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Steve · November 10th 06, 12:25 PM posted to uk.transport.london

On 9 Nov 2006 11:04:38 -0800, wrote:
but in between I
suppose it must be due to higher flows down the Thames.

The differance between summer and winter is quite significant, but the
quote was "now bursts its banks almost daily between March and September"
eg not in winter, maybe the quote just has the period the wrong way round.

Checking the tide tables for london bridge shows no real difference between
the months, excluding the equinox periods. Having a better search found
this[1]

"The closure of the Thames Barrier can be a response not only to tidal
surges but also to heavy rainfall. In the unusual winter of 2000/01 there
were, as was stated above, 24 Barrier closures, as opposed to the usual
three or so, largely in response to the extremely heavy rainfall on the
Thames and its tributaries. We were told that ¡§The volume of tidal water
kept out of London by the Thames Barrier ¡V when closed ¡V is some ten to
twenty times the amount of river water flowing the other way, even after
very heavy rainfall. As a result, closing the gates at low water and
holding out the tide can create a useful ¡¥reservoir¡¦ behind the gates ¡V
into which the rain-swollen river can flow. If the Barrier remains open in
such circumstances, the river would effectively be ¡¥pushed back¡¦ by the
incoming tide. This makes it much more likely that floodwater would be
forced to spill out over the riverbanks in vulnerable areas of West London
such as Hammersmith, Chiswick and Richmond¡¨. It is expected that
low-lying areas and towpaths will be under floodwaters more frequently. "

So it seems that quote must be backwards

Steve

[1]From http://www.london.gov.uk/assembly/re...t/flooding.rtf