[ardecila]

The new hospital buildings will all be on pilings, but subsidence would damage parking lots and at least some of the ground was likely to drop as much as 30 inches, Rish said.

“We didn’t feel like reconstructing parking lots a year after it was done,” he said.

So a year’s worth of subsidence is being compressed into months.

To do that, 83,000 wicks of felt-like geotextile around a plastic tube — about one for every two square yards of land — are being poked into the 34-acre site by machines called “wick stickers.” Then so much river sand is dumped on top that its weight squeezes water out of the soil, pushing it up through the 42-foot-long wicks and into surface drains that carry the water to collection points and an offsite drainage area.

“We’re utilizing approximately 45 to 50 truckloads of sand per day,” and expect to use a total of 300,000 cubic yards, Rish said. That would fill the U.S. Capitol Rotunda twice. Sand will be moved from place to place on the site as the work continues, Rish said.

The contractor monitors instruments that indicate when enough water has been pushed out and the ground is dense enough, Rish said.

What a massive effort. I'm sure it's insanely expensive, but I wish we did more of this in New Orleans, especially on streets.