Traffic management for exceptional circumstances

The possibilities of the transport system to detail with exceptional circumstances is becoming more and more important. Exceptional circumstances (large incidents, flooding, earth quakes, terroristic attacks) do not occur often, but have a large social and economic impact. Due to the rare occurences, there is little experience and knowledge on how to deal with these circumstances. A lot of questions still have to be answered. What are good traffic management strategies to reduce the impacts of large incidents and disasters? Which information do we have to provide to the road users? How can we assess these strategies? How can we use knowledge on traffic management for exceptional circumstances for regular traffic conditions?