S65a Scour Investigation (FL, USA)

As a result of active 2004 and 2005 hurricane seasons, many SFWMD canals experienced bank and bed erosion. The erosion was more severe downstream of flow control structures, particularly spillways and weirs. Erosion on the discharge canal can potentially endanger the structural stability of the flow control structure. Erosion of the banks may also result in damages to the levees. Severe levee damage may cause breaching, which poses a risk of flooding and consequently life loss and property damage. The sediments from canal erosion may also be carried by the flow to the lakes and reservoirs and deposited there, resulting in reduction of storage capability for water supply and deterioration of the water quality. The purpose of this project was to collect preliminary measurements of erosion (e.g., bed stream survey, scour mapping, sediment and flow characteristics) at the District water control structure S65A, located on the Kissimmee River, Florida. The study provided data and a better understanding of the erosion problems for S65A. The understanding gained during this effort was used to help develop remedial measures for District sites with existing erosion problems as well as preventive measures for District structures that may potentially face erosion problems. The approach was to deploy two boats equipped with ADCP/GPS systems to map the bathymetry upstream and downstream of S65A and to collect 2D discharge profiles and vertical velocity profiles to support the sediment transport model parameterization.