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Aug 3 Denver Basin Model 
DWR > Data & Maps > Modeling / CDSS > Aug 3 Denver Basin Model

Denver Basin Aquifer Modeling


(Figure from: Paschke, S.S. ed., 2011, Groundwater availability of the Denver Basin aquifer system, Colorado: U.S. Geological Survey Professional Paper 1770, 11 p.)

In 1985, Senate Bill 5 provided a new framework to guide the appropriation of groundwater from the Denver Basin aquifers.  The Colorado Division of Water Resources (CDWR) staff developed individual models for each of the Denver Basin Aquifers: Dawson (Upper  & Lower), Denver, Arapahoe (Upper & Lower)  and Laramie-Fox Hills. These models were used to identify locations where the use of groundwater from the Denver Basin would have a minimal effect on the surface water system. An aquifer with this characteristic is legally identified as non-tributary.

These 1985 groundwater models are still used today to determine stream depletions for wells  in the not-nontributary groundwater areas of the Denver Basin aquifers.   More detailed information is available on the Denver Basin aquifers on the Denver Basin webpage of our website.

Around 2007, CDWR created an Excel interface to facilitate running the Denver Basin Models.  This interface and associated models are collectively known as AUG3.   A new version of AUG3 compatible with current operating systems is available as a zip file on the CDWR FTP website

Three separate applications are provided within the zip file:

  1. SB5_V2017:  This is the original version with a 5-year time step.  This version is the primary version to be used in Division 1 and 2 outside of the designated basins.
  2. DesignatedBasins_V2017:. This version is for use in the Designated Basins only.   Per requests from the Designated Basins folks, the alluvial aquifers of the original model have been revised to match new site-specific information for selected aquifer windows.
  3. SB5_1YearTimestep_V2017:  This is the same as the original version except it uses a 1-year time step. This version is for those few cases where a 5-year time step just will not do.

In addition, this zip file includes a revised User Guide for this program.