Apalachicola, FL Coastal Erosion Rate
What USGS measures 7.5 miles south of Apalachicola, FL
USGS's shoreline-change data puts this stretch, 7.5 miles south of Apalachicola, FL, at 0.98 feet of erosion a year on average, a long-term rate for this specific ~3.5-mile section, not one storm's damage. At that rate, the shoreline has lost roughly 9.8 feet over the last decade.
What this reading actually covers
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 Apalachicola, FL, rather than showing one arbitrary line. Segment center: 29.62, -85.02. USGS's Gulf of Mexico assessment last surveyed this stretch through 2001, computing the rate with its LRR 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 0.98 ft/yr means over time
Run 7.5 miles south of Apalachicola, FL's 0.98 ft/yr rate forward 25 years and it implies about 25 feet of further retreat, assuming nothing changes, which is exactly the assumption a seawall or nourishment project exists to break.
How solid is this number
This reading comes from 39 individual transects averaged together, 100% of which measured erosion rather than growth. USGS's confidence interval here is ±0.26 ft/yr. Sorted from fastest erosion to fastest growth across all 1211 measured segments nationally, this one lands at 196. Source: USGS Open-File Report 2004-1089. Rank 71 nationally for erosion belongs to Sargent, TX, 637 miles from this stretch, measured at 4.11 ft/yr, 4.2x this stretch's rate. 1.7 miles away, Apalachicola, FL is the nearest other measured stretch: also no significant trend.
One address near Apalachicola: the Coastal Change Hazards Portal zooms past this stretch to the underlying map.