Modeling Local Aquifer Drawdown With MODFLOW

ISEF Category: Earth and Environmental Sciences

Subcategory: Water Science  ·  Difficulty: Advanced  ·  Setup: University Lab  ·  Time: Full Year

The Hook

A hidden water system can fail long before the taps go dry. Groundwater moves slowly, so small pumping changes can ripple through an aquifer for years. You can model that with real well data and see where drawdown might spread next. That turns a local water issue into a testable research project.

What Is It?

This project uses MODFLOW, a computer model for groundwater flow, to simulate how water moves through an aquifer. Think of an aquifer like a sponge underground. Wells pull water out of that sponge, and the water table drops around them. That drop is called drawdown.

Flopy is a Python package that helps you build and run MODFLOW models. You can feed it local well-log data, which tells you about rock and sediment layers underground, plus USGS water-level data, which shows how groundwater has changed over time. Then you can test future scenarios, like higher pumping or drier weather, and compare how each one changes the predicted water levels.

Why This Is a Good Topic

This is a strong science fair topic because you can test a real system with public data, clear inputs, and measurable outputs. The question matters to towns, farmers, and water managers who need to know how pumping and climate shifts affect groundwater supply. You can learn data cleaning, model building, calibration, and scenario analysis, all skills that matter in environmental research.

Research Questions

• How does increasing pumping from nearby wells change modeled drawdown in a local aquifer?
• What is the effect of different recharge assumptions on predicted groundwater levels?
• Does adding more detailed well-log layers improve model fit to USGS water-level records?
• To what extent do seasonal water-level patterns match the model under historical conditions?
• Which climate scenario produces the largest long-term drop in simulated water levels?
• How does the location of a new pumping well change the spatial pattern of drawdown?

Basic Materials

• Laptop with enough storage for Python and GIS files.
• Python installed with Flopy, Pandas, NumPy, Matplotlib, and SciPy.
• MODFLOW executable compatible with Flopy.
• Public USGS groundwater level data.
• Local well-log or borehole records from state or county databases.
• GIS software such as QGIS for mapping wells and model layers.
• Spreadsheet software for organizing data and checking units.
• Digital notebook for documenting assumptions, sources, and model choices.

Advanced Materials

• High-performance laptop or desktop with plenty of RAM.
• Python environment with Flopy, Pandas, NumPy, SciPy, Matplotlib, and GeoPandas.
• MODFLOW 6 executable and any needed preprocessing tools.
• GIS shapefiles for aquifer boundaries, rivers, land use, and pumping wells.
• Historical pumping records from water agencies or utility reports.
• Climate projection datasets from NOAA or NASA downscaled products.
• Calibration and uncertainty tools such as PEST or PyEMU.
• Version control system such as Git for tracking model changes.

Software & Tools

• Flopy: Builds, runs, and edits MODFLOW groundwater models from Python.
• QGIS: Maps wells, boundaries, and aquifer layers so you can check spatial patterns.
• Python: Organizes data, runs simulations, and plots drawdown results.
• Pandas: Cleans well and water-level tables before you feed them into the model.
• Matplotlib: Graphs hydrographs, maps, and scenario comparisons clearly.

Experiment Steps

1. Define the aquifer you want to model and gather the public data that describe it.
2. Choose the smallest model area that still includes your wells, boundary conditions, and likely pumping effects.
3. Build a simple layered structure from well logs, then decide how much detail you need for each layer.
4. Calibrate the model against historical USGS water levels before you test future scenarios.
5. Design scenario runs that change only one major factor at a time, such as pumping rate, recharge, or climate-driven recharge shifts.
6. Compare model outputs with maps and graphs that make drawdown patterns easy to interpret.

Common Pitfalls

• Using inconsistent elevation units, which shifts the whole water table and makes drawdown look wrong.
• Mixing wells from different aquifers, which creates a model that averages unlike water systems.
• Building too many layers from sparse well-log data, which gives false precision without real support.
• Calibrating only one time period, which can hide seasonal mismatch and poor long-term fit.
• Changing pumping, recharge, and boundary conditions at the same time, which makes it hard to tell which factor caused the drawdown.

What Makes This Competitive

A strong project goes beyond a basic model run. You would test how sensitive your results are to uncertain inputs, then show which assumptions matter most. You could also compare multiple future scenarios or use a calibration strategy that targets both seasonal and long-term water levels. That kind of careful analysis makes your work look like real environmental modeling, not just a classroom simulation.

Project Variations

• Model drawdown in a coastal aquifer and test how pumping changes the risk of saltwater intrusion.
• Compare two recharge scenarios, such as a wet year and a drought year, to see how groundwater responds.
• Add a new pumping well at different locations and measure how the drawdown cone shifts across the aquifer.

Learn More

• USGS National Water Information System: Search for local groundwater levels, well records, and water data by site.
• USGS Groundwater Data and Tools: Find guidance on aquifer data, monitoring wells, and groundwater methods on the USGS website.
• MODFLOW Documentation: Read the official model documentation and examples from the U.S. Geological Survey.
• Flopy Documentation: Learn how to build MODFLOW models in Python from the Flopy project site.
• NOAA Climate Data Online: Search for climate and precipitation data that can support recharge scenario work.
• MIT OpenCourseWare Hydrology courses: Find free lecture materials on groundwater flow, aquifers, and water balance.