Dulac, LA Coastal Erosion Rate
Is the coast eroding 27 miles southwest of Dulac, LA?
27 miles southwest of Dulac, LA: USGS's transects didn't pick up a trend here that beats the survey's own uncertainty. That's the majority case nationally, and for this stretch specifically it means the coast is holding, not that the data failed to find anything.
What "Dulac" means on this page
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 Dulac, LA. Centered near 29.08°N, 90.94°W. 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.
How solid is this number
This reading comes from 9 individual transects averaged together, 100% of which measured erosion rather than growth. USGS's confidence interval here is ±15.7 ft/yr. Taken at face value, this segment's raw -4.19 ft/yr reading would land it 69 of 1211 nationally - a number worth ignoring, since it's statistical noise rather than a real trend. Source: USGS Open-File Report 2004-1089. Oak Beach, NY sits at national rank 1189 for growth (3.79 ft/yr), one reference point among the 1211 scored segments, 1276 miles from here. Dulac, LA, 0.7 miles off, is the adjacent measured stretch, itself no significant trend.
Not this whole stretch, just Dulac itself: the Coastal Change Hazards Portal is USGS's own live version of this data.