Soil erosion is a major source of pollution in the United States. Erosion can cause both on-site and off-site damages. It has been argued that off-site damages are a significant component of soil conservation benefits and are currently not well known. Off-site effects of soil erosion are uncompensated externalities. Given significant external costs from erosion, there may be potential for net gains in social welfare from increased soil conservation. The major objective of this study was to examine, and where possible estimate, the off-site costs of soil erosion in the Willamette Valley. The value of erosion was measured in terms of increased production costs. These costs are incurred by economic agents in offsetting the effects of erosion. Six types of publicly owned enterprises were studied to determine erosion damages and related costs. These were municipal water supply, county and state road agencies, navigation supply, water storage reservoirs, and hydroelectric power plants. Of these enterprises, only water storage reservoirs and hydroelectric power plants did not incur substantial costs to offset the effects of erosion. Municipal water treatment costs were found to be significantly affected by erosion. A sediment damage function for the water treatment process was estimated using econometric modeling. The estimated coefficients relating suspended sediment and treatment costs indicated that the latter increased with an increase in river borne sediment. A 50 percent reduction in river turbidity experienced by the treatment plant studied would decrease chemical water treatment costs and sediment disposal costs by $4750 per year or approximately $4.55 per million gallons of water treated. A 50 percent reduction in sediment loads for the entire Willamette Valley would reduce municipal water treatment chemical costs by an estimated $231,000. An average cost analysis was also performed. This analysis indicated water treatment costs were $21.00 per million gallons of water treated. Inference to total municipal surface water supply in the Willamette Valley yielded an annual average erosion cost estimate, from natural and man made sources, of $1,052,000. County and state road maintenance departments must frequently clean drainage structures in response to sediment deposition from erosion. Benton county road maintenance costs, for sediment removal, were estimated to be approximately $222,000 per year in 1984 dollars. An inference to all county road departments in the Willamette Valley, yielded a total erosion cost estimate of $3,743,000 per year. State highway maintenance costs in the Valley due to sediment front erosion were estimated to be $503,000 per year in current dollars. Sediment removal involved with maintenance of a navigation channel on the lower reach of the Willamette river costs an average of $270,000 per year, expressed in 1984 dollars. Aggregate erosion costs for all these activities were estimated to be $4,758,000 per year in current dollars. This figure is equal to approximately $0.67 per acre and $432 per square mile for the Willamette Valley. These findings suggest that there exists potential for off-site benefits from increasing soil conservation activities in the Valley. However the economic feasibility of soil conservation projects in the Willamette Valley depends on their implementation costs as well as the on-site and off-site benefits. Cost studies of other activities impacted by erosion are needed to estimate the total off-site costs of erosion in the Willamette Valley.

Soil degradation has serious global impacts on agronomic, economic, and sociopolitical conditions, however, statistics regarding the degree of these impacts has been largely unreliable. This book aims to standardize the methodology for obtaining reliable and objective data on soil degradation. It will also identify and develop criteria for assessing the severity of soil degradation, providing a realistic scenario of the problem.

Masters Theses in the Pure and Applied Sciences was first conceived, published, SIld disseminated by the Center for Information and Numerical Data Analysis and Synthesis (CINDAS) * at Purdue University in 1957, starting its coverage of theses with the academic year 1955. Beginning with Volume 13, the printing and dissemination phases of the activity were transferred to University Microfilms/Xerox of Ann Arbor, Michigan, with the thought that such an arrangement would be more beneficial to the academic and general scientific and technical community. After five years of this joint undertaking we had concluded that it was in the interest of all con cerned if the printing and distribution of the volumes were handled by an interna and broader dissemination. tional publishing house to assure improved service Hence, starting with Volume 18, Masters Theses in the Pure and Applied Sciences has been disseminated on a worldwide basis by Plenum Publishing Cor poration of New York, and in the same year the coverage was broadened to include Canadian universities. All back issues can also be ordered from Plenum. We have reported in Volume 30 (thesis year 1985) a total of 12,400 theses titles from 26 Canadian and 186 United States universities. We are sure that this broader base for these titles reported will greatly enhance the value of this important annual reference work.

The purpose of this report is to produce a review on water resource valuation issues and techniques specifically for the appraisal and negotiation of raw (as opposed to bulk or retail) water resource allocation for agricultural development projects. The review considers raw water in naturally occurring watercourses, lakes, wetlands, soil and aquifers, taking an ecosystem function perspective at a catchment scale, and takes account of the demands from irrigated and rainfed agriculture. It is hoped that the review will have particular application to developing countries where agreed methods for reconciling competing uses are often absent, but nevertheless takes account of valuation approaches that have been made in post industrial economies.