Vineyard Haven, MA Coastal Erosion Rate
Is the coast eroding 13.7 miles southwest of Vineyard Haven, MA?
Averaged across every transect USGS ran 13.7 miles southwest of Vineyard Haven, MA, the shoreline has been moving inland at 1.14 feet a year, a real measured rate, not a regional estimate applied to this stretch. At that rate, the shoreline has lost roughly 11.4 feet over the last decade.
What "Vineyard Haven" means on this page
Vineyard Haven, MA is the nearest named place, 13.7 miles away, to a ~3.5-mile stretch of coast USGS has surveyed - the reading below covers that whole stretch, not a single property in it. Segment center: 41.31, -70.79. The survey behind it runs to 2007-2009, in USGS's New England / Mid-Atlantic assessment, using the LRR method. Shoreline surveys aren't repeated every year, so this is the most recent long-term measurement USGS has published for this coast, not a live reading.
What 1.14 ft/yr means over time
Run 13.7 miles southwest of Vineyard Haven, MA's 1.14 ft/yr rate forward 25 years and it implies about 28 feet of further retreat, assuming nothing changes, which is exactly the assumption a seawall or nourishment project exists to break.
What backs this reading up
This reading comes from 77 individual transects averaged together, 100% of which measured erosion rather than growth. Uncertainty on this specific number: 0.25 ft/yr either side. Sorted from fastest erosion to fastest growth across all 1211 measured segments nationally, this one lands at 189. Source: USGS Open-File Report 2010-1119. For scale: Dulac, LA, 1400 miles away, ranks 34 of 1211 nationally for erosion, 7.19 ft/yr, 6.3x this stretch's rate. Vineyard Haven, MA, 0.9 miles off, is the adjacent measured stretch, itself no significant trend.
Vineyard Haven, MA on the source map: try the Coastal Change Hazards Portal, zoomable well past this page's ~3.5-mile grain.