The devastation of New Orleans was a disaster waiting to happen.
The city is artificial and depends on man made embankments to maintain river and lake levels above the city, along with continuous pumped drainage to dispose of sewage and storm water.
This is not risk free as it depends on constant maintenance, the cost of which will continue to rise as older sections need reconstruction. There is also the risk that essential works might be deferred for budgetry reasons.
A prudent policy would have been to put a stop to development in the low areas and gradually abandon such projects - or at least change their use to activities that can easily recover from flooding.
New development of the city would then have only been permitted in areas above the river level.
Similar catastrophes have happened in the past in Holland and at Canvey Island in the UK. In this case, the hurricane was the initiator, but sustained, heavy rainfall elsewhere in the catchment area could have a similar result.
Chris O'Hanlon, chris.ohanlon1@kolumbus. fi, Hakunintie 31, 12100 Oitti, Finland