Improved Understanding of Sediment Dynamics for the Coos Estuary - NERRS/NSC(NERRS Science Collaborative)

This project combined observations with the development of a hydrodynamic model to better understand and predict water and sediment flows in the Coos estuary. The project team collected time-series data of water properties including temperature and salinity, velocity, sediment type, and sediment concentration at monitoring stations in the Coos estuary, including the first bathymetric dataset to cover the entire estuary. These were combined with existing time series and maps. Using this data, the team developed a validated hydrodynamic model that skillfully reproduced observed water properties and sediment dynamics in the estuary over a range of forcing conditions (e.g., river discharge, winds, tides). The team then used the model to run two perturbation experiments that analyzed a proposed deepening and widening of the estuary’s main navigation channel and examined historic estuary conditions. The project provided users with a dynamic picture of estuary conditions and habitat, and has informed an update to the estuarine management plan and fisheries habitat maps, improved the success of oyster restoration projects, and increased data efficiency among community stakeholders.