New research has suggested that higher than expected subsidence levels certain areas of New Orleans could have contributed to the collapse of the levee system when Katrina hit last year, according to a report by the BBC.

The study, which was compiled by the University of Miami, is based on satellite data compiled between 2002 and 2005 which show that New Orleans has been sinking quicker than previously thought.

The report recommends that certain low level sectors of New Orleans prove too much of a risk to warrant rebuilding, stating that some areas are sinking by over an inch a year and furthermore that one particular levee has sunk over 3 ft in the thirty years since it was constructed.