Catastrophes like Hurricane Katrina are often remembered by a few enduring images. One of them may well be the widely circulated photo of a New Orleans cop, wading through chest high water with an empty gas can, looking for fuel for an emergency generator.
It's unfortunate that we tend not to think very much about worst case scenarios unless we see one somewhere, but it is as good a time as any to review your region's disaster recovery plans, especially with respect to telecommunications.
With most of New Orleans flooded, wireline communications (phone, cable, Internet) are not working. Most wireless Internet systems (e.g. WiFi hotspots) are also out, because electric power and the wired Internet connections that feed them are out.
Most cellphone towers are also out. The towers and antennas are designed to withstand hurricane force winds, but the equipment at the base of the tower is vulnerable to flooding. Based on some reports I have read and heard, many institutions that had invested in backup generators and that had made emergency plans were in trouble because they placed the generators on the ground. With three to six feet of water in the city, the generators are flooded.
It is, of course, much more expensive to place a generator and fuel supplies on an upper floor of a building, but if flooding is a possibility, it needs to be considered. And in a place like New Orleans, which is several feet below sea level, it's hard to understand how the possibility of flooding might not have been considered in disaster planning. A major evacuation of New Orleans hospitals is underway because their generators flooded.
Another often overlooked issue is off-site backups. Many organizations back up data and organizational information to tape or another computer--in the same building. If there is a fire or a flood, the backups will likely be damaged or missing. One of the major long term issues for New Orleans area businesses will be how to restart their businesses in a location outside the main city, while possibly waiting weeks to get back into their New Orleans office spaces and homes.
If you have a full set of backup data for your business or organization, it's straightforward to restart operations in another location--you have your files, customer data, accounting information, etc. and can, with some effort, be up and running relatively quickly.
For organizations with tens or hundreds of employees, a good disaster recovery plan would include a "need to buy" list that has already been itemized and costed out, along with potential suppliers, so that you don't have do this under stress. That list, properly prepared, makes it relatively easy to send employees to even a Best Buy or other electronics retailer and quickly get essential equipment.