Photo above by R. Lawrence Swanson: An eroding bluff at Long Beach has been stabilized by constructing a stone seawall at the bluff’s base. The bluff has been terraced to capture material that rolls down from the top and can be planted with vegetation that will help stabilize it.
In a January 11, 2018 editorial on TBR Newsmedia titled “Your Turn: Forgotten North Shore vulnerable to sea level rise,” SoMAS Interim Dean Larry Swanson highlighted how the South Shore of Long Island is featured in the majority of proposals for preparing for the next big storm after Superstorm Sandy. According to Dr. Swanson, “the North Shore of the Island has been largely neglected in the sea level rise/storm surge discussions and planning even though it is equally vulnerable to these processes.”
The early March Nor’easter demonstrates the power of nature and the difficulty of implementing resiliency measures that are effective and affordable. The combination of wind, rain, and storm surge severely eroded the bluffs of Nissequogue on Long Island’s north shore. The photos clearly show the slumping of the morainal when left unprotected. However, stabilization measures were left wanting as well. The terraced slopes failed and even the hardened sea walls suffered damage. Comparison of Fall 2017 photos with those of March 4 2018 shows these situations along with the hanging stairs where some two to three feet of elevation were lost on the beach face.
Comparison of storm surge elevations in Stony Brook Harbor shows that by historical standards, the recent event was not as high as had been previously recorded. The undermining of the unprotected and stabilized bluffs could have been far worse and most likely will be in the future. New York State and the communities located along the north shore need to explore reasonable measures to protect that coastline including both the bluffs and the downstream barrier beaches that are maintained by the natural erosion of those bluffs.
|Date||Height above Mean Level Water||Height above Predicted High Tide|
|December 11, 1992||12.8||3.90||6.0||1.83|
|December 24, 1994||10.5||3.20||5.2||1.58|
|April 16, 1996||8.7||2.65||2.5||0.76|
|October 19, 1996||10.3||3.14||4.3||1.31|
|February 12, 2006||9.5||2.90||3.7||1.13|
|April 15, 2007||10.6||3.22||3.2||0.97|
|March 13, 2010||9.7||2.96||3.6||1.10|
|August 28, 2011
|October 29, 2012
|March 2, 2018
Table above from Swanson, R. L., & Bowman, M. J. (2016). Between Stony Brook Harbor Tides: The Natural History of a Long Island Pocket Bay. SUNY Press.