PORTLAND, Ore. (AP) — For the first time in its history, the U.S. Army Corps of Engineers will have to disclose the amount of pollutants its dams are sending into waterways in a groundbreaking legal settlement that could have broad implications for the Corps’ hundreds of dams nationwide.

The Corps announced in a settlement Monday that it will immediately notify the conservation group that filed the lawsuit of any oil spills among its eight dams on the Columbia and Snake rivers in Oregon and Washington.