Spring Lake, NJ Coastal Erosion Rate
Is the coast eroding 0.5 miles southwest of Spring Lake, NJ?
Good news, and an honest one: USGS's data can't distinguish this stretch, 0.5 miles southwest of Spring Lake, NJ, from a flat trend. Whatever small movement it measured here is statistical noise, not a reliable direction, so none is claimed.
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 Spring Lake, NJ, rather than showing one arbitrary line. Segment center: 40.15, -74.04. 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.
How solid is this number
Averaging 114 separate transects produced this segment's rate, with 31% individually reading as erosion, rather than relying on any single survey line. USGS's confidence interval here is ±0.43 ft/yr. The unadjusted figure here, 0.09 ft/yr, would place it 843 of 1211 if ranked directly - but an unreliable rank isn't a useful one, which is exactly why "no significant trend" is the headline instead. Source: USGS Open-File Report 2010-1119. Rank 1125 nationally for growth belongs to Coronado, CA, 2429 miles from this stretch, measured at 1.22 ft/yr. 2.1 miles away, Belmar, NJ is the nearest other measured stretch: also no significant trend.
Spring Lake, NJ on the source map: try the Coastal Change Hazards Portal, zoomable well past this page's ~3.5-mile grain.