WRAP Manuals
WRAP is documented by six manuals published as Texas Water Resources Institute (TWRI ) technical reports. The manuals can be downloaded from the WRAP website as PDF files by clicking the links listed below.
Reference Manual (TWRI TR-255, August 2025, 464 pages)
Users Manual (TWRI TR-256, August 2025, 274 pages)
Fundamentals Manual (TWRI TR-283, August 2025, 116 pages)
Daily Manual (TWRI TR-430, August 2025, 346 pages)
Hydrology Manual (TWRI TR-431, August 2025, 271 pages)
Salinity Manual (TWRI TR-317, July 2009, 89 pages)
WRAP Case Study Guidance Reports
The following report entitled “Daily and/or Monthly WRAP Modeling System” extends the WRAP manuals by exploring capabilities and needs for supplementing monthly WRAP/WAM capabilities with newer developmental daily modeling options. Practical guidance and insight is provided employing Trinity and Nueces daily and modified monthly WAMs as case studies.
PDF Daily and/or Monthly WRAP Modeling System, Wurbs, TCEQ, 382 pages, November 2026.
An experience base accumulated by the Texas water management community over many years of WRAP/WAM modeling in Texas and more recent TCEQ-sponsored research and development at TAMU are synthesized in a 513-page December 2025 technical report entitled “Incorporation of Environmental Flow Standards and Other Water Management Complexities in Water Availability Modeling“, which for brevity is called the “Synthesis Report“. The Synthesis Report presents an overview of WRAP and the WAMs and explores hydrology and water management throughout Texas. Chapters 7-12 are research case studies employing developmental daily and modified monthly WAMs for the Brazos, Trinity, Neches, Colorado, Lavaca, and Nueces River Basins. The Synthesis Report can be accessed on the “Other Publications Page” of this website along with other reports covering the six case study daily WAMs.
Additions and Revisions Report
An Additions and Revisions Report describes the modifications to WRAP that have occurred over various periods of time. Development, improvement, and expansion of WRAP has occurred over many years and versions.
Example Datasets (Updates underway. Not currently Accessible)
Examples found in the WRAP manuals illustrate the concepts and methods covered. The Fundamentals Manual is organized around an example applying the WRAP programs WinWRAP, SIM, and TABLES and the USACE Hydrologic Engineering Center (HEC) program HEC-DSSVue. Some of the examples in the other manuals build upon and extend the example in the Fundamentals Manual. In some cases other relevant datasets associated with the examples are included along with the input datasets for the WRAP programs. All of the data files for the examples in all of the manuals can be downloaded together as a single zip file with filename WRAPexamples.zip. Alternatively, datasets for examples in each of the different manuals can be accessed and downloaded separately.