I am not going to dwell on the aftermath of Hurricane Katrina too much. Unless you've been hiding in a cave somewhere, I don't see how anyone could not have at least an idea of what went on with all the media coverage. It is, however, a good case study on leadership, or the lack of it, at many different levels.
Only you know your leadership situation. Whether you are the chief of police or an officer on the beat, you should know your area of responsibility and what is required of you when the "big one" hits, whatever that catastrophe may be. For those in law enforcement, one of the first considerations must be making sure your family is prepared to function without you, because you need to be at work! There have been reports that up to 500 officers did not report for duty after the Hurricane Katrina for various reasons.
Every officer should have a "call out" box or bag that is always kept in your personal vehicle. Mine contains clothes, extra shoes, toiletries, MREs (meals ready to eat), water, extra ammo, a knife, and a flashlight. I also have a light sleeping bag in the back. If you keep a locker at work, then you should have an extra uniform, vest, and at least tactical gear at home in the event you are at home when a major crisis hits and you cannot make it to the station. You can always call in and then go to the nearest jurisdiction's station to help out until you can get to your assigned area.
About a year ago, I handed out to officers an earthquake preparedness guide in roll call. It had been put together by a lieutenant and included lists of equipment to keep on hand, advice on preparing your family, and important department policy in the event of a major disaster. I recommend that someone at your department or organization take charge and do something similar in order to prepare the troops.
If you are a supervisor, you are remiss if you haven't read through your department's standing plans for emergencies, whether man-made or natural. Keep checklists in your trunks and think about what other gear you might need. I keep maps, a command board, a white board, and dry erase markers, among other things in my trunk. Magnets come in handy to hold things down on the hood or trunk when using your vehicle as a mobile command post.