Haena, HI Coastal Erosion Rate
Is the coast eroding 0.5 miles north of Haena, HI?
0.5 miles north of Haena, HI: USGS's transects didn't pick up a trend here that beats the survey's own uncertainty. That's the majority case nationally, and for this stretch specifically it means the coast is holding, not that the data failed to find anything.
What "Haena" 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 Haena, HI. Centered near 22.23°N, 159.56°W. 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.
How solid is this number
15 transects feed this segment's number; 100% of them individually measured retreat. Uncertainty on this specific number: 0.4 ft/yr either side. Taken at face value, this segment's raw -0.4 ft/yr reading would land it 352 of 1211 nationally - a number worth ignoring, since it's statistical noise rather than a real trend. Source: USGS Open-File Report 2011-1009. Rank 1161 nationally for growth belongs to Tiki Island, TX, 4011 miles from this stretch, measured at 2.15 ft/yr. Haena, HI, 0.5 miles off, is the adjacent measured stretch, itself no significant trend.
One address near Haena: the Coastal Change Hazards Portal zooms past this stretch to the underlying map.