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Location: Augusta, Maine, USA
Completion Date: 1837
Reservoir Capacity: 740 million cubic feet
Type: Embankment (timber crib)
Purpose: Hydroelectric power
Misc: removed 1999
Materials: Timber, rock, concrete
Engineer(s): Kennebec Dam Company
On the morning of July 1, 1999, thousands of people lined the banks of the Kennebec River in Augusta, Maine, to watch workers punch a hole in the Edwards Dam. Water began trickling through the hole, and within minutes, a raging torrent gushed past the 915-foot-long, 20-foot-tall wall of rock, log, and concrete. Crowds cheered as the Kennebec River flowed freely past the Edwards Dam out to the Atlantic Ocean for the first time in more than 160 years.
The Edwards Dam was the first hydroelectric dam in the country removed by the federal government for environmental reasons. It was built in 1837 to supply power to mills along the river's banks. But by the mid-1990s, the old dam was generating only 3.5 megawatts of electricity in 1990 -- an amount equal to .1 percent of Maine's annual energy usage.
Even before the dam was built, environmentalists argued that a dam on the Kennebec would block salmon, shad, herring, and other fish from reaching their spawning grounds upstream. They were right. Soon after the dam was built, these fish all but disappeared from the river.
For the first time in history, the federal government decided that the damage the Edwards Dam caused far outweighed its benefits. The dam was removed against the owner's will at a cost of $7.3 million.Here's how this dam stacks up against some of the biggest dams in the world.
(reservoir capacity, in cubic feet)