Emergency management plans that work and have been tested [not just paper-drilled] must be in place LA did drill this, last year. It was called Hurricane Pam and they identified areas that needed improvements.
Info about Hurricane Pam exerciseLSU has a hurricane department that has written papers based on the outcome of this drill (estimated around 60,000 deaths).
Yes it appears they did, but under duress; did not utilize public transportation assets then and did not make corrections today apparently...that's paper drilling your emergency plans if you do not learn lessons and make corrections.