Speak Up for the Alpine Lakes Wilderness: Eightmile Lake Dam Replacement Update

A proposal to remove and replace an aging dam at Eightmile Lake could have negative impacts on wilderness and recreation in the Alpine Lakes Wilderness. We share the latest updates on this project and the final opportunity to share feedback and shape the final outcome.
The Mountaineers The Mountaineers
May 19, 2023
Speak Up for the Alpine Lakes Wilderness: Eightmile Lake Dam Replacement Update
Lead image of Eightmile Lake and Eightmile Dam. Photo courtesy of The Wilderness Society.

In January 2021, we shared how the effort to replace the dam at Eightmile Lake in the Alpine Lakes Wilderness could bring negative impacts to the Wilderness area and the world-class outdoor recreation opportunities it provides.

Last month, the Washington State Department of Ecology (Ecology) announced a draft Environmental Impact Statement (EIS) outlining potential strategies to remove and rebuild the dam. While this plan addresses some of our previous concerns about appropriate actions in protected Wilderness and impacts on recreation, questions are still left unanswered.

Ecology recently held three public hearings and is seeking public comment on the draft EIS through June 5, 2023. We’re calling on Mountaineers to take action once again for one of our region’s iconic landscapes. Read on for what’s in the plan, and share your comments to make sure that your perspective is heard during the final stages of the planning process.

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The Enchantments is home to pristine alpine lakes and towering peaks - a prime destination for hiking, backpacking, scrambling, backcountry skiing, and climbing. The Enchantments is one of the most visited areas in the Alpine Lakes Wilderness and its overnight permits are highly coveted by recreationists in the Pacific Northwest and beyond. Eightmile Lake and the Eightmile Dam is located within the Enchantments Permit Zone. The trail to Eightmile Lake also provides access to Eightmile Mountain, Lake Caroline, and Cashmere Mountain.

The Icicle and Peshastin Irrigation Districts (IPID) owns and operates a 90-year-old dam on Eightmile Lake, located in the Alpine Lakes Wilderness. As a result of flood damage and erosion caused by the impacts of the 2017 Jack Fire, a state of emergency was declared and IPID made emergency repairs to the dam. The Department of Ecology’s Dam Safety Office designated the Eightmile Lake Dam as a “high hazard” for failure and a threat to lives and property downstream. IPID is required to repair the dam to current safety requirements or remove the dam.

Ecology is in the process of performing an environmental review to assess the best courses of action to remove and replace the Eightmile Dam. The goal of this project is to restore storage capacity and repair the dam in accordance with safety regulations, while minimizing impact on the environment.

Unpacking the Draft Environmental Impact Statement

The draft EIS examines the probable, significant, and adverse impacts resulting from the rebuild and restoration of the dam. It also analyzes how impacts can be reduced or eliminated through mitigation. As the dam owner, the Icicle and Peshastin Irrigation Districts have worked with Ecology to identify the environmental impacts of three action alternatives for how to repair and replace the dam, and a “no action” alternative, which would maintain the status quo.

  • Alternative 1: A new dam with a narrow spillway with gates.
  • Alternative 2: A new dam with a wide spillway without gates.
  • Alternative 3: A new dam with a narrow spillway without gates.
  • No Action Alternative: Operate the current dam with no changes.

Addressing Concerns

Land managers incorporated what they heard during the 2021 comment period when developing the four proposed alternatives. Among other changes, the building of new roads and overland vehicle transport during construction has been removed from consideration. This was one of our main concerns with the previous plan and we’re glad to see it will not move forward.

What would construction look like?

Construction of a new dam would affect the wilderness character of the area by drawing down the lake level, clearing some vegetation, and creating construction-related noise. Construction is anticipated to span one summer season, lasting for an estimated four to five months.

Construction materials will need to be brought into the Eightmile Dam area by helicopter. Land managers will decide between utilizing a heavy-lift helicopter, requiring fewer trips and a larger staging area for materials and one that would require more trips but leave lesser on-the-ground impact and cause less noise disturbance. While this level of helicopter use is unprecedented in Wilderness and will result in noise impacts to the area, we’re glad to see that no roads will be built as a part of the construction. Following construction, all disturbed areas would be restored and replanted with native vegetation, and all construction materials removed.

Impacts on Wilderness

Here at The Mountaineers, we believe designated wilderness is a core tool in protecting the outdoor experience, and that honoring this designation is key to protecting our public lands. Wilderness areas include some of our most beloved areas for hiking, climbing, scrambling, and backcountry skiing. The designation protects the wildlife habitat and ecosystems that makes our outdoor adventures so special.

We are encouraged to see that roadbuilding and vehicle transport are no longer on the table, but operation of all of the action alternatives would affect wilderness character by continuing to manipulate the water level and creating a more “developed” appearance of the dam. We’re also closely watching for any proposals to reconstruct other “high hazard” dams at lakes much further into the Alpine Lakes Wilderness, including the dam at Colchuck Lake. Reconstruction in these areas would be even more detrimental to wilderness values.

Impacts on Recreation

The Alpine Lakes Wilderness provides substantial recreational opportunities, and the Enchantment Permit Area, where the project is located, is a popular hiking and camping area that draws people from across the state and beyond. Recreation in the Eightmile area includes hiking, backpacking, fishing, rock climbing, and stock use.

Operation of the rebuilt dam under Alternatives 1 and 2 would result in higher seasonal lake levels, reducing the shoreline area available for recreation by approximately four feet and affecting informal routes near the lake. The Department of Ecology anticipates that hiking trails and backcountry camping areas would not be affected.

The summer brings high visitation and use to the Eightmile Lake area. Noise from construction would be noticeable to recreational users in the area, especially during helicopter use. The draft Environmental Impact Statement does not include details about closure times and more specific impacts to recreational activities. Our comments will request more information about the impacts to recreationists.

Share Your Comments

The Department of Ecology will consider all of the comments submitted by June 5, 2023, and move forward by deciding on a course of action and releasing the final Environmental Impact Statement this winter. The soonest construction would begin is summer 2024.

Our conservation staff is engaging with partners to comment directly on the draft EIS on behalf of our community. Mountaineers have deep connections to the Alpine Lakes Wilderness. In order to make the final Eightmile Dam replacement plan stronger and more favorable to Wilderness and recreation, we hope you’ll join us in commenting on the project’s draft Environmental Impact Statement online or by mail. Together we can make sure that our community’s voice is heard during this critical stage of the project’s planning process.

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Jeff Norman
Jeff Norman says:
May 22, 2023 12:27 PM

In addition to being a Mountaineer, I am a Life Member of Trout Unlimited. We are our nation's largest cold-water fisheries conservation organization. We protect, reconnect, restore and sustain quality cold-water fisheries. We are monitoring and discussing this project but have not written an official position yet. Thus, my comments are personal and may not represent TU's position. It is apparent that the Icicle-Peshastin Irrigation District (IPID) has a now-ancient water right and has special warranty deeds negotiated with the USFS that grants them the right to maintain/repair/rebuild the Eightmile Lake Dam, even though the lands have been within the Alpine Lakes Wilderness for forty-seven years. Regarding the fish within Eightmile Lake, everything should be done to avoid extreme changes in the lake water elevation. There are several species of Trout and Char that thrive in the lake. Fish stocking has occurred since the 1930's, and possibly earlier. This is a prime alpine lake fishing destination and the utmost care should be taken to protect them, even though they are not Anadromous or protected under a Tribal Treaty or the Endangered Species Act. Alpine lake fishing is a highly valued recreational activity and the health of these fish must be a priority. Below the lake, Eightmile Creek and other Tributaries contain native Cutthroat and native/ESA Listed Bull Trout. Further down in the Icicle drainage, there are ESA-listed Salmon. Some are wild and others return to the federal Icicle Hatchery. IPID is evidently not considering the effects of global warming and the resulting issues of stream temperatures and in-stream flow. Any plan must guarantee a Source-to-Ocean flow of instream water and water rights may need to be modified to make that guarantee absolute.