Slidell, LA Coastal Erosion Rate
What USGS measures 56.7 miles east of Slidell, LA
Averaged across every transect USGS ran 56.7 miles east of Slidell, LA, the shoreline has been moving inland at 4.14 feet a year, a real measured rate, not a regional estimate applied to this stretch. At that rate, the shoreline has lost roughly 41.4 feet over the last decade.
What this reading actually covers
Slidell, LA is the nearest named place, 56.7 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: 30.03, -88.88. 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 4.14 ft/yr means over time
Run 56.7 miles east of Slidell, LA's 4.14 ft/yr rate forward 25 years and it implies about 103 feet of further retreat, assuming nothing changes, which is exactly the assumption a seawall or nourishment project exists to break.
Where this fits nationally
This reading comes from 35 individual transects averaged together, 100% of which measured erosion rather than growth. The published margin on this reading runs ±0.89 ft/yr. This segment ranks 70 of 1211 measured US coastal segments, ordered from fastest erosion to fastest growth. Source: USGS Open-File Report 2004-1089. For scale: Goleta, CA, 1834 miles away, ranks 418 of 1211 nationally for erosion, 0.28 ft/yr, a small fraction of this stretch's own rate. 0.6 miles away, Slidell, LA is the nearest other measured stretch: severe erosion at 4.59 ft/yr.
Slidell, LA on the source map: try the Coastal Change Hazards Portal, zoomable well past this page's ~3.5-mile grain.