August 22, 2024
The U.S. Forest Service will need to decide if the replacement dam at Eightmile Lake complies with the Wilderness Act.
Before the Icicle Peshastin Irrigation District can start construction of the dam, it will need approval, probably in the form of a special use permit, from the Forest Service. The irrigation district could apply for such a permit anytime, but not much is likely to happen during this fire season. After that, the Forest Service will apparently undertake an environmental review process before reaching a decision. Because Eightmile Lake is within the Alpine Lakes Wilderness, the replacement dam must comply with the Wilderness Act and related forest management directives.
The Wilderness Act allows a new water project within a wilderness, but only if the U.S. President approves it after determining that it "will better serve the interests of the United States and the people thereof than will its denial." Otherwise the Act forbids structures or installations within a wilderness, subject to "existing private rights."
No one seems to dispute the irrigation district's grandfathered right to operate, maintain, or even rebuild the dam its predecessor erected in 1929. So the question will be whether the proposed replacement dam changes that right.
Courts have strictly construed the term "existing private rights" in wilderness areas and on other public lands subject to the same or similar language. Thus, the owner of an existing dock within a national seashore could not relocate the dock after sediment made its current location too shallow. In another case, to protect endangered fish the Forest Service could restrict how much of an irrigation district's existing water right it could divert across national forest land. In the same vein, the owner of a mining claim established before the area became a wilderness could still obtain a patent for subsurface rights, but not for surface rights, because its claim was now within a wilderness. In short, courts have frowned on relocation or expansion of existing private rights, especially within a wilderness.
At Eightmile Lake, the Forest Service will have to decide how these principles apply. How would the replacement dam change the irrigation district's existing rights?
The original elevation of Eightmile Lake is uncertain. Years ago, a slide had occurred near the outlet. As at many mountain lakes, logs and debris had also collected, creating something of a natural dam. The irrigation district's predecessor first cut a channel at the outlet, installed a pipe, and then completed its dam in 1929. According to reports, the dam was never built to its intended height due to leakage around the slide area. Whatever it may have been before, the full lake level became 4,671 feet. The dam and lake stood at that height until 1990, when flooding and erosion knocked off the top four feet of the dam. That dropped the full lake level to 4,667 feet, where it has been ever since.
The replacement dam design approved by Washington's Department of Ecology would restore the lake level to 4,671 feet – the elevation maintained for the dam's first 61 years. That would flood 4.8 acres that have been above the waterline since the dam lost its top in 1990.
The Forest Service will need to decide which dam height represents an "existing" private right. On the one hand, the dam was functioning at its higher level when Congress created the Alpine Lakes Wilderness in 1976, and it stayed at that historic level for another 14 years. One could say it was the height that the Alpine Lakes Wilderness inherited. On the other hand, the dam has functioned at its lower height for the past 34 years -- since the 1990 damage to it -- allowing a natural forest to regrow along nearly five acres of shoreline that were previously inundated. During most of those 34 years, the irrigation district apparently took no steps to restore the dam to its earlier height.
In deciding the extent of the existing private right here, the height of the replacement dam might or might not be a subject of debate. But the same cannot be said for the level of lake drawdown.
At no time in the past has the irrigation district withdrawn water that dropped the lake level below 4,640 feet. The proposed new dam, however, is designed with a lower outlet pipe so that water withdrawal could lower the lake another four feet, creating an additional two and a half acres of exposed, muddy shore. This bigger "bathtub ring" would represent a change, and one that visitors would notice. If the irrigation district resorted to pumping, the lake level could drop even lower.
The plan for a lower outlet pipe will allow the irrigation district to lower Eightmile Lake more than it has ever been before. It remains to be seen if a reasonable argument can be made to reconcile this with the Wilderness Act's protection of "existing" private rights.
These wilderness issues were not the focus of Ecology's environmental review. Now they likely will become front and center.