long with a maximum height of 115 feet.

At its maximum storage capacity, the Hopkinton - Everett Lakes complex is able to store approximately 51.2 billion gallons of water. 

The Reservoir Regulation Team (RRT), located at the Corps' New England District Headquarters in Concord, MA, is the "nerve center" for all Corps-operated dams in New England. Using radio and satellite communications, RRT constantly monitors river levels and weather conditions and directs the operation of the dams during high flows.