Water Resources Practice Lead Arcadis, Georgia, United States
Abstract Submission: Eden Landing Ecological Reserve is a nature reserve in Hayward and Union City along the east coast of San Francisco Bay in Alameda County, California. The reserve comprises 5,040 acres of former industrial salt ponds used as a low salinity waterbird habitat. As part of the larger South Bay Salt Pond Restoration project, the largest wetland restoration project on the West Coast of the U.S., this project aims to restore the former salt ponds in Eden Landing to tidal marshes that will provide critical habitat for the California Clapper rail and salt marsh harvest mouse and nursery habitat access to downstream migrating juvenile salmonids. A key component of the restoration project is a diversion from the lower portion of the Alameda Creek channel through the right levee (facing downstream) and into the former salt ponds north of the channel. This diversion is intended to carry flow, sediment and fish north into the former salt ponds. The project must also maintain flood protection currently provided by the Alameda Creek flood control channel levees. The following hydrodynamic modeling tools were applied: • Delft 3D modeling of Alameda Creek, Old Alameda Creek and the former salt pond system in between the creeks in the Eden Landing area under current and future sea level rise scenarios to observe impacts of the proposed diversion to the former salt ponds and levee system. This model simulates flow and the movement of sediment from Alameda Creek through the proposed diversion and into the former salt ponds to support restoration design.
• Two dimensional HEC-RAS unsteady flow modeling of the tidally influenced lower reach of the Alameda Creek Flood Control Channel, system of adjacent ponds, and proposed diversion channel to support detailed design of the diversion channel geometry, elevation alignment and armoring required to meet project restoration goals.
