The pictures of water lapping over the Industrial Canal Levee in New Orleans look ominous. However, according to UC Davis levee expert Jeffrey Mount, what they really show is a levee working as it should.
"If designed well, levees can take over-topping. That is water over the top and running down the inside, and that's to be expected, and that's planned for in New Orleans," said Mount.
According to Mount, it is even OK for levees to spring a few leaks as they have during Hurricane Gustav.
"What people forget is that all levees leak. Water flows through the levees. After all, they're big piles of dirt," said Mount. "If they leak too fast, that's when they fail."
That is what happened in 2005 when Hurricane Katrina put so much pressure on New Orleans' sub-par levees. They failed en masse, flooding 80 percent of the city.
Since then, many of those levees have been repaired to pre-Katrina levels, but a planned upgrade -- a strengthening of the system -- has yet to begin.
For instance, work on the Industrial Levee is not scheduled for completion until 2011.
"Had this been Katrina, we would've seen flooding again in New Orleans… exactly the same," said Mount.
Whatever Gustav's legacy in the Gulf region, levee experts believe the storm should serve as yet another wake-up call to California.
"This will remind us again that we have a long way to go and many billions of dollars to invest in the system to increase our protection," said Mount.
Emergency repairs aside, the levees that currently protect nearly two million people in Sacramento and the Central Valley remain extremely vulnerable -- earthen barriers that in many places are more than 100 years old.