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Show Modern watershed management programs have un- folded from scattered efforts by individual farmers to prevent topsoil losses, to present land use practices and measures to obtain adequate cover control, reforestation and Federal and State purchase and management of marginal lan_ds. Various agricultural educational pro- grams are an additional factor in planned conservation. Projects Reviewed The following descriptions of typical projects were sub- mitted by the agencies and reviewed by the Committee. Corps of Engineer Projects 1. The Ty£art Reservoir, in West Virginia.-Author- ized in 1934 for flood control in the Pittsburgh area and water supply for navigation in the Monongahela River, was completed in 1938. Based on the results obtained to date, this pzroject has been an unqualified success. Total evaluated benefits of all types which have been provided to date aggregate about $22,500,000, or 122 percent of the first cost of the project. The experienced benefit-cost ratio is of the order of 2.23 to 1.0, compared to the original estimate of 1.38 to 1.0. Benefits realized from organic and acid pollution control and improvements of domestic and industrial water supplies were found to be much greateir than originally anticipated. Also, land enhancement in protected urban areas and recreation in connection with the reservoir have greatly exceeded those originally contemplated. The project has fulfilled its design purposes, and has realized substantial collateral benefits. 2. The Norfolk Dam, Arkansas and Missouri.-On the North Fork of the White River, this dam was authorized in 1938 for flood control; the power features were author- ized in 1941. It was completed in 1944. Basic data avail- able at the time the project was designed were adequate and very few, if any, modifications appear to be necessary. The project appears to be used economically, except for minor difficulties in sale of dump energy. The ratio of the benefits to cost since the project has been in operation is about 1.51 to 1.0, exclusive of in- tangible and recreational benefits. Although flood-control benefits were not stated in monetary terms in the author- izing documents, such benefits realized to date have greatly exceeded aver-age annual costs that would be allocated for that purpose. Average annual power benefits are about 1.5 times those originally estimated. Physical, economic, and political conditions appear to have been anticipated. Experience gained in this project, one of the first multiple- purpose reservoirs, has materialy assisted in formulation of procedures fo»r cost allocation, and in reservoir develop- ment for recreational purposes. The project has accom- plished its design purposes, and incidental benefits have been realized, from fish and wildlife propagation and recreation. 3. The Bojineville Dam, Oregon and Washington.- This Columbia River project was authorized in 1933 for navigation and water power. The initial project was completed in 1939 and additional power units were added up to 1943. It originated as a depression project, and detailed investigation and design were sacrificed to the desire to start work quickly. After construction of the spillway dam ~was begun, a more economical site was found about a quarter of a mile downstream, and the work was moved to the lower site. Two main power units were provided initially with substructure for four more and foundations for four additional units. These were the largest of their kind in the world up to that time. With the advent of World War II, the eight additional units were installed. The addi- tional generators had a larger capacity than the initial two, and considerable economy was realized from the experi- ence gained in the meantime. At the time the initial power units were installed, it was generally believed that they would suffice for a long time. The advent of World War II jumped the power demands and postwar progress has accelerated the need for power. Congress has recently authorized the con- struction of additional upstream storage reservoirs which will increase the potential power capacity at Bonneville. If the demand had been foreseen, some economy would be realized when additional units are added if structural provisions for even more than ten power units had been incorporated in the initial plans. The immense amount of power generated at Bonneville was a vital factor in meeting the manufacturing needs of World War II. The original plans contemplated tandem flight locks for the then commonly used small barges; these were changed during construction to a single lift 76- by 500- foot ship lock. Since completion of Bonneville Dam, new upstream locks are being built to 86- by 675-foot dimensions to accommodate the present type of barge tows. Studies are now being made of the economy of enlarging the Bonneville locks. Through cooperation with State and Federal agencies and to meet unprecedented requirements of preserving the salmon, an important national resource, fish-passing facilities were greatly expanded during construction from those originally contemplated. The project as a whole has an economic ratio in excess of 2 to 1, much higher than originally contempleted. It is accomplishing the purposes for which it was designed-to help in the economic development of the Northwest. Repayment orf the investment in the power features is ahead of schedule. It may be concluded from the experience gained at Bonneville, that ample preliminary investigations and analyses are necessary; that funds should be provided for definite planning prior to initiation of construction; and that large blocks of cheap power capacity when provided will readily be absorbed. 4. The Tionesta Reservoir, Pennsylvania.-This project is a single-purpose flood-control project designed as one of a system of reservoirs for the protection of the Pitts- burgh area. It was authorized in 1936 and completed in 1941. The project is being used economically. The ratio of benefits to costs of the project since completion is estimated at 4.57 to 1, compared to the original esti- mate of 1.24 to 1. The project has encouraged further growth of the Pittsburgh industrial area, and collateral recreational benefits have been realized. The project has fully accomplished its design purposes. 5. The Knightville Dam, Massachusetts.-This dam and reservoir in the Connecticut River Basin was author- ized in 1938 and completed in 1941. It is a single- purpose reservoir for flood control with provision for later adding spillway crest gates to insure the storage capacity 390 |