Gooseberry Neck Causeway, Outer Buzzards Bay
The Buzzards Bay Coalition, the Towns of Westport and South Dartmouth, and local residents are concerned with overall coastal resilience, and the impacts of human structures and climate change on water circulation and sedimentation patterns. Of note are the direct impacts that the Gooseberry Neck Causeway may have had on nearby coastlines and environments. This includes specific outcomes such as erosion along East Beach, and potential barrier breaching into the Let, spit dynamics along Allens Pond, and shoaling at the mouth to Slocum River embayment. More general issues includes receding shorelines, decreasing tidal exchange between bays and the coastal ocean, degrading marshes, and harbor/river mouth shoaling. These concerns have led to a series of scientific questions that focus on the Gooseberry Neck Causeway and its effects on coastal processes and resulting shoreline trends and water circulation patterns in the area between and adjacent to the Westport and Slocum Rivers
To addressing the questions, and predict existing and future sedimentation patterns along this section of coast this study couples observations with numerical modeling. Modeling allows us to replicate the hydrodynamic and sediment-transport conditions on a scale large enough to answer our questions, but with a level of detail that could not be accomplished through observation alone. Developing a model that covers this large section of coast provides us with a tool to study existing flow conditions and also enables us to project into the future to examine long-term effects of rising sea level, as well as the short-term impacts of major storms. However, for a numerical model to provide meaningful results, it needs to be well-tested and grounded in real data. Thus, we will also conduct a rigorous field campaign designed to acquire data to: 1) provide inputs to the modeling effort (bathymetric data, sediment data, water levels, wind and current measurements), 2) calibrate and test the model, and 3) obtain an understanding of the longer-term geomorphology of the region and the dominant hydrodynamic and sedimentation processes. We are also assessing the shoreline using historical images to determine rates of change and combining this with elevation data to calculate the volumes of sand removed or gained in certain critical zones.
