The Center for Coastal Studies has completed a two-year coastal resiliency and sea level rise study on Martha’s Vineyard which concluded that, on average, for every one-foot increase in the water level about 700 acres of land will become inundated.
Funded by the Massachusetts Office of Coastal Zone Management’s Coastal Resiliency Grant Program and the Martha’s Vineyard Commission, the study mapped a total of 716 Storm Tide Pathways (or the places where water will begin to flow inland for a given elevation) across the island.
The study, entitled Mapping Storm Tide Pathways in the Six Towns of Martha’s Vineyard: Assessing Coastal Resiliency to Storms and Sea Level Rise, found that for every six-inch increase in water level, approximately 350 acres of land are impacted, ranging from a low of 213 acres to a high of 778 acres.
The project also identified 47 Storm Tide Pathways that are only 12 inches above the previous storm of record for the Vineyard. These 47 pathways, which have not been flooded in almost 100 years, would inundate 767 acres.
The study also included a low-lying roads assessment for Martha’s Vineyard and found that a total of 36 roads island-wide will have at least one foot of water during Nuisance Flooding, the lowest flooding category from the National Weather Service. Minor Flooding would impact 68 roads; Moderate Flooding would affect 87 roads, and Major Flooding would impact 91 roads.
Approximately 20 miles across 58 roads will be flooded during in a Storm of Record Plus 1 Ft (SoR+1ft) category, a designation developed by Center for Coastal Studies researchers. It is critical to note that the flooding in this category occurs in areas that have not been flooded since at least 1938, and it is essential that Vineyard towns prepare for the inevitable flooding that will occur in these areas.
With sea levels rising, one of the highest risk areas is low-lying coasts. Since 2014 the Center for Coastal Studies has been mapping the paths that flowing water will take in low-lying coastal areas as a way to assist a town’s first responders, Department of Public Works staff and others who need to know where and when a storm’s flood waters might be flowing on a street by street basis. With projections for sea level rise to be between 2 ft and 8 ft by the year 2100, steps need to be taken now to mitigate the impact of these rising waters. The mapping of storm tide pathways is one method that can help predict where waters may flow during a storm and can also be used to plan ahead for sea level rise.
For more information on Storm Tide Pathways visit: https://coastalstudies.org/marine-geology-2/storm-tide-pathways/ and to view the online interactive map go to stormtides.org.