Port O'Connor, TX Coastal Erosion Rate
What USGS measures 3.3 miles southeast of Port O'Connor, TX
Averaged across every transect USGS ran 3.3 miles southeast of Port O'Connor, TX, the shoreline has been moving inland at 3.02 feet a year, a real measured rate, not a regional estimate applied to this stretch. At that rate, the shoreline has lost roughly 30.2 feet over the last decade.
The grain of this number
Port O'Connor, TX is the nearest named place, 3.3 miles away, to a ~3.5-mile stretch of coast USGS has surveyed - the reading below covers that whole stretch, not a single property in it. Segment center: 28.41, -96.38. The survey behind it runs to 2001, in USGS's Gulf of Mexico assessment, using the LRR 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.
What 3.02 ft/yr means over time
Run 3.3 miles southeast of Port O'Connor, TX's 3.02 ft/yr rate forward 25 years and it implies about 76 feet of further retreat, assuming nothing changes, which is exactly the assumption a seawall or nourishment project exists to break.
What backs this reading up
20 transects feed this segment's number; 100% of them individually measured retreat. The published margin on this reading runs ±2.95 ft/yr. This segment ranks 94 of 1211 measured US coastal segments, ordered from fastest erosion to fastest growth. Source: USGS Open-File Report 2004-1089. Rank 133 nationally for erosion belongs to Modest Town, VA, 1368 miles from this stretch, measured at 2.05 ft/yr, 0.7x this stretch's rate. Port O'Connor, TX, 0.8 miles off, is the adjacent measured stretch, reading severe erosion at 3.29 ft/yr.
Port O'Connor, TX on the source map: try the Coastal Change Hazards Portal, zoomable well past this page's ~3.5-mile grain.