Workers will be repairing the Tin Cup Dam, a 1906 structure in the Selway-Bitterroot Wilderness west of Darby, Montana.
Crews will start the project August 1st and will repair the embankment and modify the dam's spillway.
The plan went through an Environmental Assessment last year, which set out the rules in which the work can be conducted. A helicopter will be used for about 9 days to haul heavy equipment and lessen the impact on the trail leading to the dam. All other equipment will be packed in horses or mules.
The dam is 7 miles inside the wilderness boundary and is 25 feet high and over 400 feet long. Failure of the dam could result in loss of life and property, according to forest officials. The project is slated to be completed within 90 days. For information, call the Darby Ranger District at (406) 821-3913.