As if there isn't enough problems with flooding in New Orleans from hurricanes, dikes failing and delta erosion, as pointed out in Are shifts in Earth's crust causing New Orleans to sink? a major deep earth fault under New Orleans may be subsiding causing the area to sink at a faster rate than from all other geological conditions:

New research suggests, however, that at least for nearby Michoud, La., the dominant driver pulling the region under may not be among the usual suspects: oil extraction, pumping groundwater to the surface, or diverting the Mississippi for navigation.

Instead, the King of Slump may be a deep fault that cuts across southeastern Louisiana and under Michoud. During the 1970s, the fault appears to have contributed from 50 to 73 percent of the subsidence in this section of Orleans parish, depending on the time period measured. If sustained over a century, that would equate to as much as a six-foot sea-level rise, independent of any increase tied to global warming.

If this is true, the folly of rebuilding New Orleans on the same site is obvious unless of course it is a city that can float. Otherwise Mayor Naggins chocolate city is destined to become very wet and who likes soggy chocolate?

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