Groundwater Availability Analysis of the Denver Groundwater Basin

Science Center Objects

The Denver Basin aquifer system is a critical water resource for growing municipal, industrial, and domestic uses along the semiarid Front Range urban corridor of Colorado. The confined bedrock aquifer system is located along the eastern edge of the Rocky Mountain Front Range where the mountains meet the Great Plains physiographic province. Mining, transportation, agricultural,
and urban activities developed along the Front Range beginning in the 1800s, and today urban and suburban land use extends north from Denver to Fort Collins and south to Colorado Springs.

Continued population growth and the resulting need for additional water supplies in the Denver Basin and throughout the western United States emphasize the need to continually monitor and reassess the availability of groundwater resources.

Adequate monitoring and modeling of the hydrologic system are important to evaluate the effects of continued pumping on storage depletion and provide tools for future water management decisions.

 

Background:

In 2004, the U.S. Geological Survey initiated large-scale regional studies to provide updated groundwater-availability assessments of important principal aquifers across the United States, including the Denver Basin. This study of the Denver Basin aquifer system evaluates the hydrologic effects of continued pumping and documents an updated groundwater flow model useful for appraisal of hydrologic conditions.

To assess the effects of development on Denver Basin groundwater resources, transient groundwater flow in the bedrock and overlying alluvial aquifers was simulated for the period 1880 through 2003 by using a fully three-dimensional groundwater
flow model. The model uses the modular finite-difference groundwater flow computer program MODFLOW-2000 and includes several enhancements over previous modeling efforts because of additional data availability, improved modeling capabilities, and improved computer technology.  Groundwater budget and hydraulic head results from the calibrated Denver Basin groundwater
flow model were evaluated to describe the system response to continuing development, and model sensitivity results were used to identify geographic areas of the system where additional data collection would be most beneficial. Model predictions for the period 2004 to 2053 provide estimates of the future hydrologic system response and allowed computation of the predictive sensitivity of the model results to various parameters. The Denver Basin groundwater flow model is a useful tool for analyzing past and present conditions, predicting future aquifer response to continued development, and evaluating future hydrologic monitoring and assessment.

OBJECTIVES:

  1. To enhance understanding of regional ground-water flow and aquifer storage in the Denver Basin and surficial aquifers.
  2. To evaluate water-level declines, changes in aquifer storage, and stream-flow depletions resulting from Denver Basin aquifer pumping and predict future conditions based on projected water-use estimates.
  3. To evaluate the existing water-level monitoring and recommend improvements.
  4. Develop a three-dimensional groundwater flow model to further understanding of groundwater flow, water budget, and storage in Denver Basin aquifers.