The Dam
Holyoke built a series of dams, beginning in 1847. Each dam functioned much longer than its predecessor due to advancement in technology.
When the first serious attempt was begun in 1847 to dam the dull width of the mighty Connecticut River, civil engineering was an emerging field in America. The 1,000 foot long, hemlock timber structure took over a year to built, but only hours after the dam was completed, the river's force dislodged and overturned the dam. The local agent telegraphed the Boston investors: "Your old dam has gone to hell by way of Willimansett."
In 1849, les than a year after the first dam failure, some 500 laborers completed a second, and much stronger, ballasted, timber dam. When the gates were closed, the fall of water vibrated nearby houses. But this dam held.
Major repairs were made in the 1870s with a sloped apron built on the downstream side of the dam.
The dam now in service was constructed with great care in the 1890s and opened in January of 1900, replacing the wooden dam. Over 1,000 feet long and 30 feet high, it is filled with cemented stone rubble and faced with granite blocks. Except for repairs to the crest after a flood in the 1930s, the dam has functioned unchanged throughout the 20th century.
