Simulating a lake as a high-conductivity variably saturated porous medium
Ting Fong May Chui1, David L Freyberg
1Department of Civil and Environmental Engineering, Stanford University, Stanford, CA 94305, USA. maychui@stanford.edu
Ground Water
|July 16, 2008
Summary
Simulating groundwater-lake interactions is simplified by treating lakes as high-conductivity zones in variably saturated models. This method offers results comparable to complex simulations, enhancing groundwater flow analysis.
Area of Science:
- Hydrogeology
- Environmental Engineering
- Computational Modeling
Background:
- Groundwater-lake interactions are crucial for water resource management.
- Previous simulations used fully saturated models, limiting broader application.
- Existing variably saturated codes lack explicit coupled lake-water balance modeling.
Purpose of the Study:
- To extend the high-conductivity region approach for simulating groundwater-lake interactions in variably saturated models.
- To provide guidelines for parameter selection in variably saturated models.
- To assess the efficacy of this approach compared to traditional methods.
Main Methods:
- Incorporating the lake as a high-conductivity region within the groundwater solution domain.
- Developing general guidelines for saturated hydraulic conductivity, moisture retention, and relative permeability curves.
- Applying the method to an example groundwater-lake system and comparing results with a specified head boundary model.
Main Results:
- Model results using the high-conductivity region approach closely matched those from a specified head boundary model.
- The approach is effective for simulating groundwater-lake interactions in variably saturated conditions.
- Guidelines for parameterization were successfully developed and applied.
Conclusions:
- The high-conductivity region approach offers a viable and simpler alternative for simulating groundwater-lake interactions in variably saturated models.
- This method is particularly suitable for simpler geometries and lakes with less dynamic fluctuations.
- It facilitates the use of public domain variably saturated codes for integrated hydrological studies.
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