Muir Beach, CA Coastal Erosion Rate
Shoreline change right at Muir Beach, CA
0.48 feet a year: that is the measured retreat rate USGS's transects show for the coast right at Muir Beach, CA, averaged across the full historical record surveyed here. At that rate, the shoreline has lost roughly 4.8 feet over the last decade.
What "Muir Beach" 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 Muir Beach, CA into one ~3.5-mile reading rather than picking a single arbitrary line to represent the area. Centered near 37.86°N, 122.58°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.
25 years at this rate
If 0.48 ft/yr holds for the next 25 years, the coast right at Muir Beach, CA would retreat roughly 12 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
This reading comes from 10 individual transects averaged together, 100% of which measured erosion rather than growth. USGS's confidence interval here is ±0.23 ft/yr. This segment ranks 305 of 1211 measured US coastal segments, ordered from fastest erosion to fastest growth. Source: USGS National Shoreline Change data release (ScienceBase, DOI 10.5066/P94J0K7Z), Kratzmann 2024 / Data Report 1187. West Hampton Dunes, NY sits at national rank 313 for erosion (0.46 ft/yr), one reference point among the 1211 scored segments, 2638 miles from here. 2.8 miles away, Muir Beach, CA is the nearest other measured stretch: also no significant trend.
Not this whole stretch, just Muir Beach itself: the Coastal Change Hazards Portal is USGS's own live version of this data.