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Water Rights Analysis Package (WRAP) Modeling System Reference Manual, 9th ed.

R. Wurbs

The Texas Water Resources Institute (TWRI), and many other agencies and organizations, have worked with Ralph Wurbs over the years to develop WRAP (the Water Rights Analysis Package). The WRAP model simulates management of the water resources of a river basin, or multiple-basin region, under a priority-based water allocation system. The model facilitates assessment of hydrologic and institutional water availability/reliability for existing and proposed requirements for water use and management. Basin-wide impacts of water resources development projects and management strategies may be evaluated. The software package is generalized for application to any river/reservoir/use system, with input files being developed for the particular river basin of concern. The model is documented by reference and users manuals that may be downloaded from this site along with the software. WRAP is incorporated in the Texas Commission on Environmental Quality (TCEQ) Water Availability Modeling (WAM) System.

You can contact Wurbs for more details at

The most recent version of WRAP manuals can be found at Ralph Wurbs' TAMU website,

Another excellent resource is the TCEQ website, At this website, you can download data input files for several river basins in Texas, as well as other resources that are helpful to run the TCEQ Water Availability Modeling System.

Note: Some of the other TWRI technical reports that provide information about Ralph Wurbs' WRAP research include TR-179, TR-146, SR 2002-020, and SR 2002-023.

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