We had one cellular phone for the administrative staff and custodial staff to use for emergencies, but there was a great deal of cellular phone use during the crisis and it was difficult to get calls in and out of the system. It's very awkward to have administrative staff incommunicado when major discussions need to be made constantly. I would also add to the disaster plan instructions about how to divide up the cleanup work and who supervises what areas. Each department should be assigned a specific area to take care of. Of course, each disaster will be different, and there will always need to be regrouping and reassigning when it occurs.
Communication is crucial.
If your disaster is water related, be sure to keep on top of the humidity levels in your building. Even if materials are not actually wet, you can get a lot of damage to the building structure and contents quickly from high humidity. We saw lots of mold and mildew problems in the state aggravated by the power outages which left most people without air conditioning. We engaged an excellent company to dehumidify the building while we were pumping out water. The only flood-damaged materials we had were those already checked out during the crisis.