The pile of red sand left in the reservoir basin at Upper Stillwater Dam that has discolored the water and allegedly damaged a fishery will be capped with a mixture of soil and cement, the Bureau of Reclamation has announced.
The 800,000-cubic-yard pile of sand, deemed unsuitable for making concrete used in the dam construction, was left in the reservoir basin when the project was completed last fall.The sand mixed with water filling the reservoir; then the red-tinged water was diverted into Rock Creek when the spring runoff began filling the reservoir too fast.
The sand pile is the subject of a suit in federal court filed by members of the Uintah-Ouray Indian Reservation that claims the fine, red silt from the pile polluted the creek and destroyed a fishery there.
Federal and state forest and wildlife officials, along with the Indian tribe, are studying the effects of the sand on fish. That study is expected to be completed by this fall.
A contract for the capping project is scheduled to be awarded by Sept. 1, with construction beginning as quickly as possible so it will be finished before freezing temperatures occur.
Even with the capping of the sand, bureau officials say that some discoloration will occur during next spring's runoff because of the shallow sand layers in the reservoir basin and the settling of the dam.
"The system will flush itself out," said bureau spokesman Barry Wirth, promising a marked improvement over the current discoloration. "We're hoping that next year will be the end of the red-water era."