Mokuleia, HI Coastal Erosion Rate
What USGS measures 3.7 miles west of Mokuleia, HI
USGS's shoreline-change data puts this stretch, 3.7 miles west of Mokuleia, HI, at 0.33 feet of erosion a year on average, a long-term rate for this specific ~3.5-mile section, not one storm's damage. At that rate, the shoreline has lost roughly 3.3 feet over the last decade.
What this reading actually covers
USGS surveys the coast in transects spaced a few hundred feet apart; this page groups the nearest ones into a single ~3.5-mile reading for the stretch closest to Mokuleia, HI, rather than showing one arbitrary line. Segment center: 21.58, -158.23. Survey years: 2007-2010, method WLR, from USGS's Hawaii 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.
What 0.33 ft/yr means over time
Run 3.7 miles west of Mokuleia, HI's 0.33 ft/yr rate forward 25 years and it implies about 8 feet of further retreat, assuming nothing changes, which is exactly the assumption a seawall or nourishment project exists to break.
Where this fits nationally
Averaging 50 separate transects produced this segment's rate, with 100% individually reading as erosion, rather than relying on any single survey line. Uncertainty on this specific number: 0.17 ft/yr either side. Sorted from fastest erosion to fastest growth across all 1211 measured segments nationally, this one lands at 393. Source: USGS Open-File Report 2011-1009. For scale: Gulf Park Estates, MS, 4288 miles away, ranks 42 of 1211 nationally for erosion, 6.04 ft/yr, many times over this stretch's own rate. 1.9 miles up the coast, Mokuleia, HI shows 0.13 ft/yr of eroding.
Mokuleia, HI on the source map: try the Coastal Change Hazards Portal, zoomable well past this page's ~3.5-mile grain.