Dillon Beach, CA Coastal Erosion Rate
Is the coast eroding 0.7 miles west of Dillon Beach, CA?
The coast 0.7 miles west of Dillon Beach, CA shows no statistically significant trend either way. USGS's transects measured a rate here, but it's smaller than the survey's own margin of error for this stretch, so calling it "eroding" or "growing" would overstate what the data actually shows.
The grain of this number
Nothing here is parcel-level. USGS's raw transects run every few hundred feet along the shore; this page averages the ones nearest Dillon Beach, CA into one ~3.5-mile reading rather than picking a single arbitrary line to represent the area. Centered near 38.24°N, 122.97°W. 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.
Where this fits nationally
53 transects feed this segment's number; 11% of them individually measured retreat. Uncertainty on this specific number: 0.66 ft/yr either side. Taken at face value, this segment's raw 0.55 ft/yr reading would land it 1033 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. Rank 1040 nationally for growth belongs to Manhattan Beach, CA, 394 miles from this stretch, measured at 0.58 ft/yr. Dillon Beach, CA, 3.5 miles off, is the adjacent measured stretch, itself no significant trend.
Dillon Beach, CA on the source map: try the Coastal Change Hazards Portal, zoomable well past this page's ~3.5-mile grain.