Lompoc, CA Coastal Erosion Rate
What USGS measures 9.5 miles southwest of Lompoc, CA
USGS's shoreline-change data puts this stretch, 9.5 miles southwest of Lompoc, CA, at 0.3 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 3 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 Lompoc, CA, rather than showing one arbitrary line. Segment center: 34.54, -120.54. The survey behind it runs to 1852-2016, in USGS's California assessment, using the LRR method. Shoreline surveys aren't repeated every year, so this is the most recent long-term measurement USGS has published for this coast, not a live reading.
What 0.3 ft/yr means over time
Run 9.5 miles southwest of Lompoc, CA's 0.3 ft/yr rate forward 25 years and it implies about 8 feet of further retreat, assuming nothing changes, which is exactly the assumption a seawall or nourishment project exists to break.
What backs this reading up
55 transects feed this segment's number; 100% of them individually measured retreat. USGS's confidence interval here is ±0.09 ft/yr. Sorted from fastest erosion to fastest growth across all 1211 measured segments nationally, this one lands at 404. Source: USGS National Shoreline Change data release (ScienceBase, DOI 10.5066/P94J0K7Z), Kratzmann 2024 / Data Report 1187. Rank 418 nationally for erosion belongs to Goleta, CA, 34 miles from this stretch, measured at 0.28 ft/yr, 0.9x this stretch's rate. 1.4 miles up the coast, Lompoc, CA shows the same lack of a significant trend.
Lompoc, CA on the source map: try the Coastal Change Hazards Portal, zoomable well past this page's ~3.5-mile grain.