Paia, HI Coastal Erosion Rate
Shoreline change 1.5 miles north of Paia, HI
Good news, and an honest one: USGS's data can't distinguish this stretch, 1.5 miles north of Paia, HI, from a flat trend. Whatever small movement it measured here is statistical noise, not a reliable direction, so none is claimed.
What "Paia" 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 Paia, HI, rather than showing one arbitrary line. Segment center: 20.93, -156.36. 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.
What backs this reading up
This reading comes from 91 individual transects averaged together, 97% of which measured erosion rather than growth. USGS's confidence interval here is ±0.45 ft/yr. The unadjusted figure here, -0.24 ft/yr, would place it 456 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. Dunes City, OR sits at national rank 1058 for growth (0.67 ft/yr), one reference point among the 1211 scored segments, 2433 miles from here. 0.8 miles up the coast, Paia, HI shows 0.27 ft/yr of eroding.
Paia, HI on the source map: try the Coastal Change Hazards Portal, zoomable well past this page's ~3.5-mile grain.