Point Arena, CA Coastal Erosion Rate
Shoreline change 0.9 miles south of Point Arena, CA
0.23 feet a year: that is the measured retreat rate USGS's transects show for the coast 0.9 miles south of Point Arena, CA, averaged across the full historical record surveyed here. At that rate, the shoreline has lost roughly 2.3 feet over the last decade.
What "Point Arena" means on this page
Nothing here is parcel-level. USGS's raw transects run every few hundred feet along the shore; this page averages the ones nearest Point Arena, CA into one ~3.5-mile reading rather than picking a single arbitrary line to represent the area. Centered near 38.90°N, 123.70°W. 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.
25 years at this rate
If 0.23 ft/yr holds for the next 25 years, the coast 0.9 miles south of Point Arena, CA would retreat roughly 6 more feet, a projection, not a certainty: erosion rates shift with storms, sediment supply and any armoring built in the meantime.
How solid is this number
74 transects feed this segment's number; 99% of them individually measured retreat. USGS's confidence interval here is ±0.13 ft/yr. Among the 1211 US coastal segments with a measurable trend, this one ranks 472 for erosion, 1 being the fastest-retreating coast in the dataset. Source: USGS National Shoreline Change data release (ScienceBase, DOI 10.5066/P94J0K7Z), Kratzmann 2024 / Data Report 1187. Rank 394 nationally for erosion belongs to Vandenberg AFB, CA, 335 miles from this stretch, measured at 0.33 ft/yr, 1.4x this stretch's rate. Point Arena, CA, 2 miles off, is the adjacent measured stretch, itself no significant trend.
One address near Point Arena: the Coastal Change Hazards Portal zooms past this stretch to the underlying map.