> Having good access to flow data for the Thames I looked up daily flows
> at Kingston since the 1880s ( to 2008). I chose a fairly arbitrary
> 'high flow' (200 m3/sec) and looked at the number of days/year when
> this flow was exceeded - assuming that this would be in some sense
> proportional to the probability of a cancelled regatta. Allowing for
> the fact that such a long flow record is subject to many
> uncertainties, and both the river and measuring techniques have
> changed a lot in the last 130 years - the picture is interesting.
> There are 15 years when there are more than 40 days (against an
> average of 25 days) with flow >200 m3/sec - 1883 , 1903, 1910, 1912,
> 1915, 1916, 1919, 1924, 1925, 1926, 1927, 1928, 1936, 1937, 1951,
> 1960, 1995, 2000, 2001 and 2007. 1915, 1961 and 1951 top this
> particular league table. The 1960s, 1970s and 1980s were notable in
> that it was a period without many hydrological extremes, (drought and
> flood in 1976 excepted!) . This pattern of quiescence in the hydrology
> of SE England at this time has been recognised in other datasets.
> The dataset doesn't support a hypothesis that high flows are
> increasing overall, and in fact you would probably have suffered more
> if you had been rowing in the 1920s - pity the rower who started a
> competitive career in 1924!. In fact the 1910-1930 period is the only
> decade in the record when there were never less than 10 high flow days
> a year.
> It does suggest that many current veterans will have learnt to row
> during a period when the number of high flow days was generally low. I
> am sure thatthis is coupled with an increase in risk aversion on the
> part of organisers, and perhaps less opportunity to reschedule events
> in a more complex world!
> Andy McKenzie
That is most informative, for which many thanks! Interesting in what it
tells us and also in what, by its very nature, it leaves out.
Thus years 1894, 1947 & 2003 do not feature in your selection, although
these saw the worst Thames floods on easily accessible record.
Clearly there may be a number of weekends in any year during which flows
are considered high or too high for rowing, but the incidence of such
may bear no relation to whether that year also had exceptional peak
flows. For a brief view of the historical perspective, it is worth reading:
The period 1091 to 1093 might have been bad for rowing events ;)
I can recall a Weybridge Silver Sculls when there was so much stream
that it was somewhat dodgy racing up through the old Walton Bridge,
indeed there was a fair bit of chaos after one sculler got it wrong
under the narrow arch.
I have a feeling that more events do get cancelled now under conditions
where once they'd have been raced - not so long back we didn't have red
& yellow boarding. It is not always clear that the risks are really
that high, & the flow speeds when cancellations of upriver events, &
upriver training in general, occur are often slower than on the Tideway
with a good ebb running - at which times a lot of upriver crews descend
on the Tideway for training.
Carl Douglas Racing Shells -
Fine Small-Boats/AeRoWing Low-drag Riggers/Advanced Accessories
Write: Harris Boatyard, Laleham Reach, Chertsey KT16 8RP, UK
URLs: www.carldouglas.co.uk (boats) & www.aerowing.co.uk (riggers)