Vermont Dam Safety Program

By Bob Finucane

When we think of the summer landscape of Vermont, much of what we see in the mind's eye is water. Rainfall and snowfall formed the landscape. The laughing brooks and leaping waterfalls add variety and excitement to field and forest. Hundreds of lakes and ponds offer opportunities for recreation, habitat for fish and fowl and water for groundwater recharge and wetlands.

Since the first days of settlement, the number of ponds has increased due to dams built to impound water, first for mills and in more recent years for habitat and recreation. The total number of dams in the state exceeds 1,000, ranging in size from the smallest of farm ponds to Harriman Dam in Whitingham on the Deerfield River, which impounds more than 55 billion gallons of water.

The Vermont Department of Environmental Conservation maintains an inventory of 600 dams, each impounding more than 3 million gallons of water. The highest dam in the state is the federal flood control dam at Ball Mountain in Jamaica at 260 feet. The longest dam is Lake Pinneo in Hartford with an embankment more than 6,500 feet long.

The State of Vermont owns more than 90 dams, with most owned by the Department of Fish and Wildlife. The Agency of Transportation and Corrections is a dam owner, as are Castleton and Lyndon State Colleges and the University of Vermont. The state-owned dams include Waterbury Dam, 187 feet high, 2,130 feet long and impounding 28 billion gallons of water. The estimated replacement cost for all of the state's dams is $200 million.

While Vermont has never had a dam catastrophe like the Johnstown Flood, which killed thousands, a number of dam failures have occurred. The Flood of 1927 was aggravated in some places due to dam washouts. The failure of East Pittsford Dam in 1947 damaged 160 homes.

The Legislature passed Vermont's first dam safety law in 1876. Today, large agricultural dams are regulated by the Natural Resources Conservation Districts, about 100 hydroelectric dams are overseen by the Public Service Board, and the remainder are regulated by the Agency of Natural Resources. These regulatory programs consider both the safety and environmental aspects of dam construction, alteration and removal.

Fewer new dams will be constructed in Vermont as good dam sites are becoming rare and environmental objections are gaining recognition. Existing dams are aging, and a large investment will soon be needed for preservation. Existing law, based on mills and mill dams, places the entire responsibility for dam maintenance on the dam owner. In modern times, with the mill gone and the lakeshore lined with homes, the dam owner may no longer have the incentive or resources to maintain the dam. A proposal for the study of dam problems and remedies is pending before the Legislature.

For more information on the State of Vermont's dam safety programs, please contact Bob Finucane (241-3454 or bobf@wasteman.anr.state.vt.us).

Bob Finucane is a dam safety engineer for the Vermont Agency of Natural Resources.