The big stink in the media right now is that it appears that the
levees will be rebuilt more or less the way they were before Katrina.

What I don't get this. The canals are long and thin. It's very
expensive to construct levee walls that will stay up during high water
/ high wind events. Why not build a gate system at both ends of these
canals to basically shut them during a hurricane? With the canals
blocked off, even if the levee walls fail, the damage would be limited
to the (relatively small?) amount of water in the canals.

Weather Man wrote:
The big stink in the media right now is that it appears that the
levees will be rebuilt more or less the way they were before Katrina.

With George Bush in charge you aught to consider yourselves lucky they
are not talking about reinstituting slavery to pay for it all.

What I don't get this. The canals are long and thin. It's very
expensive to construct levee walls that will stay up during high water
/ high wind events. Why not build a gate system at both ends of these
canals to basically shut them during a hurricane? With the canals
blocked off, even if the levee walls fail, the damage would be limited
to the (relatively small?) amount of water in the canals.

The problem is that the Misisippi is also thin and bloody long. How are
you going to stop all that? An hurricane is basically a lenticular
cloud some 300 miles wide. Once the sea is crossed there is no more
incoming water.

It's too low and too heavy to dissipate, so where is going to go?

Besides, when it's all over, the states hit have to pay for the repairs
anyway so it's no big deal if congress or whatever cuts the funding
again.