Mokuleia, HI Coastal Erosion Rate
What USGS measures 1.8 miles west of Mokuleia, HI
The coast 1.8 miles west of Mokuleia, HI has been retreating at a measured 0.13 feet a year, USGS's own long-term rate for this stretch, built from historical shoreline positions rather than a single survey. At that rate, the shoreline has lost roughly 1.3 feet over the last decade.
What "Mokuleia" 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 Mokuleia, HI. Centered near 21.58°N, 158.20°W. USGS's Hawaii assessment last surveyed this stretch through 2007-2010, computing the rate with its WLR method. Other US regions were surveyed in different years, sometimes decades apart, so this page states its own rather than implying one national vintage.
25 years at this rate
If 0.13 ft/yr holds for the next 25 years, the coast 1.8 miles west of Mokuleia, HI would retreat roughly 3 more feet, a projection, not a certainty: erosion rates shift with storms, sediment supply and any armoring built in the meantime.
What backs this reading up
This reading comes from 260 individual transects averaged together, 99% of which measured erosion rather than growth. The published margin on this reading runs ±0.11 ft/yr. Sorted from fastest erosion to fastest growth across all 1211 measured segments nationally, this one lands at 605. Source: USGS Open-File Report 2011-1009. Rank 342 nationally for erosion belongs to Sand City, CA, 2408 miles from this stretch, measured at 0.42 ft/yr, 3.2x this stretch's rate. Mokuleia, HI, 1.9 miles off, is the adjacent measured stretch, reading slight erosion at 0.33 ft/yr.
Not this whole stretch, just Mokuleia itself: the Coastal Change Hazards Portal is USGS's own live version of this data.