Friday, August 22, 2014

In Today's Flash Flooding News

Our cousins in Winnipeg are dealing with the celestial overflow that triggered flash flooding.  The Weather Network attributed it to the, by now standard, slow-moving rainstorm that hit the city and lingered long enough to deliver more than 75 mm. or 3" of rain in about 90-minutes.


It's been a common story this summer.   Heavy rainstorms that used to move steadily eastward, spreading rainfall across wide areas, now loiter.  When these storms park over one area they deliver amounts of rainfall that quickly overwhelm first storm sewers and then other infrastructure such as roads.

In the States, flash flooding has hit Chicago and parts of Arizona.


Beijing York said...

It really was something else. The basement in our building had some 4-5 inches of water but luckily it drained some.

We were once caught in a flash flood in Spain were there were serious casualties - collapsed buildings and roads in the aftermath. The rail lines were closed down (we were scheduled to leave by train) and we managed to get the last bus out before they closed that down.

Luckily it wasn't as intense in Winnipeg last night but it certainly was unexpected and it seems the unexpected is increasingly becoming the norm.

The Mound of Sound said...

There's an added dimension to this, BY. Most prize fighters can take a punch but what separates the champions is how they can take a series of punches.

How often can a particular community endure flash flooding? How many floods can it sustain before it becomes unlivable? That very issue is now being discussed in England where historic villages along once pastoral water courses are being inundated annually. In some, the costs of repeated restoration are becoming prohibitive and local authorities are warning they may have to be abandoned.

You can amortize "once a century" storms over the course of a century. When they arrive every few years it's a different matter.