Modernize Hydrologic Prediction Processes by Creating Custom Statewide SSURGO Green and Ampt Parameter Database Task 1: Hydrologic Methodology Assessment

The current edition of the Nevada Department of Transportation (NDOT) Drainage Manual was published in December of 2006, but new methods and technologies have emerged that have made hydrologic analyses more consistent between models with a higher degree of accuracy and reproducibility. NDOT Hydraulics is proposing to incorporate these new tools and methods, as they have been shown to significantly improve accuracy and reliability and thus improve designs and provide more consistent project cost estimates. This Hydrologic Method Assessment Report (Assessment Report) presents the results of the principal investigator (PI)’s review of collected data and includes the selected course of action based on the review and feedback received from NDOT’s review committee. The Assessment Report presents the results of the research and data collection as well as a discussion of the advantages of implementing methodology changes. A review committee appointed by NDOT will make the final determination of any proposed updates. The PI recommends that NDOT apply the use Green and Ampt rainfall loss estimation method for computing rainfall losses consistent with the 2014 ADOT Hydrology Manual. The PI also anticipates: 1) Compilation and development of GIS databases containing the new parameters for the Statewide (STATSGO2) Soil Survey as well as the existing published detailed (SSURGO) surveys; 2) Preparation of a guidance document that outlines the computational database processing technique used to develop Green and Ampt parameters for Nevada soil surveys; 3) Preparation of an internal self-help document to aid NDOT in the application of the Green and Ampt methods when using HEC-HMS.

Language

  • English

Media Info

  • Media Type: Digital/other
  • Features: Appendices; Figures; Maps; References; Tables;
  • Pagination: 26p

Subject/Index Terms

Filing Info

  • Accession Number: 01841314
  • Record Type: Publication
  • Report/Paper Numbers: 19Q2-E2-01, P674-19-803
  • Files: NTL, TRIS, ATRI, STATEDOT
  • Created Date: Apr 1 2022 8:57AM