Related Experiment Video
Updated: May 30, 2026
12:44
Watershed Planning within a Quantitative Scenario Analysis Framework
Published on: July 24, 2016
A hybrid framework for improving recharge and discharge estimation for a three-dimensional groundwater flow model
Scott C Meyer1, Yu-Feng Lin, George S Roadcap
1Illinois State Water Survey, Prairie Research Institute, University of Illinois at Urbana-Champaign, Champaign, IL 61820, USA.. smeyer@illinois.edu
Ground Water
|July 30, 2011
Summary
This study improved groundwater flow model accuracy by refining recharge/discharge (R/D) zonation using PRO-GRADE and GIS data. More detailed R/D zones led to better model performance and stability.
Area of Science:
- Hydrogeology
- Geographic Information Systems (GIS)
- Numerical Modeling
Background:
- Accurate estimation of recharge/discharge (R/D) is crucial for effective groundwater flow modeling, especially in complex hydrogeologic settings.
- Existing models may have limitations in representing R/D heterogeneity, impacting simulation accuracy.
Purpose of the Study:
- To develop and evaluate alternative R/D zonations for a 3D groundwater flow model using the PRO-GRADE ArcGIS plug-in.
- To assess the impact of increased R/D zonation detail on model accuracy, stability, and mass balance.
- To investigate the utility of calibration statistics and supplementary GIS data in refining R/D zonation.
Main Methods:
- Utilized the PRO-GRADE ArcGIS plug-in to generate R/D zonations.
- Developed multiple R/D zonations (R12, R51) by intersecting PRO-GRADE output with existing model zones and incorporating GIS data.
- Created simplified R/D zonations (R40N, R30N, R28N, R18N) from R51 by removing zones based on calibration sensitivity and using the ArcGIS Nibble tool.
- Calibrated models using PEST and evaluated performance against stream discharge and head targets.
Main Results:
- All developed R/D zonations (R12, R51, R40N, R30N, R28N, R18N) showed improved accuracy compared to the original 4-zone model (R4).
- Improvements in simulating stream discharge targets were more significant than those for head targets.
- The refined models exhibited enhanced numerical stability and reduced mass balance discrepancies.
- PRO-GRADE estimates, guided by calibration and GIS data, improved R/D estimation in a complex 3D model.
Conclusions:
- Increasing the detail of R/D zonation significantly enhances the accuracy and numerical performance of groundwater flow models.
- PRO-GRADE, combined with calibration insights and GIS data, offers a robust approach for optimizing R/D zonation in complex hydrogeologic settings.
- Model simplification based on calibration sensitivity can yield accurate and efficient R/D zonations without sacrificing performance.
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