Urban Honolulu, HI Coastal Erosion Rate
Is the coast eroding 2.6 miles southwest of Urban Honolulu, HI?
The coast 2.6 miles southwest of Urban Honolulu, HI shows no statistically significant trend either way. USGS's transects measured a rate here, but it's smaller than the survey's own margin of error for this stretch, so calling it "eroding" or "growing" would overstate what the data actually shows.
What "Urban Honolulu" means on this page
Nothing here is parcel-level. USGS's raw transects run every few hundred feet along the shore; this page averages the ones nearest Urban Honolulu, HI into one ~3.5-mile reading rather than picking a single arbitrary line to represent the area. Centered near 21.30°N, 157.88°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 27 individual transects averaged together, 33% of which measured erosion rather than growth. The published margin on this reading runs ±0.19 ft/yr. Taken at face value, this segment's raw 0.14 ft/yr reading would land it 886 of 1211 nationally - a number worth ignoring, since it's statistical noise rather than a real trend. Source: USGS Open-File Report 2011-1009. Manhattan Beach, CA sits at national rank 1040 for growth (0.58 ft/yr), one reference point among the 1211 scored segments, 2550 miles from here. 2.8 miles up the coast, Urban Honolulu, HI shows the same lack of a significant trend.
One address near Urban Honolulu: the Coastal Change Hazards Portal zooms past this stretch to the underlying map.