In the last year or two I have read more than one or two articles on FR - in depth articles, about the exact scenario that has now happened. Not the mayhem created by subhuman scum, but the water damage, and everything that that entails. In detail.
Those who could have done something did indeed know exactly what would happen, and they did not plan properly. To put it very mildly.
Planning could have been better.
But I really don't think anybody could have foreseen how bad this really has become.