This is kind of disturbing. A decade after Hurricane Katrina, three separate engineering teams have concluded that the only way to save New Orleans from future hurricane damage by building up the Mississippi Delta around the city is to let the end of the Delta die. And maybe that’s true. The declining sediment load thanks to agriculture combining with the engineering choices already made on the river plus rising sea levels probably does mean that hard choices are going to have to be made. Of course even if scientists, engineers, and urban planners had consensus that this was the best answer, it doesn’t mean the politics would allow it to happen, with the status quo having an endless amount of money behind it.