Kalaheo, HI Coastal Erosion Rate
What USGS measures 2.6 miles southwest of Kalaheo, HI
2.6 miles southwest of Kalaheo, 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 this reading actually covers
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 Kalaheo, HI. Centered near 21.89°N, 159.55°W. 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.
How solid is this number
This reading comes from 20 individual transects averaged together, 60% of which measured erosion rather than growth. The published margin on this reading runs ±0.28 ft/yr. Taken at face value, this segment's raw -0.05 ft/yr reading would land it 712 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 1035 nationally for growth belongs to Port St. Joe, FL, 4567 miles from this stretch, measured at 0.56 ft/yr. 3 miles away, Lawai, HI is the nearest other measured stretch: also no significant trend.
Kalaheo, HI on the source map: try the Coastal Change Hazards Portal, zoomable well past this page's ~3.5-mile grain.