As Gustav rolls ashore near New Orleans, there is one area of the Gulf Coast city that appears to be in danger.

New Orleans Mayor Ray Nagin warned that levees to the west of the city and along the Harbor Canal were at particular risk, saying the west bank levees have not been "armored to the levels of the east bank levees."

The center of the storm is expected to hit about 80 miles southwest of the city.

Army Corps of Engineers officials are monitoring water levels throughout the city, and especially the Inner Harbor Navigation Canal, a waterway that is often referred to as the “Achilles heel” of the system.

Neighborhoods on the west end of town near the Harbor Canal were also believed to be at risk because of high water levels.