Exploring the Applicability of Detached Breakwaters to Prevent Ephemeral Inlets in Norton Point Beach, Chappaquiddick Island, MA
Loading...
Author(s)
Emerson, Ian Ross
Advisor(s)
Editor(s)
Collections
Supplementary to:
Permanent Link
Abstract
Norton Point Beach connects the two halves of Martha's Vineyard, Massachusetts, but it has breached repeatedly in the past, allowing severe erosion of Wasque Point and disrupting transportation. Attempting to predict the breaches, the GENESIS and later the GENESIS-T models were applied to simulate the beach using USGS geographic data and Martha's Vineyard Coastal Observatory wave data. Unfortunately, the 1-D model proved to have limitations: the beach likely breached from the bay side of the modeled shoreline, and there was no direct data from inside the bay. Multiple configurations consistently overestimated erosion of the eastern side of the beach while overestimating accretion on the western side.
Simpler attempts to model the breach conditions support local belief that a number of factors, including a preceding winter of erosive high waves and an unusually high tide, combined to cause a major breach on April 17, 2007. The analysis does not support any coastal construction to directly prevent a breach, although a detached breakwater could still enhance accretion at certain parts of the beach.
After exploring various varieties of breakwater, a floating breakwater was determined to be the ideal candidate: new models can handle higher waves than before and change location, while its non-permanent nature makes it ideal for a region with strong opposition to offshore construction.
Sponsor
Date
2020-08-21
Extent
Resource Type
Text
Resource Subtype
Thesis