R Thames flood scheme update
Club News

R Thames flood scheme update

I’m afraid I’ve given you all a bum steer. At the consultation I was told verbally that there would be a control structure between the Thames and Littleton North, and then nothing between that and the fixed crest weir downstream from Big Sheepwalk. David Kennedy provided me with a drawing, dated November 2019 showing an open channel between the Thames and Littleton North and a control structure, with fish pass, between Littleton North and Ellis, upstream of Littleton Lane. I queried this with the EA, and they told me today that this is in fact the case. It will consist of nine radial gates and means that Ellis/Big Sheepwalk will normally only be connected minimally to Littleton North. This is an improvement on what I was told and I think it’s the best we can hope for.

I’ll try and deal with the other points made by members. The original plan did have a bunded channel running through Ellis and Big Sheepwalk but this was speedily dropped – cost I expect.

All the things that Nigel has mentioned, disturbance, water quality etc will no doubt happen, but we have to live in the world as it is. The EA have been test drilling the area for several years so I would think they have a good idea of any pollutants.

Adrian has mentioned the Lea Flood Relief Channel, with which I was fairly familiar when I worked for the EA. It, like the Thames Scheme, but unlike the Jubilee River, runs through several (many?) gravel pits. I can’t offhand remember which ones, but a bit of googling comes up with Nazeing Meads, described as ‘settlement ponds’ for the channel, which appears  to be a successful syndicate water. Adrian could probably come up with more from his Cemex days. My point is that these are, as far as I know, successful fisheries. I do remember one pit controlled by the Lychnobite AS through which the channel ran. The Lychnobites seem to be a very successful club that doesn’t even have a waiting list to join so the fishing can’t be that bad!

I don’t think it would be possible to oppose the whole scheme on the grounds that ‘you’re doing it all wrong’. The Jubilee River, apart from the first time it was used, when it flooded Wraysbury (and collapsed in several places) has been a success in that Maidenhead hasn’t flooded since. The problem with letting the flood water spread across the upper reaches is that all the tributaries downstream from Windsor have a lot of urban runoff and not a lot of uninhabited land to let the flood water spread into. With the increased weir capacities flood water will run off quicker to the tideway.

Regarding increased public access the only part of Ellis/Sheepwalk that the public don’t already have access to is most of Ellis and I can’t really see that being opened up.

Sorry to sound like an EA spokesman!

Regarding the exit weir, not sure of the length, there’s no scale on the drawing but it runs across a widened part of the channel – looks like about about twice the width of the M3. In normal conditions I wouldn’t expect a great amount overtopping – see remarks on sweetening flow above. As this section of the channel bypasses Chertsey weir I would expect the fall to be the same as Chertsey, which isn’t much – only about three feet, it’s one of the shallowest weirs on the Thames.

To sum up, I don’t think the scheme will have a disastrous effect on Ellis/Sheepwalk, there will probably be changes, but, as I said, we have to live in the world as it is.

Ian Campbell

Posted 16/12/22