SEATTLE, WA (MyBellinghamNow.com) – A years-long tug of war between Skagit County and a major Seattle utility company has come to a close.

King5 reports that Seattle Mayor Katie Wilson signed a relicensing agreement on Tuesday, May 12, to finalize the Skagit Hydroelectric Project.

The $4 billion settlement will allow Seattle City Light to continue operating three dams on the Skagit River for the next 50 years. The dams supply about 20% of Seattle’s electricity.

It follows several years of negotiations that included debate over the project blocking salmon migration, among other concerns.

Under the finalized agreement, Seattle City Light has pledged nearly $980 million to build fish passage at all three dams. It also includes more investments towards environmental restoration projects.