St. George Island, FL Coastal Erosion Rate
What USGS measures 6 miles west of St. George Island, FL
USGS's shoreline-change data puts this stretch, 6 miles west of St. George Island, FL, at 1.37 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 13.7 feet over the last decade.
What "St. George Island" 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 St. George Island, FL, rather than showing one arbitrary line. Segment center: 29.63, -84.99. Survey years: 2001, method LRR, from USGS's Gulf of Mexico 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.
What 1.37 ft/yr means over time
Run 6 miles west of St. George Island, FL's 1.37 ft/yr rate forward 25 years and it implies about 34 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
Averaging 52 separate transects produced this segment's rate, with 98% individually reading as erosion, rather than relying on any single survey line. USGS's confidence interval here is ±0.29 ft/yr. This segment ranks 170 of 1211 measured US coastal segments, ordered from fastest erosion to fastest growth. Source: USGS Open-File Report 2004-1089. For scale: Port Mansfield, TX, 780 miles away, ranks 118 of 1211 nationally for erosion, 2.26 ft/yr, 1.6x this stretch's rate. 1.8 miles up the coast, Apalachicola, FL shows 0.98 ft/yr of eroding.
Not this whole stretch, just St. George Island itself: the Coastal Change Hazards Portal is USGS's own live version of this data.