re: NOLA is sinking - NASA maps show the rate

Venice, Italy 2.0

From 2008 to 2014 I was involved with the Dutch Dialogues and then the Urban Water Plan. It was a collaboration between Dutch and American designers, scientists, economists, and politicians. I was also involved in the Pontilly Stormwater HMGP and couple dozen other miscellaneous water management projects in Southern Louisiana.

The main culprit to subsidence are the pumps. You can compare Orleans to East Bank Jefferson. Orleans has always kept their pumps running to keep the canals low. What this does is pulls groundwater out of the soil, leading to the breakdown of organic material. Jefferson did not keep their canals low until the mid-80's. After they instituted a pumping regime similar to Orleans, you can start to see the subsidence really increase in areas of East Bank Jefferson.

We did a trial on the Canal St. canal where we closed a flood gate and siphoned water back in from the 17th St canal. What this did is backflood the local drainage pipes, which was cracked all the hell, and essentially created a neighborhood-wide drip irrigation system to recharge groundwater. When we saw a storm approaching, the pumps were turned on to draw down before filling back up with stormwater. Modern forecasting allows us to have dynamic canal levels that can recharge groundwater and also provide flood protection.

Hurricanes and floods are the big and legitimate boogeymans, but subsidence is the sleeper existential threat to New Orleans. The city cannot afford to ignore it. We had very good luck getting administration officials on our side from JP, OP, SWB, ACofE, DPW, NORA, and a bunch of the other major players. Things are on the right track. Once you start showing people dollar amounts, things get real.

I'm a firm believer in climate change, but it has little do with subsidence in the metro area.

Some very good reading on the subject: Living with Water

Interesting project. I know how groundwater affects subsidence, but never thought the pumps affected it that much. We have been pumping sand underneath my grandma's house a lot more over the past 15 years now that I think about it. Used to be every 5 years or so, and now it needs it every two

Depends on where you dig a hole. I've done hundreds of bores across the area. Sometime you hit water at 12 inches. Other times you hit it at 12 feet.

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So people shouldn't have settled there? Who knew? Baffling really.

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The original plan was for New Orleans to be located at the confluence of Bayou Manchac and the Mississippi River at the present-day boundaries of East Baton Rouge and Iberville Parishes.

River to Bayou St. John is a short walk. Bayou St. John from the back of the city to the Lake and then Gulf is also shorter.

The Gentilly road ends near the end of Bayou St. John, as well.

Al Gore: Global warming/climate change causing this too.

Idiot