By August 26, the possibility of never-before-happened destruction and damage was already being considered. Some computer models were putting the city of New Orleans right in the center of their track probabilities, and the chances of a direct hit were forecast at 17% (with strike probability rising to 29% by August 28). This scenario was considered a potential disaster because 80% of the New Orleans metropolitan area is below sea level along Lake Pontchartrain. Since the storm surge produced by the hurricane's right-front quadrant (containing the strongest winds) was more than 20 ft (6 m) near Biloxi, emergency management officials in New Orleans feared that the storm surge could go over the tops of levees protecting the city, causing major flooding. This risk of devastation had been known for some time; previous studies by FEMA and the Army Corps of Engineers had warned that a direct hurricane strike on New Orleans could lead to massive flooding, which would lead to thousands of drowning deaths, as well as many more suffering from disease and dehydration, as the flood waters slowly retreated from the city.