C. Watershed Management Program More than 60 per cent of the average annual natural runofí from the 11 western states originates on the public lands. Of that quantity, about 90 per cent is from Forest Service lands. Watershed programs on the public lands, therefore, can influence to a great extent the volume and quality of water yield from those lands. In this section there will be described the measures taken to improve watershed conditions on the public lands, the amounts invested in watershed programs on the public lands and on similar non-federal lands, a summary of lands acquired by the United States for watershed protection and the potential productivity of the public lands. Measures Taken to Improve Watershed Conditions on Public Lands. The primary measures taken to improve watershed conditions on Forest Service lands in the 11 western states are generally categorized under the following items: gully stabilization, sheet erosion control, stabilization of dunes and blowouts, streambank and lakeshore stabilization, rehabilitation of abandoned roads and trails, and mine restoration. The improvements under gully stabilization include special erosion and drainage measures required to stop gully formation. The measures consist of check dams and other structures or means necessary for stabilization of side slopes. From 1958 through 1966 more than 1000 miles of side slopes on Forest Service lands were treated to prevent gully developments. Sheet erosion control is designed to reduce erosion caused by overland flow and to reduce flood hazards. The control measures include special planting procedures using extra large stocks of trees, close spacing of trees, sodding, mulching, seeding, countour trenching, contour furrowing, and others. From 1958 through 1966, about 322, 000 acres of Forest Service lands were treated to control sheet erosion. Light soil areas on the forest lands subject to wind erosion are stabilized by constructing wind barriers, mulching, sodding, planting grass clumps, and planting closely spaced, rapidly growing trees. About 3,000 acres of such areas were treated on Forest Service lands during the period from 1958 through 1966. Streambanks and lakeshores are protected from erosion by special planting, gabion emplacement, or revetment construction. From 1958 through 1966 about 1000 miles of lake shorelines and streambanks on Forest Service lands were treated by such protective measures. Measures are also taken to control erosion from abandoned roads and trails caused by surface runoff. Treatment measures include construction of water bars, sloping of banks, reseeding to grass, and others. From 1958 through 1966 about 6,000 miles of abandoned roads and trails on Forest Service lands were rehabilitated by such measures to reduce erosion. Mine areas are corrected to restore proper hydrologic functioning, for esthetic purposes, and utility of surface areas disturbed by mining or prospecting. The corrective measures included formation of sloping high walls, vegetation, drainage, spill reshaping, and others. From 1958 through 1966 about 400 acres of mining. areas on Forest Service lands were treated by such measures. The primary measures taken to improve watershed condition on National Park lands, Bureau of Land Management lands, and Fish and Wildlife lands in the 11 western states are generally classified under the following items: water control structures, protective fencing, undesirable plant control, vegetation and other conservation practices. Water control structures are comprised of detention dams, dikes, diversion dams, and retention dams, These structures are not constructed for the primary purpose of water storage Other conservation practices include contouring, furrowing, pitting, water spreading, dune control, and deep tillage. Large areas of lands are treated for the purpose of brush control and weed: control. Investment for Watershed Rehabilitation on Public Land. A summary of expenditures by the Forest Service, National Park Service, Bureau of Land Management, and Fish and Wildlife Service for the purpose of watershed rehabilitation on National Forest lands, National Park lands, Bureau of Land Management lands, and Fish and Wildlife lands are presented in tables 46, 47, 48, and 49, respectively. The expenditures are classified by types of treatment and by state for the period of fiscal years from 1958 through 1966. Similar information for the lands administered by other federal agencies is not available. Table 46. Summary of Expenditures by the U.S. Forest Service for Watershed Rehabilitation on National Forest Lands by State, Fiscal Years 1958 through 1967. Table 47.Summary of Expenditures by the National Park Service for Watershed Rehabilitation on National Park Lands by State, Fiscal Years 1958 through 1967. b/ Records incomplete, estimates provided. Includes work completed pursuant to appropriations for soil and watershed conversion and range improvement. Includes contour trenches, pitting, furrowing, waterspreading, dune control and deep tillage. |