Assessing the Uncertainty in Water Budget Components within the Ozark Plateaus Aquifer System
Abstract
Comprehensive estimates of groundwater availability on regional scales may be computed through the use of groundwater-flow models. These models, in turn, contain uncertainty in observation targets, aquifer properties, and boundary conditions, which contribute to structural errors. The question therefore becomes, "What confidence is there in the prediction contribution of each water-budget component present in simulated future scenarios?" To address this question, linear uncertainty analysis is being done on a regional groundwater-flow model developed of the Ozark Plateaus aquifer system. The Ozark model encompasses approximately 176,000 square kilometers of parts of Arkansas, Kansas, Missouri, and Oklahoma and simulates seven hydrogeologic units over a history-matching period of 116 years. The model study area contains over 19,000 hydraulic-head targets and stream-seepage targets for approximately 81 named streams. Select well locations with continuous water-level records have been included as forecast observations to evaluate the reduction in parameter uncertainty related to forecast observations. While hydraulic-head forecasts are important to quantify the range in potential simulated values under future conditions, they typically apply to localized areas because of the low storage and permeability of the aquifer system. The larger purpose of the model, however, is in evaluating large-scale changes in water budget components such as discharge to streams, lateral flow through boundaries, and storage. Therefore, additional forecasts have been included that represent bulk water budget components. Based on the expanded forecast uncertainty analysis, an analysis of groundwater availability within a range of values produced by the distribution of potential parameter values is possible.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2017
- Bibcode:
- 2017AGUFM.H51G1368C
- Keywords:
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- 1807 Climate impacts;
- HYDROLOGY;
- 1829 Groundwater hydrology;
- HYDROLOGY;
- 1834 Human impacts;
- HYDROLOGY;
- 1880 Water management;
- HYDROLOGY