Matagorda, TX Coastal Erosion Rate
What USGS measures 10.7 miles southwest of Matagorda, TX
USGS's shoreline-change data puts this stretch, 10.7 miles southwest of Matagorda, TX, at 0.75 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 7.5 feet over the last decade.
What "Matagorda" 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 Matagorda, TX, rather than showing one arbitrary line. Segment center: 28.58, -96.08. 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 0.75 ft/yr means over time
Run 10.7 miles southwest of Matagorda, TX's 0.75 ft/yr rate forward 25 years and it implies about 19 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
Averaging 23 separate transects produced this segment's rate, with 100% individually reading as erosion, rather than relying on any single survey line. Uncertainty on this specific number: 0.49 ft/yr either side. This segment ranks 235 of 1211 measured US coastal segments, ordered from fastest erosion to fastest growth. Source: USGS Open-File Report 2004-1089. Rank 98 nationally for erosion belongs to South Padre Island, TX, 175 miles from this stretch, measured at 2.9 ft/yr, 3.9x this stretch's rate. 1.7 miles away, Matagorda, TX is the nearest other measured stretch: slight erosion at 0.54 ft/yr.
Matagorda, TX on the source map: try the Coastal Change Hazards Portal, zoomable well past this page's ~3.5-mile grain.