San Diego, CA Coastal Erosion Rate
What USGS measures 8.4 miles west of San Diego, CA
8.4 miles west of San Diego, CA: USGS's transects didn't pick up a trend here that beats the survey's own uncertainty. That's the majority case nationally, and for this stretch specifically it means the coast is holding, not that the data failed to find anything.
What this reading actually covers
This is a roughly 3.5-mile stretch of coast, not one address or parcel - USGS's own transects run every few hundred feet, but that's finer than any one property needs, so this page reports the stretch nearest San Diego, CA. Centered near 32.79°N, 117.26°W. 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
86 transects feed this segment's number; 22% of them individually measured retreat. USGS's confidence interval here is ±0.27 ft/yr. Taken at face value, this segment's raw 0.13 ft/yr reading would land it 880 of 1211 nationally - a number worth ignoring, since it's statistical noise rather than a real trend. Source: USGS National Shoreline Change data release (ScienceBase, DOI 10.5066/P94J0K7Z), Kratzmann 2024 / Data Report 1187. Longport, NJ sits at national rank 1168 for growth (2.33 ft/yr), one reference point among the 1211 scored segments, 2405 miles from here. San Diego, CA, 2.3 miles off, is the adjacent measured stretch, itself no significant trend.
Not this whole stretch, just San Diego itself: the Coastal Change Hazards Portal is USGS's own live version of this data.