Probabilistic bank erosion simulation for risk-informed levee integrity analysis

Authors: Langendoen, Eddy; Ursic, Michael - Mick; CHOWDHURY, SHYAMAL - Us Army Corp Of Engineers (USACE); RIVAS, TODD - Us Army Corp Of Engineers (USACE); CARMONA, YUNG - Us Army Corp Of Engineers (USACE); CHU, FREDA - Us Army Corp Of Engineers (USACE); COCHRAN, KELLIE - Us Army Corp Of Engineers (USACE); CANHAM, HAILEY - Us Army Corp Of Engineers (USACE); LIANG, JOHNSEN - Us Army Corp Of Engineers (USACE); AUBUCHON, JONATHAN - Us Army Corp Of Engineers (USACE); SHAKERI MAJD, MORTEZA - Us Army Corp Of Engineers (USACE); EOM, MOOSUB - Us Army Corp Of Engineers (USACE)

Submitted to: International Conference on Fluvial Hydraulics
Publication Type: Abstract Only
Publication Acceptance Date: 2/27/2020
Publication Date: N/A
Citation: N/A

Interpretive Summary: ABSTRACT ONLY

Technical Abstract: Previous feasibility studies and risk assessments found that bank erosion is a primary risk driver for levees along the Lower American and Sacramento Rivers that protect the City of Sacramento from flooding. The US Congress has allocated funds for the US Army Corps of Engineers (USACE) to improve the American levee performance, including reducing bank erosion related flood risk. USACE partnered with US Department of Agriculture (USDA) to modify the Bank Stability Toe Erosion Model (BSTEM) to allow for stochastic bank retreat numerical simulations to support risk-informed selection and design of erosion repair sites. Soil sampling and testing was used to inform initial soil erodibility and geotechnical BSTEM model inputs at selected sites. The BSTEM model was calibrated using survey and hydrologic data spanning multiple years and applying a consistent, repeatable procedure. The probability density functions of critical BSTEM parameters, including critical shear stress and erodibility coefficient, were developed for multiple soil types using results from soil erosion tests conducted on the American and Sacramento Rivers and input into a probabilistic BSTEM simulation. The results of the probabilistic simulations were plotted and used for risk-informed erosion repair site-selection and design. This large-scale project allowed collaboration between USACE and USDA to develop and use a new probabilistic bank erosion numerical simulation tool to identify levee or recreational areas that were most prone to bank erosion, helping to improve public safety for the Sacramento area in the most environmentally manner possible.