Dam Removal Strategy:
The removal of the Glines Canyon dam will proceed through a series of steps.
- First, water will be diverted through the penstock to lower Lake Mills Reservoir up to 80 feet. This will allow for work to occur at Elwha dam with some level of flood protection provided by the Lake Mills drawdown.
- Once that preliminary work is accomplished at Elwha dam, removal of the upper portion of Glines Canyon dam can occur. At this point, water is flowing over the newly lowered dam crest. The dam will then be notched on alternating sides to create temporary spillways that can be used to further drain the reservoirs.
- Layers of the dam can then be removed as the reservoir is drained through each new notch. This will be done on alternating sides of the dam until the sediments from the upstream delta have eroded downstream and are resting against the dam.
- At this point, the remaining portion of the dam will be blasted and the river channel restored.