Bitting School Road

The existing Bridge 193 on Bitting School Road at Branch of Wilbarger Creek was a multiple pipe culvert that overtopped after relatively brief rainfall events. The flooding before the bridge required closure of the road to local traffic, which limited access to residences along the road in the vicinity. Four hydraulic alternatives were evaluated to address the project objectives. The chosen alternative raised the low point in the road by approximately 4 feet so it would be slightly higher than the Wilbarger Creek Bridge by using five 12' x 12' multiple box culverts.

The project was in FEMA Flood Zone A and the roadway flooded frequently at the location of the culvert after moderate rainfall, making the crossing impassible to vehicular traffic. During design, in anticipation of the County approving and implementing NOAA Atlas 14 data (which resulting in higher rainfall intensities), American Structurepoint selected an interim 100-year criteria. The existing culvert was adjacent to Wilbarger Creek and when the creek over topped its banks, it combined flow at the culvert. To perform hydrologic analysis, an HEC-HMS model was created and included the five watershed areas and reach lengths that outfall into Wilbarger Creek.