Puhi, HI Coastal Erosion Rate
Shoreline change 3.8 miles south of Puhi, HI
Good news, and an honest one: USGS's data can't distinguish this stretch, 3.8 miles south of Puhi, HI, from a flat trend. Whatever small movement it measured here is statistical noise, not a reliable direction, so none is claimed.
What "Puhi" means on this page
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 Puhi, HI, rather than showing one arbitrary line. Segment center: 21.91, -159.40. The survey behind it runs to 2007-2010, in USGS's Hawaii assessment, using the WLR 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.
What backs this reading up
Averaging 179 separate transects produced this segment's rate, with 85% individually reading as erosion, rather than relying on any single survey line. The published margin on this reading runs ±0.28 ft/yr. The unadjusted figure here, -0.14 ft/yr, would place it 581 of 1211 if ranked directly - but an unreliable rank isn't a useful one, which is exactly why "no significant trend" is the headline instead. Source: USGS Open-File Report 2011-1009. For scale: Atlantic City, NJ, 5013 miles away, ranks 1137 of 1211 nationally for growth, 1.38 ft/yr. Poipu, HI, 4.2 miles off, is the adjacent measured stretch, reading slight erosion at 0.32 ft/yr.
Not this whole stretch, just Puhi itself: the Coastal Change Hazards Portal is USGS's own live version of this data.