Simulating water-quality trends in public-supply wells in transient flow systems

Area of Science:

• Hydrogeology
• Environmental Science
• Water Resource Management

Background:

• Groundwater models are crucial for understanding water resources.
• Salt Lake Valley faces challenges with water quality and sustainable pumping.

Purpose of the Study:

• To adapt an existing groundwater model for particle tracking.
• To explain spatial trends in dissolved solids using advective particle tracking.
• To investigate the impact of pumping changes on groundwater age and source areas.

Main Methods:

• Utilized convolution-based advective particle tracking.
• Mapped mean groundwater age and source areas across the model domain.
• Calibrated the model using tritium concentrations to estimate effective porosity.

Main Results:

• The model supports the hypothesis of younger water and increased surface sources with changing pumping.
• Pumping-induced flow significantly influences groundwater age and source area dynamics.
• Model results indicate where changes in dissolved solids concentrations are expected.

Conclusions:

• Even simplified models can be valuable for understanding broad spatial trends in groundwater systems.
• Predicting specific water-quality changes at individual wells remains challenging.
• Model uncertainties stem from tracer inputs, transport parameters, and pumping data, but can be improved with more detail.