AUGUSTA, Maine — A backhoe took a bite out of the Edwards Dam 10 years ago, releasing the waters of the Kennebec River that had been held back for more than a century and a half.

At a recent anniversary ceremony, conservationists and sporting enthusiasts hailed the July 1, 1999, removal of the longtime landmark as a major step toward returning one of Maine’s largest rivers to its natural state and restoring fisheries.

“Edwards was not the first dam removal,” said Stephanie Lindloff, senior director of American Rivers’ river restoration program. “But it was the first one that prompted a more focused discussion about removal of dams, especially those with safety issues and that had outlived their usefulness.”

Numbers provided by American Rivers suggest the Maine dam’s removal set the stage for more than 430 others across the country — more than three times the 130 taken down between 1990 and 1998.

As federal dam licenses have come up for renewal, owners and regulators have been more likely to question whether dams with relatively little power output are worth keeping.

Last year, more than 60 dams in 14 states were removed, according to American Rivers’ count.