Work on New Orleans Levees Still Not Complete As Gustav Strikes

A multi-billion dollar effort to reinforce New Orleans' flood defenses has been fraught with challenges, controversy and logistical obstacles since Hurricane Katrina engulfed the city three years ago.

Congress authorized $15bn of funding to upgrade New Orleans' entire 350-mile levee system by 2011 to make it capable of withstanding storms of a magnitude expected only once in every 100 years.

But only a quarter of the work has been completed and the US Army Corps of Engineers admitted over the weekend that the city remained at risk.

"It all depends on the strength of the storm in terms of wind speed, water surge and how fast the hurricane tracks," major general Don Riley, deputy chief of the corps, said. "There are still vulnerabilities. There are gaps in the system."

About 150 miles of levees damaged or destroyed by Hurricane Katrina have been repaired and a further 70 miles of the barriers have been improved, typically to a height of 17 feet rather than 14 feet, armored with concrete at the top.

But homeowners living near levees have fought efforts to remove vegetation and officials have encountered difficulties in getting hold of millions of dollars of cubic yards worth of clay to shore up the earthen mounds.

Gerry Galloway, an expert in flood defenses at the University of Maryland, said: "If they get through this one, they're very lucky. Work is still in progress. It's a long way from complete and it's a long way from 100-year storm protection."

At gates where canals meet Lake Pontchartrain, huge pumps have been installed to handle spillages. Concrete splash areas have been installed around the outside of levees to prevent an accumulation of water which, in 2005, began to undermine the structures' foundations and contributed to their collapse.

In May, officials working for Louisiana's governor, Bobby Jindal, expressed concern that the engineering corps may not finish the work on time.

In some quarters, experts have argued that an even greater level of protection is needed, pointing out that the Netherlands' dykes offer protection against weather, which may only be expected once in a millennium.

About 10,000 residents are thought to have ignored warnings and remained in New Orleans as Hurricane Gustav struck the coast of Louisiana.

The state of Louisiana has mobilized 1,500 national guardsmen to secure the city and protect property, and requested additional battalions from nearby Kentucky and Tennessee. New Orleans' mayor, Ray Nagan, has warned that anybody caught looting will go directly to jail.

Evacuated residents will be allowed to begin returning to New Orleans within 24 to 36 hours of the end of the storm, Nagan said today, which could mean people trickling back as early as Tuesday evening. Teams of electricity workers will be shuttled in to restore power.

But Nagan said roads would first need to be cleared of debris and power lines. Those who left in their own cars will be permitted to drive back before buses begin to ferry as many as 18,000 assisted refugees back into the city.