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John E. Schefter

Publications and source records attributed to John E. Schefter.

4 recordsLinked to original sources
USGS2010

External effects of irrigators' pumping decisions, high plains aquifer

The High Plains aquifer, which underlies about 174,000 square miles (1 square mile = 2.59 km 2 ) in the Great Plains, is the principal source of water in one of the nation's major agricultural areas. This paper examines relationships between the scale of management areas and physical factors, resulting from the lateral movement of groundwater, that limit the ability of irrigators in the High Plains to reduce their own future pumping lifts. At the scale of individual farms, irrigators have very limited ability to “bank” water in order to obtain reduced future pumping lifts. On the other hand, at the scales typical of regional management, reductions in pumpage will result primarily in reductions in water level declines within the management area.

Great Plains↗
USGS1980

An economic analysis of selected strategies for dissolved-oxygen management; Chattahoochee River, Georgia

A method for evaluating the cost-effectiveness of alternative strategies for dissolved-oxygen (DO) management is demonstrated, using the Chattahoochee River, GA., as an example. The conceptual framework for the analysis is suggested by the economic theory of production. The minimum flow of the river and the percentage of the total waste inflow receiving nitrification are considered to be two variable inputs to be used in the production of given minimum concentration of DO in the river. Each of the inputs has a cost: the loss of dependable peak hydroelectric generating capacity at Buford Dam associated with flow augmentation and the cost associated with nitrification of wastes. The least-cost combination of minimum flow and waste treatment necessary to achieve a prescribed minimum DO concentration is identified. Results of the study indicate that, in some instances, the waste-assimilation capacity of the Chattahoochee River can be substituted for increased waste treatment; the associated savings in waste-treatment costs more than offset the benefits foregone because of the loss of peak generating capacity at Buford Dam. The sensitivity of the results to the estimates of the cost of replacing peak generating capacity is examined. It is also demonstrated that a flexible approach to the management of DO in the Chattahoochee River may be much more cost effective than a more rigid, institutional approach wherein constraints are placed on the flow of the river and(or) on waste-treatment practices. (USGS)

Georgia↗
USGS1979

An economic analysis of selected strategies for dissolved oxygen management: Chattahoochee River, Georgia

Using the Chattahoochee River as an example, a method for evaluating the cost-effectiveness of alternative strategies for dissolved oxygen (DO) management is demonstrated. The conceptual framework for the analysis is suggested by the economic theory of production. The minimum flow of the River and the percentage of the total waste inflow receiving nitrification are considered to be two variable inputs to be used in the production of a given minimum concentration of DO in the River. Each of the inputs has a cost: the loss of dependable peak hydroelectric generating capacity at Buford Dam associated with flow augmentation and the cost associated with nitrification of wastes. The least-cost combination of minimum flow and waste treatment to achieve a prescribed minimum DO concentration is identified. Results indicate that, in some instances, the waste assimilative capacity of the Chattahoochee River can be substituted for increased waste treatment with the associated savings in waste treatment costs more than offsetting the benefits foregone due to the loss of peak generating capacity at Buford Dam. The sensitivity of the results to the estimates of the cost of replacing peak generating capacity is examined. It is also demonstrated that a flexible approach to the management of DO in the Chattahoochee River may be much more cost-effective than a more rigid, institutional approach wherein constraints are placed on the flow of the River and/or waste treatment practices.

Georgia↗