I have an interest in such things as I worked on some construction projects in the early eighties, flood defences downstream of the Thames Barrier and in the estuary. I watched a reality telly prog a few years ago, where people had to make decisions on defending that Lunnen during an imaginary super flood with the barrier shut. Some of the decisions could have resulted in the decision maker being done for manslaughter if they got it wrong and loads of people got drowned. I guess "they" have all the decisions worked out in advance in real life.