TxDOT personnel observed extensive and repetitive flooding along this divided four-lane road. The westbound lanes were built after the construction of a major reservoir upstream of the crossing, which was apparently the major factor in constructing the westbound lanes much lower than the eastbound lanes. HHR was retained to determine the cause of frequent flooding despite a major portion of the watershed being diverted away from the crossing. Our hydrology and hydraulics study of the Trinity River and related tributaries attributed flooding to backwater from Trinity River downstream of the crossing. Our hydraulic design report presented remedial design recommendations supported by hydraulic documentation, maps, exhibits, and models.