BUILDING LAND IN COASTAL LOUISIANA Expert Recommendations for Operating a Successful Sediment Diversion that Balances Ecosystem and Community Needs Page 1 Supplemental Information Table of Contents HYDRODYNAMICS IN THE RIVER .......................................................................................................................... 01 Pulsed Flows ............................................................................................................................................................. 01 River Discharge ......................................................................................................................................................... 01 Maximizing Diversion Efficiency ................................................................................................................................. 02 Sediment Availability ................................................................................................................................................. 03 Other Factors ............................................................................................................................................................ 03 HYDRODYNAMICS IN THE BASIN ......................................................................................................................... 04 Channel Development .............................................................................................................................................. 04 Residence Time ......................................................................................................................................................... 05 Water Levels ............................................................................................................................................................. 05 SEDIMENT ............................................................................................................................................................... 06 Channel Development and Sediment Transport ........................................................................................................ 06 Sediment Retention .................................................................................................................................................. 06 Sediment-Water Ratio ............................................................................................................................................... 08 WATER QUALITY .................................................................................................................................................... 09 Salinity ...................................................................................................................................................................... 09 Temperature ............................................................................................................................................................. 09 Nutrients .................................................................................................................................................................. 11 Hypoxia .................................................................................................................................................................... 11 Phytoplankton and Harmful Algal Blooms ................................................................................................................. 12 Sediment .................................................................................................................................................................. 12 Disease, Pathogens, Hormones and Pharmaceuticals ................................................................................................. 12 WETLAND HEALTH ................................................................................................................................................. 13 Habitat Types ............................................................................................................................................................ 13 Vegetation ................................................................................................................................................................ 13 Sediment Input ......................................................................................................................................................... 14 Biogeochemistry ....................................................................................................................................................... 15 Timing and Duration of Flooding .............................................................................................................................. 15 FISH AND WILDLIFE POPULATIONS ...................................................................................................................... 17 Productivity and the Food Web ................................................................................................................................. 17 Wildlife Habitat ........................................................................................................................................................ 17 Fish and Shellfish Habitats ........................................................................................................................................ 18 Specific Species Information ..................................................................................................................................... 19 American Alligator .................................................................................................................................................... 19 Page 2 Table of Contents Blue Crab ................................................................................................................................................................. 20 Bottlenose Dolphin ................................................................................................................................................... 20 Eastern Oyster .......................................................................................................................................................... 21 Finfish ....................................................................................................................................................................... 22 Mammals ................................................................................................................................................................. 23 Migratory Birds ......................................................................................................................................................... 23 Rangia Clams ........................................................................................................................................................... 23 Shrimp ...................................................................................................................................................................... 24 Waterfowl and other Water Birds .............................................................................................................................. 25 SOCIAL AND ECONOMIC ISSUES .......................................................................................................................... 26 Socio-Economic Effects ............................................................................................................................................ 26 Natural Resource Dependent Communities ............................................................................................................... 27 Flood Risk to Communities ....................................................................................................................................... 28 GOVERNANCE AND LEGAL ................................................................................................................................... 30 Decision-Making Structure and Process ..................................................................................................................... 30 Active and Meaningful Participation of People Affected by Diversions ....................................................................... 30 Outreach ................................................................................................................................................................... 31 Laws and Regulations ............................................................................................................................................... 31 Transitions and Mitigation ......................................................................................................................................... 33 MONITORING, RESEARCH AND ADAPTIVE MANAGEMENT ................................................................................ 35 Adaptive Management ............................................................................................................................................. 35 Monitoring and Research Plan ................................................................................................................................... 36 Hydrodynamics of the River 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