A plan to demolish four dams along the lower Klamath River in Oregon and California cleared its last federal bureaucratic hurdle Thursday, when U.S. regulators voted to greenlight what is set to be the country’s largest dam removal project.

The Federal Energy Regulatory Commission (FERC) voted Thursday to approve the plan, which would restore hundreds of miles of the Klamath River and clear the waterway for salmon.

“Some people might ask in this time of great need for zero emissions, ‘Why are we removing the dams?’ First, we have to understand this doesn’t happen every day … a lot of these projects were licensed a number of years back when there wasn’t as much focus on environmental issues. Some of these projects have a significant impact on the environment and a significant impact on fish,” said FERC Chairman Richard Glick.

The FERC approval lets the electric power company PacifiCorp surrender its licenses for the four dams, and the project can begin once Oregon, California and the Klamath River Renewal Corporation sign off on the surrender. 

The project, lauded by Native American groups and environmentalists, would clear hundreds of miles of river in southern Oregon and northern California. 

The first dam is expected to come down sometime next year, with a goal to complete the rest of the project by 2024. 

The Associated Press contributed to this report.