INCHELIUM — The Colville Indian Reservation borders Lake Roosevelt to the south and east, and outside the reservation, tribal allotments dot its shoreline.
The tribal government operates businesses and maintains parks along its banks.
Many tribal members live and play on this 150-mile stretch of the Columbia River. They use sweat lodges on its beaches, and gather plants for medicines and baskets. They and hunt and fish there.
But as the years pile up with no answers about what, exactly,…