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1966), especially Recommendation 9(c), RFg1l1ation of r,ann1JRF, which recommended the preparation of preliminary reports for guidance in those areas where assistance is needed before a full flood plain information report can be prepared or where a full report is not scheduled. Authority for funding flood plain management studies is provided by Section 6 of Public Law 83-566, which authorizes the u.s. Department of Agriculture to cooperate with other Federal, state and local agencies to make investigations and surveys of the watersheds and rivers and other waterways as a basis for the development of coordinated programs. In carrying out flood plain management studies, the Natural Resources Conservation Service is responding to Executive Order 11988, entitled "Flood Plain Management," and Executive Order 11990, entitled "Protection of Wetlands" (both effective May 24, 1977). DESCRIPTION OF STUDY AREA A. Basin Characteristics The watersheds that produce runoff to Douglas Wash in Unincorporated Clifton are small in size (total area: 8.43 sq. miles), elevation ranges from 6,500 ft. to 4,620 ft. The upper half of the watershed, which is immediately north of Interstate HighWay 70, is semi-arid land in very poor condition. The lower half of the watershed from the Interstate HighWay 70 to the Colorado River is mostly cultivated agricultural land with residential sub-divisions concentrated in the upper portion of the western boundary. The length and width of the drainage are roughly 5 miles and 2 miles respectively, and an average channel slope of 280 feet per mile or 5.3 percent. The soils in the basin, along the stream channels, are mostly of hydrologic group B. They are moderately deep to very deep, well drained soil formed in mixed alluvium derived from Cretaceous Mancos Shales and other calcareous sedimentary rocks, (Hunter Canyon Formation, Mount Garfield Formation, and Sego Sandstone; all of which are sandstone and shale) . The vegetation in the watersheds north of the Interstate 70 is range land in very poor condition; south of Interstate 70 is mostly orchards and pastures in very good condition. The flood plains, within the study limits, generally contain typical residential and commercial property improvements such as buildings, yards, fences, streets, vehicles, etc. Vegetation such as lawns, shrubs, trees, flowers, and forbs are a part of the landscape. There are some willows and cottonwoods along those channels that have a sustained water supply. The channel does a considerable amount of meandering which enhances the visual aesthetics and wildlife habitat values in the area. It is also important to notice that, at several places along the reaches, the original stream channels are no longer there because of back- filling and land-leveling. 2 I I I I I I I I I I I I I I I I I I I