New Rainfall Coefficients – Including Tools for Estimation of Intensity and Hyetographs in Texas

Depth-Duration-Frequency (DDF) coefficients for Texas were updated from findings reported in Asquith (1998) and Asquith and Roussel (2004) and are herein referred to as the 2015—DDF values. The 2015—DDF values were used to estimate the 2015—ebd values to parameterize the intensity equation in the Texas Hydraulic Design Manual. Both sets of values are listed as appendices in the report. A computational tool named EBDLKUP-2015.xlsx was built to replace an earlier tool in common use in Texas. The tool differs from the earlier tool in appearance, and is password protected to reduce unintentional changes to the underlying database. The password and an alternate method to defeat the protection are provided in the Technical Reference Manuals as appendices in the report. A companion tool named TXHYETO-2015.xlsx was built to enable designers to rapidly generate Texas specific hyetographs for importing into HEC-HMS and similar hydrologic modeling software using an approximation to the tabulations reported in Williams-Sether and others (2004). Training tutorials, a training video, and a training module are included to facilitate rapid deployment of the tools. These components are listed as appendices in the report.


  • English

Media Info

  • Media Type: Digital/other
  • Edition: Final Report
  • Features: Appendices; Figures; References; Tables;
  • Pagination: 214p

Subject/Index Terms

Filing Info

  • Accession Number: 01633287
  • Record Type: Publication
  • Report/Paper Numbers: FHWA/TX-15/0-6824-1, 0-6824-1
  • Contract Numbers: 0-6824
  • Created Date: Mar 24 2017 4:43PM