FLOOD PROTECTION FOR THE HENDERSON BAYOU WATERSHED

摘要

The Henderson Bayou Watershed in Ascension Parish, Louisiana, includes the town of Galvez, Louisiana, and has an area of approximately 14 square miles. The main channel of Henderson Bayou begins near the intersection of Misty Oak Court and N. Burnside Avenue. It flows southeast until it crosses Henderson Bayou Road. From there, the channel flows northeast until it eventually discharges into the Amite River. Flood management facilities were recommended in a preceding watershed study to protect against backwater flooding from the Amite River. That study showed major flooding within the Henderson Bayou Watershed resulting from backwater from the Amite River. Based on the previously completed watershed hydrology report, and due to the various flooding sources, the focus was designing a flood protection structure for a 10-year Amite River backwater event. The proposed project includes flood gates to maintain the existing level of service within the watershed when the Amite River is under normal conditions. Because backwater events could potentially occur in conjunction with large storm events, the design includes a pump station to reduce the potential for flooding of structures within the watershed when all gates are closed. This paper presents the final design and construction of the flood management facilities consisting of a proposed stormwater pump station, flood protection levee, and flood gate structure upstream of the Amite River confluence. The flood gate system consists of four bulkhead gates including one for the navigation channel to maintain navigation in the bayou. Also, the project includes a levee system that ties into the west side of the pump station/flood gate structure and extends in a westward direction in order to complete the backwater prevention protection system The system is currently under construction (Figure 1).