A water and sediment budget for the lower Mississippi–Atchafalaya River in flood years 2008–2010: Implications for sediment discharge to the oceans and coastal restoration in Louisiana

摘要: Summary The Mississippi is the largest riverine system in North America and one of most engineered rivers world. challenges studying River are due to its complex sediment–water dynamics multi (and often competing) uses for resources. Flood control navigation primary factors that how river managed. A third factor use resources, namely water sediment, nourishing degrading coastal wetlands states Louisiana Mississippi. As such, these must be fully considered coordinated while investigating developing techniques harness sediment resources restoration. This paper presents a detailed suspended budget analysis lowermost Atchafalaya systems flood years 2008, 2009, 2010. Data were derived mainly from Federal State measurements discharge load at (1) monitoring stations along channel (2) boat-based made during specific project studies natural passes man-made diversions. present study was focused on 2008–2010 minimize influence budgets historical decline loads carried by as observed previous investigators take advantage recent improvements network. results show both distributary pathways efficient sequestering sediments, particularly larger (sand) size fraction. Approximately 44% total Mississippi + Red (80% sand) reaching Old Control structures split between distributaries sequestered upstream Gulf Mexico overbank storage bed aggradation. Increases aggradation linked loss stream power associated with exits Mexico. further decreased deep FY08–10 46% (water), 19% (total load), 1.4% (suspended sand). These patterns delivery have major implications dredging diversions planned