Port Mansfield, TX Coastal Erosion Rate
What USGS measures 12.1 miles southeast of Port Mansfield, TX
The coast 12.1 miles southeast of Port Mansfield, TX has been retreating at a measured 1.99 feet a year, USGS's own long-term rate for this stretch, built from historical shoreline positions rather than a single survey. At that rate, the shoreline has lost roughly 19.9 feet over the last decade.
The grain of this number
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 Port Mansfield, TX. Centered near 26.48°N, 97.27°W. 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.
25 years at this rate
If 1.99 ft/yr holds for the next 25 years, the coast 12.1 miles southeast of Port Mansfield, TX would retreat roughly 50 more feet, a projection, not a certainty: erosion rates shift with storms, sediment supply and any armoring built in the meantime.
What backs this reading up
This reading comes from 41 individual transects averaged together, 100% of which measured erosion rather than growth. The published margin on this reading runs ±1.34 ft/yr. Sorted from fastest erosion to fastest growth across all 1211 measured segments nationally, this one lands at 137. Source: USGS Open-File Report 2004-1089. Bolivar Peninsula, TX sits at national rank 165 for erosion (1.41 ft/yr), one reference point among the 1211 scored segments, 277 miles from here. 1.9 miles up the coast, Port Mansfield, TX shows 1.53 ft/yr of eroding.
Port Mansfield, TX on the source map: try the Coastal Change Hazards Portal, zoomable well past this page's ~3.5-mile grain.