Barnegat Light, NJ Coastal Erosion Rate
What USGS measures 3.4 miles north of Barnegat Light, NJ
USGS's shoreline-change data puts this stretch, 3.4 miles north of Barnegat Light, NJ, at 0.92 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 9.2 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 Barnegat Light, NJ, rather than showing one arbitrary line. Segment center: 39.80, -74.11. Survey years: 2007-2009, method LRR, from USGS's New England / Mid-Atlantic shoreline-change assessment. That's how current the data is here, real, but not a live feed, since a shoreline survey is a major undertaking, not an annual check-in.
What 0.92 ft/yr means over time
Run 3.4 miles north of Barnegat Light, NJ's 0.92 ft/yr rate forward 25 years and it implies about 23 feet of further retreat, assuming nothing changes, which is exactly the assumption a seawall or nourishment project exists to break.
Where this fits nationally
112 transects feed this segment's number; 95% of them individually measured retreat. Uncertainty on this specific number: 0.64 ft/yr either side. Sorted from fastest erosion to fastest growth across all 1211 measured segments nationally, this one lands at 209. Source: USGS Open-File Report 2010-1119. For scale: Port O'Connor, TX, 1490 miles away, ranks 88 of 1211 nationally for erosion, 3.29 ft/yr, 3.6x this stretch's rate. 3.1 miles away, Barnegat Light, NJ is the nearest other measured stretch: also no significant trend.
Barnegat Light, NJ on the source map: try the Coastal Change Hazards Portal, zoomable well past this page's ~3.5-mile grain.