Since 1997, Maine has led the nation on removing dams and restoring rivers and their watersheds. That year, the federal government for the first time required the removal of a dam whose ecological harm outweighed its hydropower benefits: the Edwards Dam on the Kennebec River in Augusta.

Federal policy was established at the urging of numerous local and national environmental organizations. Since Edwards, dam removal has moved from being unthinkable to becoming a compelling tool for the restoration of our nations’ rivers. As just one measure of the robust recovery from removing the Edwards Dam, the number of alewives in the lower Kennebec increased from 78,000 in 1999 to 5.5 million recently, improving the health of the Gulf of Maine as well as the river.

Over 1,200 dams across the country and about 45 dams in Maine have been removed in the last 25 years. Maine’s 45 include dams in rivers and towns as varied as: Augusta (Kennebec), Winslow (Sebasticook), Old Town and Veazie (Penobscot), Alna and Whitefield (Sheepscot), Penobscot and Hancock (Bagaduce), Vassalboro (China Lake Outlet Stream), Westbrook (Presumpscot), West Winterport (Penobscot), Brewer and Orrington (Sedgeunkedunk). I could go on, but you get the idea.

The most widely recognized project since Edwards was conducted by the Penobscot River Restoration Trust, a partnership of six Maine environmental organizations, the Penobscot Tribe, and various agencies of the federal government. At a cost of over $60 million, the Veazie and Old Town dams were removed, and a naturalized fish passage was constructed around the dam at Howland. This project examined the entire Penobscot watershed, rather than just one dam at a time. Over 1,000 miles of river were opened for fish migration. It has become a model for river restoration around the world, with teams from China and elsewhere coming to learn.

While the dams on the Penobscot and the Kennebec were power generators, the vast majority of the removals were relics. They no longer served their original economic purpose, were expensive to maintain, prevented the passage of migratory fish, and in some cases worsened the flood risks in their watersheds. These projects were supported by local land trusts for each watershed, as well as national and state-wide groups such as The Nature Conservancy, Maine Coast Heritage Trust, Atlantic Salmon Federation, Natural Resources Council of Maine, Trout Unlimited, Maine Audubon, American Rivers, Maine Rivers, Downeast Salmon Federation, and more.

Maine generates about 30 per cent of its power from about 170 hydropower dams. Some should be removed (like the lower four on the Kennebec River which block salmon passage up the Sandy River watershed, perhaps the best salmon spawning habitat on the East Coast) and some (like those further up the Kennebec) should not. Every unique dam situation must be examined.

That is why the river restoration plan for the Megunticook River contemplates leaving the East and West Dams, which maintain the water level of Megunticook Lake, as well as Seabright Dam, which swells the river between Molyneaux Road and Shirttail Point. Naturalized fish passages could be built around these dams, allowing the water levels to be maintained while providing access for migratory fish.

The remaining dams, including the Montgomery Dam at the head of the harbor, serve no practical function. They also block the passage of migratory fish, increase the risk of flooding throughout the length of the river and cannot be bypassed with a naturalized fishway.

Since I have been involved in both dam removal and dam preservation, my experience in dam preservation in Freedom, Maine might be instructive in its contrast to the Montgomery Dam in Camden.

In Freedom, the original mill is still there (in Camden there is no mill). Sandy Stream in Freedom has never seen any migratory alewives or Atlantic salmon. In fact, the two dams on Sandy Stream separate the native fish below the dam from the species introduced above the dam. Freedom’s mill and dam are 100 river miles from the bay at the far reaches of the Kennebec watershed (versus at the mouth of the river in Camden where the dam affects the whole watershed). The Freedom millpond has a natural shoreline on all sides (versus an unattractive impoundment in Camden that is mostly hidden under buildings and roads), and the Freedom dam allows a hydroelectric turbine to generate power for the equivalent of eight to 10 homes.

A future Restore Megunticook column will discuss river restoration in more detail than space allows today.

Tony Grassi has served as Chairman of both American Rivers and the international board of The Nature Conservancy, one of the world’s leading environmental organizations. He lives in Camden.