Charlestown, RI Coastal Erosion Rate
Shoreline change 1.9 miles southwest of Charlestown, RI
USGS's shoreline-change data puts this stretch, 1.9 miles southwest of Charlestown, RI, at 0.35 feet of erosion a year on average, a long-term rate for this specific ~3.5-mile section, not one storm's damage. At that rate, the shoreline has lost roughly 3.5 feet over the last decade.
The grain of this number
USGS surveys the coast in transects spaced a few hundred feet apart; this page groups the nearest ones into a single ~3.5-mile reading for the stretch closest to Charlestown, RI, rather than showing one arbitrary line. Segment center: 41.36, -71.65. 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 0.35 ft/yr means over time
Run 1.9 miles southwest of Charlestown, RI's 0.35 ft/yr rate forward 25 years and it implies about 9 feet of further retreat, assuming nothing changes, which is exactly the assumption a seawall or nourishment project exists to break.
Where this fits nationally
87 transects feed this segment's number; 100% of them individually measured retreat. Uncertainty on this specific number: 0.16 ft/yr either side. Among the 1211 US coastal segments with a measurable trend, this one ranks 374 for erosion, 1 being the fastest-retreating coast in the dataset. Source: USGS Open-File Report 2010-1119. Rank 170 nationally for erosion belongs to St. George Island, FL, 1102 miles from this stretch, measured at 1.37 ft/yr, 3.9x this stretch's rate. 2.8 miles away, Quonochontaug, RI is the nearest other measured stretch: slight erosion at 0.29 ft/yr.
Not this whole stretch, just Charlestown itself: the Coastal Change Hazards Portal is USGS's own live version of this data.