This project presented the techniques of levee erosion repair and their hydraulic evaluation. For the project purpose a site located at San Joaquin River at River Mile 71.5, Right Bank (SJR RM 71.5R) has been selected. The site is located at as outside bend of a tight meander and is subjected to severe erosion. In this study, a simulation model using HEC-RAS hydraulic model has been performed to determine the existing hydraulic characteristics for the project design flow and 100-year flow and another simulation model has been performed to determine the impact of the repair to the existing system. The design of the erosion site involved alternative analysis and selection of most appropriate repair alternative, determining site existing hydraulic characteristics, determining repair cross-section using hydraulic characteristics, and evaluating impact of the repair on existing system. For alternative analysis, four alternatives have been considered and analyzed, and most feasible alternative - waterside repair (rock slope protection) has been selected as a repair option. Hydraulic characteristics of the River have been determined by using HEC-RAS hydraulic model. Using hydraulic characteristics and physical parameters of the site, the minimum required rock size for the site has been determined by using CHNL PRO software. The repair section for the erosion site has been determined by D50 rock size. As the repair is a waterside repair and is going to encroach into the available conveyance area, a hydraulic analysis is required to evaluate the impact of the repair to the existing system. Once the repair section of the site has been finalized, the impact of the repair to existing system has been analyzed by using HEC-RAS hydraulic model. The results of the analysis show that the repair has very little or insignificant impact on the existing system. If there were any adverse impact on the existing system due to the waterside repair, another alternative other than waterside repair would be considered as a remedy of the erosion problem.This project presented the techniques of levee erosion repair and their hydraulic evaluation. For the project purpose a site located at San Joaquin River at River Mile 71.5, Right Bank (SJR RM 71.5R) has been selected.
|Title||:||Hydraulic Evaluation of Levee Repair Techniques|
|Author||:||Syada Iffat Ara, California State University, Sacramento|