18 March 2010

Managing flooding in Kingston

The Kingston upon Thames Society continues to serve up a tempting feast of meetings each month.

This month's meeting examined what is being done to reduce the risk of, and impact of, flooding in the area which is a hot topic for various reasons, not just climate change.

The talk was given by Graham Piper Project Manager, Lower Thames Strategy, Environment Agency who, as you would hope from his job title, knows a lot about the subject.

His presentation covered a lot of ground in welcome detail and while the dark implications of a major flooding event hung over the meeting there was certainly some optimism too.

The planning has moved on in recent years from just showing which areas will be flooded to showing the order in which roads will flood.

This simple bit of extra information helps plan evacuation routes etc. and so will help to reduce the impact of the floods when they come.

There are also some major works planned to reduce (not remove) the risk of flooding which essentially come down to allowing the water get to the sea faster by cutting diversion channels and increasing the capacity of the river, particularly as the weirs.

The only black spot in the evening was when we were told that a 1 in 20 year event has a 5% chance of happening each other. While it might seem that 1/20 in the same as 5% it is not. In fact if something has a 5% chance of happening a year then it is more likely than not to happen in 14 years (0.95**14 = 0.49). I did ask if they meant 5% or 1/20 but they did not understand the question so I did not get an answer.

At least the evening ended on a high point when I made contact with some other people there who had also joined the recently formed Friends of Ham Lands. And the ending note got even higher when they mentioned a great web site with lots of photos of Ham and I had to admit that it was mine!

No comments:

Post a comment

All comments are welcome. Comments are moderated only to keep out the spammers and all valid comments are published, even those that I disagree with!