Grover Beach, CA Coastal Erosion Rate
What USGS measures 1.7 miles northwest of Grover Beach, CA
Good news, and an honest one: USGS's data can't distinguish this stretch, 1.7 miles northwest of Grover Beach, CA, 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 Grover Beach, CA, rather than showing one arbitrary line. Segment center: 35.14, -120.64. Survey years: 1852-2016, method LRR, from USGS's California 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.
Where this fits nationally
This reading comes from 55 individual transects averaged together, 13% of which measured erosion rather than growth. Uncertainty on this specific number: 0.53 ft/yr either side. The unadjusted figure here, 0.18 ft/yr, would place it 914 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 National Shoreline Change data release (ScienceBase, DOI 10.5066/P94J0K7Z), Kratzmann 2024 / Data Report 1187. For scale: Dover Beaches South, NJ, 2543 miles away, ranks 994 of 1211 nationally for growth, 0.4 ft/yr. 2.6 miles up the coast, Oceano, CA shows the same lack of a significant trend.
Not this whole stretch, just Grover Beach itself: the Coastal Change Hazards Portal is USGS's own live version of this data.