Low-lying areas of Memphis, Tenn., have been flooded by the rising Mississippi River, forcing evacuations, but engineers said the city’s levees are holding and it has likely seen the worst of the flooding.

Officials say the river is expected to crest at 48 feet, 14 feet above the flood thresholds, as it passes through western Tennessee. Eleanor Boudreau, a reporter for WKNO in Memphis, describes how the city has reacted to rising waters. The historic levels, estimated early Tuesday morning at 47.85 feet by the National Weather Service, are expected to remain for 24-36 hours before they subside.

In New Orleans, a city still recovering from the effects of Hurricane Katrina, residents are preparing for another deluge, and Louisiana’s farmland could be damaged as the water travels downstream.

The U.S. Army Corps of Engineers has opened a rarely-used spillway near New Orleans to divert some of the water. The Bonnet Carre spillway is designed to push the water away from the city’s levees. Officials are considering the opening of a second major spillway Tuesday. Louisiana Gov. Bobby Jindal has activated 400 National Guard troops to assist in sandbagging and evacuations.