Environmental Impact Statement
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Final Environmental Impact Statement Elwha River Ecosystem Restoration Purpose and Need: The Elwha River ecosystem and native anadromous fisheries are severely degraded as a result of two hydroelectric dams (projects) and their reservoirs built in the early 1900s. Congress has mandated the full restoration of this ecosystem and its native anadromous fisheries through the Elwha River Ecosystem and Fisheries Restoration Act (Public Law 102-495). The Department of the Interior therefore finds there is a need to return this river and the ecosystem to its natural, self-regulating state, and proposes removing both dams to accomplish this purpose and fulfill the congressional mandate. Proposed Action: The U.S. Department of the Interior proposes to fully restore the Elwha River ecosystem and native anadromous fisheries through the decommissioning of Elwha Dam and Glines Canyon Dam and removal of all structures necessary, including all or part of both dams, powerhouses, reservoirs, and associated facilities to achieve this purpose. The proposed action is located in Clallam County, on the Olympic Peninsula, in Washington State. Lead agency: National Park Service Cooperating agencies: U.S. Fish and Wildlife Service, U.S. Bureau of Reclamation, U.S. Bureau of Indian Affairs, U.S. Army Corps of Engineers, and the Lower Elwha S’Klallam Tribe Type of statement: This is a final environmental impact statement. In preparing this, the Department of the Interior has adopted the majority of a draft environmental impact statement titled “Proposed Elwha (FERC No.2683) and Glines Canyon (FERC No.588) Hydroelectric Projects, Washington” as updated and renamed Draft Staff Report in March 1993 prepared by the Federal Energy Regulatory Commission. Also incorporated into the record of this environmental impact statement is the Elwha Report and its appendixes, prepared by the U.S. departments of the Interior and Commerce and the Lower Elwha S’Klallam Tribe (Jan. 1994). This environmental impact statement supersedes both the Federal Energy Regulatory Commission environmental impact statement and the Elwha Report. Abstract: In addition to the proposed action, four other alternatives are examined. They are: Dam Retention with mitigation measures installed for fish passage, Removing Glines Canyon Dam only and installing fish passage measures at Elwha Dam, Removing Elwha Dam only and installing fish passage measures at Glines Canyon Dam, and No Action (dams are retained without fish passage measures). The proposed action is also the Department of the Interior’s “preferred alternative.” Short term negative impacts from removing both dams could occur from sediment built up behind them. If sediment is allowed to erode naturally, the finer grained particles, such as silt and clay, could temporarily but significantly impact fish or other aquatic organisms. Impacts on water quality, river morphology, native anadromous and resident (i.e., trout and char) fisheries, living marine resources, wildlife, threatened and endangered species, vegetation, cultural resources, land use, recreation, esthetics, socioeconomics and river ecology are also examined in this environmental impact statement. Alternatives other than the proposed action may also have significant impacts on each of these resources. Difference between the Final and Draft Environmental Impact Statement: Comments were taken both orally and in writing for a period of 60 days on the draft environmental impact statement released in October 1994. The comment period ended December 23, 1994. Substantive comments were responded to both in a question and answer format and/or by making changes, additions or corrections in the text of the draft environmental impact statement. The changed draft is this document, Interior’s final environmental impact statement. Pg. 2 = pg. 0&i Summary In the early 1900s, the free-flowing Elwha River on the Olympic Peninsula in Washington State was blocked with two hydroelectric dams (See Figure 1). The Elwha Dam was built 4.9 miles from the mouth of the Elwha River beginning in September 1910. It impounded the reservoir known as Lake Aldwell. Construction on Glines Canyon Dam, 8.5 miles farther upstream, began in 1926, creating the reservoir known as Lake Mills. Although the dams helped in the early development of the peninsula, the presence and operation of the hydropower projects cause severe problems for anadromous fish, the ecosystem, and the Lower Elwha S’Klallam Tribe. The dams block the migration path for several species of salmon and trout, which, after maturing in the ocean, return to the Elwha to lay their eggs (spawn). Migrating fish such as these are anadromous. The dams also prevent or limit the downstream flow of nutrients, sediment, and woody debris the fish need to successfully spawn and rear juveniles, inundate fish habitat and result in elevated temperatures downstream. The Elwha River was used by 10 runs of salmon and trout before the dams were built. The fish fed more than 22 species of wildlife and were the basis of much of the culture and economy of the Lower Elwha S’Klallam Tribe. Because of the dams, the flow regime of the river changed from active meandering in many places to less active and more channelized. Reduced sediment supply from the river has caused the eastern edge of the pre-dam Elwha delta to erode, and the barrier beach at Freshwater Bay to recede and steepen. It has also contributed to the erosion of Ediz Hook, the sand spit that protects Port Angeles Harbor. In recognition of these problems, the Department of the Interior finds, consistent with congressional intent expressed in the Elwha River Ecosystem and Fisheries Restoration Act (P.L. 102-495; see Appendix), a need to fully restore the native anadromous fisheries and Elwha River ecosystem. For the purposes of Elwha River restoration, “full restoration” is interpreted by the Department of the Interior to mean reestablishment of natural physical and biological ecosystem processes, including recovery of the terrestrial and riverine habitat currently inundated by the reservoirs. Since the wildlife habitat and river upstream of the dams are in nearly pristine condition, removing the dams and fully restoring the 10 runs of salmon and trout would fully restore the Elwha River ecosystem. It would also return the cultural and economic focus of the Lower Elwha S’Klallam Tribe, uphold the federal trust responsibility to affected Indian tribes, and provide substantial long term benefits to sport fishing, tourism, and the local economies associated with these activities. The National Park Service has the lead in preparing this final environmental impact statement, which is a programmatic or policy environmental impact statement. The majority of the March 1993 Federal Energy Regulatory Commission Draft Staff Report was adopted as part of this document. The Elwha Report and its appendixes, prepared by the U.S. departments of the Interior and Commerce and the Lower Elwha S’Klallam Tribe (Jan. 1994), were also incorporated. Material in this document supersedes both that in the Draft Staff Report and in the Elwha Report. Pg. 3 = pg.ii&iv If the decision maker, the secretary of the interior; chooses the Proposed Action of removing both dams, the National Park Service will prepare a second environmental impact statement, the “Implementation EIS,” that would examine options for implementing the decision. Several alternatives for restoring fish habitat are examined in this programmatic impact statement. Only one alternative has the potential to fully restore Elwha native anadromous fisheries—the Proposed Action of removing both the Elwha and Glines Canyon dams. Chances for restoring nine of the ten runs of fish are rated as either “good” or “excellent” if both dams are removed (sockeye salmon suffer from potential stock limitation and habitat problems outside the confines of the Elwha River project and, therefore, have only “poor” to “fair” chances of returning in pre-dam numbers). Removing both dams would also restore natural flow conditions in the Elwha River. Figure 1. Location Map (Scan) Because federal agencies examine a full range of reasonable alternatives in an environmental impact statement, the National Park Service also analyzed leaving the dams in place and installing fish passage facilities, as well as removing each dam separately. These alternatives are Dam Retention (with passage facilities installed at both dams), Removal of Elwha Dam, and Removal of Glines Canyon Dam. No Action, or leaving the dams in place without mitigation measures (as they are now), was also analyzed to provide a basis for comparing all action alternatives. The chances of restoring native anadromous fish drop substantially under each of these alternatives. None of the ten runs has a good or excellent chance of full restoration if fish passage measures are installed (i.e., the Dam Retention alternative) or if Elwha Dam alone is removed. Although there is a good chance that both winter and summer runs of steelhead could be restored if Glines Canyon Dam were removed, the remaining eight runs do not fare as well. For all alternatives except Proposed Action, mortality associated with fish passage and poor habitat is likely to drive the Elwha pink salmon stock to extinction (if it is not already) and chum salmon stock to extremely low levels or extinction. Anadromous fish populations would return to normal if the dams were removed, and other features of the ecosystem would benefit as well. Natural sediment transport conditions would be reestablished if the dams were removed. This would restore needed spawning gravel and woody debris for fish, and also replace sand missing from the river’s estuary, nearby beaches, and the nearshore environment as far east as Ediz Hook. The estuary would grow to its pre-dam size and once again serve as an important transitional habitat between fresh and salt water for many species of fish and other aquatic organisms. Instead of a stable channel, the Elwha River would return to its active meandering morphology, creating the riffles, pools, and slower moving side channels that many anadromous fish prefer for spawning and rearing.