New Orleans flooding caused by 7 inches of sudden, strong rain; pumps working, S&WB says

NOLA.com ^ | July 10, 2019 | Staff report

[PeterPrinciple]

118 of 120 pumps ready and manned so assume are used.

One reference to storm drains being litter clogged, that would overcome a lot of plans...…………………………

You can design a system but there are a lot of factors that can go wrong.

[tomkat]

Subsidence

[OrangeHoof]

Bush’s fault.

Where be mah FEMA trailer?

[Vaquero]

Large portions of Orleans, St. Bernard, and Jefferson parishes are currently below sea level—and continue to sink. New Orleans is built on thousands of feet of soft sand, silt, and clay. Subsidence, or settling of the ground surface, occurs naturally due to the consolidation and oxidation of organic soils (called “marsh” in New Orleans) and local groundwater pumping. In the past, flooding and deposition of sediments from the Mississippi River counterbalanced the natural subsidence, leaving southeast Louisiana at or above sea level. However, due to major flood control structures being built upstream on the Mississippi River and levees being built around New Orleans, fresh layers of sediment are not replenishing the ground lost by subsidence.[70]

[Extremely Extreme Extremist]

Dawg holla at ya boy!

[Elsie]

...how does the land sink?

By sucking the OIL out of the ground!

[trebb]

Was there trying to get to Ochsners for an appointment for the wife....Took an hour to go the first 70 miles and 4 hours for the last 15 miles trying to find routes around the flooded areas...saw many cars trying to drive through 3’-4’ water and ending up as “lily pads”...
Had passed through about 1/2” rain showers on way and didn’t realize the true scope of what had happened and what was going on - many streets running like rivers, all underpasses flooded (and most on/off ramps for I-10 are at the level of the underpasses so once the surface streets locked up, I-10 became a parking lot.

[plain talk]

Reminds me of the infamous May 3, 1978 flood or maybe worse. That one took me hours to get home from work.

[grwcfl537]

Many neighborhoods were built on garbage, think landfill. Organic material breaks down and over time subsidence happens.

[tm61]

From what i read, can be caused by how land, or
Seabed , very slowly, for very long time, reacts
From the weight of ice in previous ice age once
It has melted., surface will rise in one area,
And sink in another. Google “chesapeake bay
Sinking”, explanation is detailed there.

[ClearBlueSky]

Thunderstorms can now drown New Orleans. Why is that? When I grew up there in the 60's and 70's the French Quarter and downtown did not flood. High ground did not flood. 40-50 years later EVERYTHING is older, has been through multiple storms and everything is SINKING. The pipes underground are cracked, broken and in some places ancient, inadequate CLAY!
Age matters. What doesn't knock you over at 20 will at 70. It's 300 years old and deteriorating. Add political incompetence and corruption to the mix and New Orleans is- in my local opinion- Unsustainable. It's a city built in a sinking hole. No amount of $$ can fix it. Nature WILL win-but politicians are getting rich insisting money can save it.Locals know better-daily rainstorms prove it. One can only party so long before reality is undeniable.

[trebb]

And it looks like they are in for a 3-day soaking starting today as Barry moves in...I feel for the residents who have to use the medians as “high ground” to park their vehicles and hope the water doesn’t reach them.
We’re over in Gulfport and expected to get more rain and wind but the flooding doesn’t happen in the high density areas over here (except for a Katrina or similar).