Casmalia, CA Coastal Erosion Rate
Shoreline change 5.5 miles southwest of Casmalia, CA
5.5 miles southwest of Casmalia, 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 "Casmalia" means on this page
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 Casmalia, CA. Centered near 34.81°N, 120.62°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.
How solid is this number
This reading comes from 86 individual transects averaged together, 84% of which measured erosion rather than growth. USGS's confidence interval here is ±0.4 ft/yr. Taken at face value, this segment's raw -0.36 ft/yr reading would land it 369 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. For scale: Mexico Beach, FL, 2075 miles away, ranks 1046 of 1211 nationally for growth, 0.6 ft/yr. 1.8 miles away, Casmalia, CA is the nearest other measured stretch: also no significant trend.
One address near Casmalia: the Coastal Change Hazards Portal zooms past this stretch to the underlying map.