Narragansett Pier, RI Coastal Erosion Rate
Is the coast eroding 4.2 miles south of Narragansett Pier, RI?
USGS's shoreline-change data puts this stretch, 4.2 miles south of Narragansett Pier, RI, at 0.11 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 1.1 feet over the last decade.
What "Narragansett Pier" means on this page
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 Narragansett Pier, RI, rather than showing one arbitrary line. Segment center: 41.37, -71.49. USGS's New England / Mid-Atlantic assessment last surveyed this stretch through 2007-2009, computing the rate with its LRR method. Other US regions were surveyed in different years, sometimes decades apart, so this page states its own rather than implying one national vintage.
What 0.11 ft/yr means over time
Run 4.2 miles south of Narragansett Pier, RI's 0.11 ft/yr rate forward 25 years and it implies about 3 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
64 transects feed this segment's number; 77% of them individually measured retreat. Uncertainty on this specific number: 0.08 ft/yr either side. Sorted from fastest erosion to fastest growth across all 1211 measured segments nationally, this one lands at 633. Source: USGS Open-File Report 2010-1119. Virginia Beach, VA sits at national rank 206 for erosion (0.93 ft/yr), one reference point among the 1211 scored segments, 404 miles from here. 1 miles away, Narragansett Pier, RI is the nearest other measured stretch: also no significant trend.
Narragansett Pier, RI on the source map: try the Coastal Change Hazards Portal, zoomable well past this page's ~3.5-mile grain.