>From an article in my Dutch newspaper I understand that the American Army Corps of Engineers builds levees with an average chance of breakthrough once in 230 years. In the Netherlands the norm is once in 1250 years for the river areas and once in 10,000 years for the cities. According to a Dutch professor the Americans have a different idea about risks.

And have the Dutch dykes actually lasted 1250 - 10,000 years? The proof of the pudding is in the eating. The German 3rd Reich was supposed to last 1,000 years, The Thames Barrier is expected to be swamped within this century, such that they're expecting to build another one further towards the estuary, to protect London and the Essex salt marshes (where, btw, they're expecting to build 1,000s of new homes - maybe on stilts). Older people say about consumer goods "They don't make 'em like they used to", but who's still got a 1950s washing machine, or bacolite TV.

Hmmm, I'm waffling now :-)