Holyoke Dam
The Holyoke Dam, also referred to as the Hadley Falls Dam, or Hadley Falls Station is a granite dam built in tandem with the Holyoke Canal System at Hadley Falls on the Connecticut River, between Holyoke and South Hadley, Massachusetts. The water differential created by the dam produced mechanical hydropower for industrial uses in Holyoke, and later hydroelectric power.
| Holyoke Dam | |
|---|---|
Holyoke Dam during spring thaw | |
Location of Holyoke Dam in the western Massachusetts, USA | |
| Country | United States |
| Location | Hampden County and Hampshire County Massachusetts |
| Coordinates | 42°12′49″N 72°36′06″W |
| Purpose | Power, regulation, industrial |
| Status | Operational |
| Construction began | 1895 |
| Opening date | 1900 |
| Construction cost | ≈$1,000,000 (1900) |
| Built by | Fruin-Baurbrick H. S. Hopkins, St. Louis |
| Owner(s) | Holyoke Gas & Electric |
| Operator(s) | Holyoke Gas & Electric |
| Dam and spillways | |
| Type of dam | Granite gravity |
| Impounds | Connecticut River |
| Height (foundation) | 30 ft (33.5 ft while rubber bladder is inflated) |
| Length | 1,020 ft (310 m) |
| Elevation at crest | 94.6 ft (28.8 m) |
The current dam is the third structure to be built across the Great Falls at South Hadley. The dam, along with the Canal System and its Testing Flume, is recognized by the American Society of Mechanical Engineers as a Historic Mechanical Engineering Landmark for its use by Clemens Herschel in the development of the Venturi meter, the first means of measuring large-scale flows, and the McCormick-Holyoke Turbine by John B. McCormick, also known as the Hercules Turbine, which doubled the efficiency of turbines to more than 80% in its time.