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Show part centering around the quarry, is negligible at present. Recreational values exist, though they are undeveloped. The area offers excellent possibilities for the layman to see and learn interesting stories of the land forms and the plant and animal life of past geological periods, the early occupation by man, and the present plant and animal life. Over most of the monument the geological features- the thick sequence of rock formations of Paleozoic and Mesozoic ages, the structural folds and faults, and the rugged relief- blend with the scenic features and the wilderness characteristics to form a setting which offers many opportunities for education, spiritual uplift, and physical recreation, including camping, boating, horseback riding, hiking, and fishing. PROPOSALS BY THE BUREAU OF RECLAMATION Potentialities for using the water resources of the Green and Yampa Rivers within and near the national monument are being studied by the Bureau of Reclamation. Under consideration are proposals for the Echo Park and Split Mountain Dams, reservoirs, and appurtenant facilities. Echo Park Dam and Reservoir.- The proposed site of the Echo Park Dam is in the narrow inner gorge of the Green River at a point near the base of the tip of Harpers Corner. Normal stream elevation at this point is about 5,048 feet. At high water, currently being considered for elevation 5,550 feet, the reservoir would run throughout the length of the Green River Canyon within the national monument upstream from the dam, and would extend northwestward from the north boundary, through Browns Park, for a distance of 30 miles or more by river. Another arm of the reservoir would lie in the Yampa River Canyon, and would extend to a point in Lily Park east of the eastern boundary of the monument. Maximum drawdown might amount to 150 feet during periods of extreme drought. High- water levels could be expected to take place normally during July and August, with relatively high levels in September. Low water ordinarily would occur during the late winter months before spring runoff. Seasonal variation would be from 20 to 50 feet. The Bureau of Reclamation has not made a decision on the height of the dam, location of construction roads, construction camps, or power lines. It is planned to open a gravel pit in Island Park. Split Mountain Dam and Reservoir.- The proposed site of the Split Mountain Dam lies near the head of Split Mountain Canyon. A dam 118 feet high to raise the water surface to an elevation of 5,048 feet is being considered. A reservoir at that elevation would inundate Little, Rainbow, and Island Parks, and the bench land at the mouth of Jones Hole. Present studies indicate practically no fluctuation either seasonally or annually. Only in years of extreme drought would there be any radical lowering of water level. The Bureau's report of March 1946, on the Colorado River Basin states: " A power head of 200 feet could be utilized by means of a pressure tunnel in three sections, extending from the dam 8.3 miles downstream to a power plant 5 miles up the river from Jensen, Utah." EFFECTS OF PROPOSED DAMS, RESERVOIRS, AND RELATED STRUCTURES UPON NATIONAL MONUMENT VALUES Echo Park Dam and Reservoir.- Information to date indicates that the Echo Park Dam, reservoir, and appurtenant structures and facilities would not affect the Quarry Unit of the monument. They would, however, seriously and adversely affect the Canyon Unit. The dam would be totally alien to the geology and landscape of the monument. It would be seen from the upper end of Whirlpool Canyon and from points along the rims of the canyon, and, from the viewpoint of monument values, would be a lamentable intrusion. Power lines would have a widely damaging effect upon wilderness and scenic values. Development of a power project would require the introduction of construction and operation roads and other facilities which would otherwise not be built. They could hardly be constructed without injury to geological and scenic values of the Canyon Unit. Far- reaching effects upon scenic, geological, and wilderness values would result from impoundment of the Echo Park Reservoir. The two- arm artificial lake would cover wholly or in part a number of 196 |
