Thursday 1 October 2015
The Thames Barrier Information Centre
This was not an easy place for me to get to, and the bizarre recommendations of TfL's inadequate Journey Planner did not help. Why would I go via Caledonian Road, Kings' Cross and London Bridge, to North Greenwich and a bus, when Camden Road to Stratford, and Stratford to North Greenwich got me to the same bus (the 472, by the way) in 40 minutes instead of 90 minutes? But I digress.
After all the gardens and royals of last week, and being on my own, I decided the time had come for some heavy metal, and you don't get much heavier than the Barrier
The car parks were empty, and the signage on some of the components long gone, but the Barrier itself was spectacular, and I walked for a little way along the Thames Path, admiring the views of the Barrier and also of the surrounding area. The Tate and Lyle factory is just here, resisting the assaults of the anti-sugar faction, and there was an attractive map to show you all the delights of the area. Linda and I had of course been round here on various buses, as well as going to Woolwich to visit Firepower.
There is also a profile of the River along one of the walls here, showing the fall from Thames Head to the estuary: the river begins 105 metres above sea level.
Having got a real impression of just how big the whole thing is, I headed inside to the small Information Centre, which is under the cafe. The lady who took my (very modest) entrance fee mentioned that there was a school party in the place, but we ex-teachers don't mind other people's students, and these were perfectly civilised.
Around the walls is information about the whole length of the river, and an elegiac film of wild life, rippling water, fish and leisure activities. The Environmental Agency is very keen for us to know that the river is actually very clean, though murky from the sediment stirred up by the currents, though I should not care to drink it myself. There is also information about tides and North Sea surges, as well as what happens to the rain which falls in Oxford and Reading. Then there is some history, about previous floods, notable the 1953 disaster. And Bazalgette and his embankments, which of course constrained the river upstream. A summary of climate change science and resulting water levels and flood risks fills another wall
We also learned about Charles Draper, the engineer whose clever idea the system was, though I could not discover whether this piece of paper really was his sketch of the idea, or an artist's version.
But the centrepiece of the exhibition is a working model. Two sheets of foil covered card rise as the tide comes in and the river is swollen with upstream rain; the hydraulic pistons pull and push the wheels into their upright position and lo, London is saved. No-one said much about what happens to Thamesmead and Gravesend as a result, however.
The last ingredient in this very informative Information Centre is a film where one of the top men, in his hard hat and high visibility jacket shows us round the operations room and then down the tunnels which connect the 9 piers, and up onto one of them to see the gates at close quarters. He is accompanied by a cartoon character who provided diagrammatic explanations of the difficult bits. The stainless steel, though eye-stretchingly expensive at the time of construction, wears well, and continues to be beautiful. What I did not know is that the inside of each of these compartments is lined with wood, in a positively cathedral-like vault. We were told that each of the wheels weighs 3,300 tons, and that the cranes are needed to lift them for maintenance. There are emergency generators and back up systems of all kinds. I suppose the strangest thing is that they run water pipes to all 9 piers in case of fire, although you might think there would be enough water all round. My only criticism is that when some science is mentioned, cathodic protection for example, the 'Scientist' is of course depicted as a male with a beard in a white coat. It really is about time for the Environment Agency to review its stereotyping department.
All in all, this is a London sight well worth a visit. My only regret is that I didn't time my trip to coincide with one of the monthly test closures. You can find the dates for these on the website, which also has diagrams and many details.