The U.S. Bureau of Reclamation and Grand Coulee Dam School District disagree on the impact a bureau project will have on local schools.

The USBR is planning a 10-year project to update three generators, named G19-21, in the Third Powerhouse starting in 2023, similar to the ongoing project of updating G22-24 that started in 2010, and is estimated to cost $100 million.

The USBR’s Environmental...