Metro Model

Regional Groundwater Flow Model for the Twin Cities Area

Groundwater is a vital resource that supports our drinking water, ecosystems, and local economies.
The Metro Model is a computer program that uses decades of data and cutting-edge science to simulate how groundwater moves, responds to climate and pumping, and interacts with surface water.
It’s a key tool for sustainable water planning—helping local agencies, planners, and communities make informed decisions today that protect water for tomorrow.

Why it matters
  • Groundwater supplies most of the region’s drinking water.
  • Groundwater is invisible, but its impacts are real—on drinking water, the economy, and ecosystems.
  • This model helps visualize, quantify, and plan for possible future conditions, like drought, land use changes, and population growth.
About Metro Model
An update to the model is in progress. 

Why update the model?
The current model is over 10 years old. As data improves and the region changes, an updated model offers:
  • More accurate results
  • Better tools to explore future changes—like new development, higher water use, or a changing climate
What’s changing
This effort starts by converting the Twin Cities Metro Groundwater Model (Metro Model 3) from MODFLOW-NWT to MODFLOW-6, evaluating alternative model grids, and preparing the tool for future planning and scenario applications.

Timeline
  • Phase 1 – Q4 2025: Conversion to MODFLOW 6 and data integration
  • Phase 2 – 2026/2027: Recalibration, scenario analysis, tool development
  • Phase 3 – Ongoing: Continued updates and stakeholder support

FAQs

A groundwater model helps us understand how water moves underground through layers of sediment and rock (aquifers).
Because real-world systems are complex, the model uses simplifying assumptions based on the best available science. These assumptions are part of what's called a "conceptual model" — basically, our simplified description of how the aquifer works.
Even though models aren’t exact copies of real systems, they are useful in many ways:

  • They combine data like water levels, recharge, and aquifer properties to check that everything works together
  • They help estimate things we can’t easily measure, like underground flow
  • They let us test "what if" scenarios, like changes in pumping or climate
  • They show where more data is needed to better understand the system

Purpose
The model helps planners, policymakers, and water managers in the Twin Cities area understand how changes in development, population, water use, and climate affect groundwater.
It supports long-term water planning by allowing users to test different scenarios, spot areas at risk, and make more informed, coordinated decisions. This regional groundwater model is designed to support broad-scale assessments of groundwater withdrawals, availability, and long-term sustainability across the region.
While it provides a strong scientific foundation, it is not intended for detailed local analysis without further refinement. Users seeking to conduct site-specific or local-scale evaluations should treat this model as a starting point or a source of regional context, and are encouraged to refine or supplement it with additional data and modeling appropriate to the local conditions and objectives.

Coverage area
The model covers 8,350 square miles and includes these eleven metro area counties: Anoka, Carver, Chisago, Dakota, Hennepin, Isanti, Ramsey, Scott, Sherburne, Washington, and Wright.

How it works
Metro Model uses the U.S. Geological Survey’s MODFLOW and daily Soil Water Balance (SWB) software to simulate how water moves underground. It integrates a wide range of data including:
  • Structural features: The ‘skeleton’ of the model – geology, wells, boundary conditions
  • Calibration targets: Observations that make the model behave like reality - measured water levels, baseflow in streams, aquifer properties, flow directions
  • Scenario data: Information for ‘what-ifs’ – growth, changing pumping rates, land cover, climate
The model is calibrated to reproduce observed groundwater levels and flows, ensuring it reliably reflects past and present hydrologic conditions.
The model outputs information about simulated groundwater levels, flow directions, and exchanges between groundwater and surface water.
This framework supports regional scenario testing to explore the effects of land use, water demand, and climate changes.

Metro Model has already proven valuable to water planning.
As a source of information or a starting point for more local modeling

  • Wellhead Protection Planning – The model has been used by communities and the Minnesota Department of Health as a starting point for local wellhead protection area delineations
  • Groundwater Contamination and Water Use Assessments – The model has been used by the U.S. Geological Survey, Minnesota Pollution Control Agency, and Minnesota Department of Natural Resources as a reference for hydrogeologic characteristics to frame more localized and detailed modeling projects
To support ongoing regional planning and policy exploration
Because Metro Model can be used to explore different “what if” scenarios, it is a useful tool for informing regional water plans and programs.
The Met Council’s first Metro Model provided foundational information for the first Metro Area Water Supply Plan and later updates. Results also helped to target the Met Council’s first water efficiency grant program, which has since expanded.
Going forward, Metro Model can continue to support decisions that consider the whole water system (not just wells) – because the model can simulate interactions between groundwater, surface water, streams, wetlands, and recharge zones.
  • Growth and development – The model enables assessment of how new development, population increases, or changes in land use will impact groundwater levels, aquifer stress, and water supply. This can shape conversations around zoning, planning, and infrastructure decisions.
  • Climate change and resiliency – The model can include climate projections (precipitation, recharge) to test how groundwater systems respond, helping to plan for extreme events.
  • Conservation and sustainability – The model can supports policies and programs for conservation by allowing “what‐if” modeling of conservation measures: e.g., reducing demand, changing land cover, sustainable pumping.
  • Monitoring, data, and assessment - The model identifies where data gaps or poor understanding exist (e.g. poorly characterized aquifers or uncertain recharge), helping target monitoring efforts.Who is involved?
Users
  • Local planners – the model can provide context for water-related policies and action plans
  • Water utilities – the model can be a starting point for wellhead protection planning
  • State agencies – the model can be a starting point for groundwater analyses
  • Researchers – the model can improve understanding of groundwater systems
Developers
  • Metropolitan Council (lead)
  • Barr Engineering Company (technical lead for Metro Model 2, Metro Model 3, and Metro Model 4)
  • Young Environmental Consulting Group (engagement lead for Metro Model 4)
Technical advisory group
A technical advisory group is convened whenever Metro Model is updated. This group is intended to bring perspectives from a range of stakeholders into the process:
  • State water agencies
  • Watershed organizations
  • County and city staff
  • Academic researchers

Downloads

The following files are for Metro Model Version 3. Version 4 files will be added when the model update is complete.
On request, these publications will be made available in alternative formats to people with disabilities. Call Metropolitan Council at 651-602-1140 or TTY 651-291-0904.

Metro Model 3 Report (2 MB), PDF
Metro Model 3 Report Figures (62 MB), PDF
Metro Model 3 Appendix A Updated Daily Soil Water Balance (SWB) Model (37 MB), PDF
Metro Model 3 Appendix B Parameter Sensitivities (920 KB), PDF
Metro Model 3 Appendix C Measured and Simulated Head Change at Minnesota DNR Observation Wells 1995 to 2011 (37 MB), PDF
Metro Model 3 Appendix D Well Identification for MNW2 Package (2 MB), PDF
Metro Model 3 Appendix E Geologic Data Sources (3 MB), PDF
Metro Model 3 Appendix F Stratigraphic Column of Paleozoic and Middle Proterozoic Bedrock in Southeast Minnesota (5 MB), PDF

Metro Model 3 Vistas (1.08 GB), zipped Groundwater Vistas (Version 6) model files
 Note: the model employs MODFLOW-NWT
Metro Model 3 text-based files (30 MB), zipped MODFLOW-NWT text based files

Metro Model 3 Boundary Conditions (1.75 MB) zipped Arc GIS (Version 10.1) ArcGIS point and polygon features of Groundwater Vistas model boundary conditions (No-Flow, Constant Head, and River)
Metro Model 3 Calibration Targets (4.99 MB) zipped Arc GIS (Version 10.1) ArcGIS point features of static water level, aquifer test, and baseflow calibration targets. Dataset includes model residuals
Metro Model 3 Hydrogeologic Property Grids (12.91 MB) zipped Arc GIS (Version 10.1)
Metro Model 3 Model Layer Elevations (9.68 MB) zipped Arc GIS (Version 10.1) ArcGIS point and polygon features defining the elevation of each model layer
 

Metro Model 3 User Manual (3 MB), PDF
Metro Model 3 User Manual Tutorials (8 GB), Zipped Groundwater Vistas (Version 6) model files

Contact Us

Lanya Ross
651-602-1803
[email protected]