San Clemente, CA Coastal Erosion Rate
Shoreline change 3.5 miles south of San Clemente, CA
Good news, and an honest one: USGS's data can't distinguish this stretch, 3.5 miles south of San Clemente, CA, from a flat trend. Whatever small movement it measured here is statistical noise, not a reliable direction, so none is claimed.
What "San Clemente" 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 San Clemente, CA, rather than showing one arbitrary line. Segment center: 33.40, -117.60. USGS's California assessment last surveyed this stretch through 1852-2016, 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
This reading comes from 141 individual transects averaged together, 35% of which measured erosion rather than growth. Uncertainty on this specific number: 0.17 ft/yr either side. The unadjusted figure here, 0.06 ft/yr, would place it 828 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: Pacific Beach, WA, 1014 miles away, ranks 1100 of 1211 nationally for growth, 0.95 ft/yr. 2.2 miles away, San Clemente, CA is the nearest other measured stretch: slight erosion at 0.19 ft/yr.
One address near San Clemente: the Coastal Change Hazards Portal zooms past this stretch to the underlying map.