Second Powerhouse, Bonneville Lock and Dam, Columbia River, Oregon and Washington
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FINAL ENVIRONMENTAL STATEMENT 15 NOVEMBER 1971 s* »21 SECONDi t r 4 mA EM, ISa E * BONNEVILLE LOCK ANB DALI COLUnOlVEB, O ’ OREGON AND D fiS K T ON 11 f n U ;S ARMY; ENGINEER DISTRICT * ' > r* 4 S J- . * ' ' 'PORTLAND/OREGON k - ENVIRONMENTAL STATEMENT SECOND POWERHOUSE, BONNEVILLE LOCK AND DAM, COLUMBIA RIVER, OREGON AND WASHINGTON Prepared by U.S. ARMY ENGINEER DISTRICT, PORTLAND, OREGON 15 November 1971 Second Powerhouse, Bonneville Lock and Dam, Columbia River, Oregon and Washington ( ) Draft ( X ) Final Environmental Statement Responsible Office; U. S. Army Engineer District, Portland, Oregon. 1. Name of Action: ( X ) Administrative ( ) Legislative 2. tenance of an eig existing Bonnevil County, Washingto 3a. Environmental Impacts Highway and railroad relocations, removal of existing town of North Bonneville, excavation and disposal of about 18 million cubic yards of material, loss of about 25 acres of wetlands, increased mortality of downstream migrant fish, elimination of a popular sport fishing site, reduction of nitrogen supersaturation downstream from Bonneville, increased dependable capacity and electrical energy production for the Pacific Northwest power system. b. Adverse Environmental Effects: Relocation of the citizens of North Bonneville, filling of 400 to 600 acres of low elevation area downstream of the project with 18 million cubic yards of rock and soil, temporary turbidity during construction, noise and air pollution associated with construction activities. 4. Alternatives: No action, different powerhouse size, different power house location, addition of new navigation lock. 5. Comments Received: Federal Environmental Protection Agency Bureau of Reclamation Forest Service Bureau of Sport Fisheries & Wildlife Nat'l Oceanic & Atmospheric Admin. Geological Survey National Marine Fisheries Service National Park Service Bonneville Power Administration U.S. Coast Guard Bureau of Indian Affairs Federal Highway Administration Bureau of Outdoor Recreation Federal Power Commission State Oregon - Federal Aid Coordination Washington - Office of Program Unit Planning & Fiscal Management Idaho Fish and Game Department Skamania County, Washington Port of Skamania County Klickitat County, Washington Klickitat County Port District No. 1 City of North Bonneville, Wash. Port of Hood River Port of Portland 6 Draft statement to CEQ: 20 August 1971. Final statement to CEQ 1 0 APR ^72 ^ COVER SHEET SUMMARY SHEET CONTENTS PHOTOGRAPHS General Area Project Area DRAWING 1. ENVIRONMENTAL SETTING WITHOUT THE PROJECT 1-1 Scope -1 Columbia Basin geography 1-1 Columbia Gorge geography 1-2 Lower Columbia geography 1-3 Columbia Basin hydrology and meteorology 1-3 Columbia River water quality 1-4 Columbia Basin development and utilization 1-5 Columbia Basin hydroelectric development 1-6 Columbia Gorge utilization 1-8 Columbia River biota 1-9 The Dalles Reservoir 1-11 The Dalles Dam 1-11 Bonneville Reservoir 1-12 Bonneville Dam 1-13 Lower Columbia Features 1-14 Present river utilization 1-15 Anticipated modifications for peaking 1-18 2. PROJECT DESCRIPTION (DESCRIPTION OF THE PROPOSED ACTION) 2-1 3. THE ENVIRONMENTAL IMPACT OF THE PROPOSED ACTION 3-1 4. ANY ADVERSE ENVIRONMENTAL EFFECTS WHICH CANNOT BE AVOIDED SHOULD THE PROPOSAL BE IMPLEMENTED 4-1 5. ALTERNATIVES TO THE PROPOSED ACTION 5-1 No action 5_1 Other powerhouse sizes 5-2 Other powerhouse sites 5-2 Add new lock to proposed plan 5-5 Operation changes 5_5 6. THE RELATIONSHIP BETWEEN LOCAL SHORT-TERM USES OF MAN'S ENVIRONMENT AND THE MAINTENANCE AND ENHANCEMENT OF LONG TERM PRODUCTIVITY 6-1 7. ANY IRREVERSIBLE OR IRRETRIEVABLECOMMITMENTS OF RESOURCES WHICH WOULD BE INVOLVED IN THE PROPOSED ACTION SHOULD IT BE IMPLEMENTED ' _ _ 7_1 8. COORDINATION WITH OTHERS 8-1 Public participation 8-1 Government agencies 8-3 Comment and response 8-4 Citizen groups 8-45 Comment and response 8-45 Other recipients of the draft statement 8-46 LETTERS OF COMMENTS A-l COLUMBIA RIVER c SITE C NOTE5 Red indicates proposed work. ^POSSIBLE FUTURE SCALE I = 1200 NAVIGATION EXCAVATION a. Scope. - The environment that is to be studied, understood, and protected by the National Environmental Policy Act of 1969 and by the preparation and use of Environmental - Statements is the "human environ ment" - the most comprehensive environmental area that is reasonably definable. It includes the natural and physical environment that is man's habitat, the esthetic environment that is man's perception of his surroundings, the cultural environment that is man's history and heritage, the social environment that is man's organization of life's activities, and the interrelationships that exist between all of the above elements. A study of an environmental setting for a proposed project must attempt to identify and understand the human environment that may be significantly affected. It is clear that man's understanding of his environment will never be complete, so that any study of the environment is limited to the perception and understanding that is available at the time the study is made. Any action of major significance that occurs in the Columbia Basin affects, though often subtly or indirectly, many of the interrelated factors discussed above with impacts that may be important to the entire basin. For this reason, and to provide the reader with a full environ mental picture, coverage of the environmental.setting will include the entire Columbia Basin. b. Columbia Basin geography. - The Columbia River and its major southern branch, the Snake River, drain a total of 259,000 sQuare miles, including portions of British Columbia, Montana, Wyoming, Idaho, Nevada, Oregon, and Washington. The basin has maximum dimensions of 730 miles east and west, and 820 miles north and south. The Columbia River itself has its origins in Columbia Lake in Canada at elevation 2,650 feet, m.s.l. From Columbia Lake, the river flows in a northerly course to Mica, B.C., where it abruptly turns south and flows for 680 miles to the mouth of the Snake River. Along that route it collects waters from the western slopes of the Rocky Mountains, the Northern Cascade Range, and the Columbia Plateau of Washington. The Snake River sub-drainage begins at the base of the Teton Mountains in Wyoming, moves through the Snake River Plain in southern Idaho, collects the flows of the Salmon and Clearwater Rivers in central Idaho, and finally joins the Columbia River just downstream from Pasco, Washington. From that confluence the river flows a distance of 350 miles westward to the Pacific Ocean, bisecting the Cascade Range about halfway to the sea and forming the spectacular Columbia River Gorge. After the Columbia leaves the gorge it is joined by the Willamette River, the last major river to contribute to the flow of the Columbia. The Willamette follows a general northerly course and drains an area in northwestern Oregon bounded by the Cascade Range on the east, the Cala- pooya Mountains on the south and the Coast Range on the west. With the additional flow from the Willamette, the Columbia River turns north, then west again to pass through a gap in the Coast Range to the Columbia River estuary and the Pacific Ocean. The topography of the basin is characterized by numerous mountain ranges, gorges, vast rolling plateaus, and broad valleys. Numerous large lakes, comprising a total area of about 2,500 sQuare miles, exist in the basin as the result of glacial activity. More than 60 percent of the basin is above 4,000-foot elevation and 14 percent is above 7,000- foot elevation. Those high elevations are barriers to the moisture-laden winds moving in off the Pacific Ocean and have a definite influence on the climate and flora of the basin. The plains area, known as Inland Empire or Columbia Plateau, is a gently sloping area of 100,000 square miles in the central portion of the basin. It extends from central Oregon through central and eastern Washington into British Columbia. Another similar area is the Snake River plain which occupies most of southern Idaho. Those regions are relatively arid and contribute little to the flow of Columbia River. Before the river leaves the Great Basin environment of the Columbia Plateau to enter the confines of the Gorge, the banks of the river are still relatively open and the vegetation of the adjoining country is typical of the open range of the Basin: sagebrush, rabbitbrush, range grasses, and little or no timber. The climate is sunnier, and less sus ceptible to the violent changes, sudden sQualls, and rains that are common in the Gorge. The canyon walls are still sharply carved by the antecedent river, but expanses are broad. c. Columbia Gorge geography. - After the river enters the gorge the character of the terrain changes abruptly. The mountains which flank the gorge reach heights of nearly 5,000 feet above the stream. Cascading from plateaus above the river are numerous waterfalls, including 620-foot Multnomah Falls, highest in the Northwest. Shores are clothed in dark green conifers, principally Douglas fir, that extend to the river margin. Here the swift-flowing, abrading river has cut steadily into the uplift ing Cascade Range, to create a gorge of stark beauty. This is an area of cold, rain, dense fogs, and sudden frosts. Violent and unpredictable wind sQualls are frequent and are described in nearly every early account of river passage. Unlike the Great Basin complex, the cool and rapidly draining environment of the gorge is somewhat restrictive to many life forms. Vegetation appears lush, but is restricted in associations and species to the drier coastal conifer types, predominatly Douglas fir, with associated shrubs, herbs, and the ferns that are commonly found about the numerous small streams and waterfalls. Vines and berries are a dominant understory in much of the plant cover. A broad expanse of huckleberry exists on the somewhat warmer Washington slopes.