Engineers to Test Flood Defenses In New Orleans

NEW ORLEANS -- A $3 million experiment by the Army Corps of Engineers this week will simulate the conditions that caused critical levee failures during Hurricane Katrina, leading to disastrous flooding.

In the test, engineers will gradually pump water into a section of the London Avenue Canal, one of two canals whose flood walls toppled in the storm two years ago, allowing in most of the inundation in the main part of the city.

As the canal waters rise, engineers will monitor the amount of seepage beneath the flood wall and how much the structure tilts -- while promising nervous neighbors that the test will not cause another breach. The measurements will tell them how much rising water the canal wall can withstand.

Some computations show the wall is going to fail at certain water levels; some show it won't," said Ray Martin, a geotechnical engineer consulting with the Corps on the project. "This experiment will let us know."

The fact that such an experiment is necessary two years after the storm reflects the continuing uncertainty as to exactly what caused the city's flood defenses to fail.