The second part of a much-anticipated Buzzards Bay-sponsored study finds the Gooseberry Island Causeway does not affect other surrounding beaches and water quality. Increasing sand at the mouth of the Slocums River and more frequent closings of the inlet to Allens Pond are not a result of the Causeway influencing the ocean currents and water flow there.
“We took on this research because there were long-held concerns that the Gooseberry Causeway was affecting the Bay shoreline” says Rachel Jakuba, the Coalition’s VP of Bay Science. “We convened a team of scientists in 2022 to study and better understand how this human structure interacts with the land and water around it, namely its effects on the beaches and water quality between the Westport and Slocums rivers.”
Because the scientists found that sand is deposited mostly during storm events, they predict that these Dartmouth areas will be affected even more with the progression of climate change and its greater storm frequency and intensity.
As the Slocum River continues to fill with sediment and water quality suffers, the Buzzards Bay Coalition has hired Falmouth-based Sustainable Coastal Solutions to further evaluate channel dredging options that might improve tidal circulation and water quality.
Sea level rise will have a more complicated effect on the inner estuaries. Rising sea levels increase the amount of water filling estuaries on high tides, which will help to keep inlets open. While rising water levels will drown salt marshes, sand washed onto or adjacent to salt marshes during storms can help build the salt marsh vertically, helping it survive rising sea levels.
The scientists, from Boston University, Woods Hole Group, and Virginia Institute of Marine Science, found in the first part of that study that the Gooseberry Causeway is not affecting the flow of water to the Westport River or its water quality, and it is not causing or accelerating erosion at East Beach. For more on the first part of the study, go here.
For part 2 of the study, go here.
