Publications by authors named "David R Steward"

Groundwater provides a reliable tap to sustain agricultural production, yet persistent aquifer depletion threatens future sustainability. The High Plains Aquifer supplies 30% of the nation's irrigated groundwater, and the Kansas portion supports the congressional district with the highest market value for agriculture in the nation. We project groundwater declines to assess when the study area might run out of water, and comprehensively forecast the impacts of reduced pumping on corn and cattle production.

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The steady-state head within a fully penetrating well may be estimated by evaluating the Thiem equation at the radius of the well. A method is presented here to extend results from the Thiem equation to horizontal wells and to partially penetrating wells. The particular model used in this investigation is based upon the analytic element method; it accurately reproduces a boundary condition of uniform head along the cylindrical surface at the perforated face of the well.

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Comprehensive studies of water resources systems require integration of modeling tools and data associated with individual processes. An object-oriented approach is presented here that associates ground water models based upon the analytic element method (AEM) with geographic information system (GIS) geodatabase features using an AEM Model Interface. Each aquifer object contains a prescribed geometry, a mathematical representation in the AEM, and GIS hydrogeologic data.

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