Gunda Corporation (GUNDA) has conducted scour analysis for over 120 bridges for TxDOT Austin District alone. GUNDA conducted field inspections of all bridges to assess the current channel depths and cross sections and gathered information such as;

  • as-built plans,
  • boring logs,
  • BRINSAP reports,
  • watershed characteristics,
  • existing hydraulic models,

as well as any available flood insurances, rate maps, and studies. From the gathered data GUNDA conducted hydrologic studies following TxDOT and/or FEMA criteria to obtain peak flows for multiple storm events up to 500-year. GUNDA developed a HEC-RAS model for each bridge to determine contraction scour and pier scour for the various storm events following Federal guidelines and a TxDOT standard methodology. GUNDA compared the computed scour with field assessed to determine the scour criticality of the bridge. From this analysis a scour summary sheet was prepared discussing the basis of the analysis, a description of the current conditions, rated the bridge based on the analysis and a recommendation on any further action.