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Thames conditions


blackrose

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Flows on the Thames have really increased over the past couple of days, Most reaches are on yellow "Stream Increasing" warnings and a few are on Red Boards.

 

http://riverconditions.environment-agency.gov.uk/

 

It's probably running past me at about 3 knots now. What happens to all this water - will most of it just run out to sea or are they abstracting it to fill up the reservoirs?

Edited by blackrose
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I'm a little bemused as to what else you think it will do? Set up residence in a little bed-sit in Chelsea?

 

Richard

 

I'm a little bemused as to why you feel you need to respond so negatively Richard? Perhaps you never heard that sarcasm is the lowest form of wit.

 

I asked what most of the water will do? i.e. How much of it is abstracted to fill the reservoirs and how efficient is that process?

 

I thought someone with some knowledge of the subject might respond. There's no need to be sarcastic, if you don't know just say so or keep quiet.

Edited by blackrose
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Combined with the wind blowing against the strong current, there were rolling breakers on the Thames at Abingdon! Made for an interesting row in the eight on Thursday evening - I got rather drenched when a particular wave washed over the side of the boat! :blink:

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I'm a little bemused as to why you feel you need to respond so negatively Richard? Perhaps you never heard that sarcasm is the lowest form of wit.

 

I asked what most of the water will do? i.e. How much of it is abstracted to fill the reservoirs and how efficient is that process?

 

I thought someone with some knowledge of the subject might respond. There's no need to be sarcastic, if you don't know just say so or keep quiet.

 

 

Actually this is quite interesting and a reasonable comment.....water is extracted from the Thames just above Staines and fed into the reservoirs.

 

Most of the year this presents no problem but come Autumn an EA worker has to be on site 24 hours a day to clear the filters of leaves at the extraction point.

 

I could not believe it until he purchased (under the RTB scheme) a nice Thameside cottage he occupied by the sluice .

 

Leo.

Edited by LEO
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Unfortunately, even though we live in one of the most temperate climatic countries in the world no-one has seen fit to try and capitalise on our weather. As with most of the rain that falls, it either floods low lying areas where the ground cannot soak it up for one reason or another; it runs into rivers causing mayhem in places like York, Sheffield, Stratford etc etc and then it runs out to sea.

 

I think the problem is that the relevant agencies panic when there's no rain and then it rains and they turn round and say "OK no need to panic now its raining"..............so it gets wasted.

 

Thankfully where I live we were fortunate enough to have a visit from Cornelius Vermuyden so we have a network of dykes and drains which are filling up nicely with the run off from the land. That will certainly help our farmers if not our domestic water supply.

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Flows on the Thames have really increased over the past couple of days, Most reaches are on yellow "Stream Increasing" warnings and a few are on Red Boards.

 

 

Keep a check on those mooring lines over night blackie, looks like more water on its way.

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I believe there is also a massive pipeline that brings water from the upper Thames to London's east end to be processed for tap drinking water.

 

Called the River Thames -----------it generally agreed that the water that comes out of the pipes/taps in London has been filtered and used by nine people before it's used by Londoners.

 

The water for London's east end is contained in the Reservoirs in the Enfield area, fed by the streams from the Stort, Lea and other rivers.

 

L.

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It can work both ways, and is occasionally tested like this. It will be used this way during the Queens pageant.

 

Mike

I was thinking about the pagent. I would have expected it to have been designed for the weight to be on the seaward side. Any idea how much it leaks when it's closed?

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I was thinking about the pagent. I would have expected it to have been designed for the weight to be on the seaward side. Any idea how much it leaks when it's closed?

 

I think the normal plan is to close it at low tide. Somewhere I have an old engineering supplement about it and if I remember right they talked of an upstream rise of about 1' an hour due to fresh flow, ebb remnants and presumably leakage, meanwhile the water downstream rises at something like 1m a hour. I suspect some water can get past the mechanism on each side and possibly some through the base, I have had a look at my barrier photos but they don't give any clues.

 

There is a site which I have always meant to read with loads of info on tidal flows, I will find it and post a link. Link here.

 

We were at Wallingford earlier to check our ropes. Just before the red boards advisory came through two narrowboats came upstream, noticeably slowed through the bridge but were very much in control and moored very neatly despite the water swirling along at I guess around 3mph. We need to head down for Teddington next weekend, first lot of pageant rehearsals the following weekend, it may be a fast journey using very little diesel!

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The EA have a video animation here

 

Looks like no leakage through the sides but the base leaks nicely- photos here. The underspill is particularly impressive when they raise the gate past vertical prior to opening it.

 

There is a great aerial photograph here but I reckon that is with the gates in the underspill position.

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I think the normal plan is to close it at low tide. Somewhere I have an old engineering supplement about it and if I remember right they talked of an upstream rise of about 1' an hour due to fresh flow, ebb remnants and presumably leakage, meanwhile the water downstream rises at something like 1m a hour. I suspect some water can get past the mechanism on each side and possibly some through the base, I have had a look at my barrier photos but they don't give any clues.

 

There is a site which I have always meant to read with loads of info on tidal flows, I will find it and post a link. Link here.

 

We were at Wallingford earlier to check our ropes. Just before the red boards advisory came through two narrowboats came upstream, noticeably slowed through the bridge but were very much in control and moored very neatly despite the water swirling along at I guess around 3mph. We need to head down for Teddington next weekend, first lot of pageant rehearsals the following weekend, it may be a fast journey using very little diesel!

Are they closing the barrier or will you be dodging around in the tide?

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Are they closing the barrier or will you be dodging around in the tide?

 

For the pageant they are closing it, I am hoping that the plan is to close it a little after low water so that people have the tide to help them get into position and the Thames does not look too muddy ... I suspect that rehearsals will be easier in some ways as the tide will be there pushing people along.

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The flow is certainly increasing and the strong wind is creating quite a swell. I'm moored at Walton-on-Thames where the level has increased 4 inches today and I'm think of getting seasickness pills.

 

Flows on the Thames have really increased over the past couple of days, Most reaches are on yellow "Stream Increasing" warnings and a few are on Red Boards.

 

http://riverconditions.environment-agency.gov.uk/

 

It's probably running past me at about 3 knots now. What happens to all this water - will most of it just run out to sea or are they abstracting it to fill up the reservoirs?

 

I see that tonight 12 reaches are now Red with all others Yellow.

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I imagine Thames Water and Veolia will be filling up their bankside storage as much as they can, although the Thames is normally able to supply the treatment works that abstract from it all your round. Having been involved in water treatment in that part of the world since 2001, i can't remember any periods where treatment works had to reduce abstraction because of low river flows (although I could be wrong). Places like Hampton have a design capacity of about 850 Megalitres per day too!

 

There is/was a plan to capture all these high winter flows and store them in a new reservoir at Abingdon, but I'm not sure this will ever get built.

 

There is an awful lot of river flow/ level control that happens on the Thames at the locks and weirs as anyone who's been there around Henley week will know. The EA are probably more keen to get rid of the water as quickly as possible to prevent flooding rather than hold levels up to provide water companies with an extra reserve of raw water.

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I'm a little bemused as to what else you think it will do? Set up residence in a little bed-sit in Chelsea?

 

Richard

Well i think that RWLP's remark was good humour.

 

In the wider reaches of the upper thames water can reach a dizzy speed of 5 miles per hour!

 

as has been already stated, the imperative is to dump excess water to prevent flooding.

 

:cheers:

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I imagine Thames Water and Veolia will be filling up their bankside storage as much as they can, although the Thames is normally able to supply the treatment works that abstract from it all your round. Having been involved in water treatment in that part of the world since 2001, i can't remember any periods where treatment works had to reduce abstraction because of low river flows (although I could be wrong). Places like Hampton have a design capacity of about 850 Megalitres per day too!

 

There is/was a plan to capture all these high winter flows and store them in a new reservoir at Abingdon, but I'm not sure this will ever get built.

 

There is an awful lot of river flow/ level control that happens on the Thames at the locks and weirs as anyone who's been there around Henley week will know. The EA are probably more keen to get rid of the water as quickly as possible to prevent flooding rather than hold levels up to provide water companies with an extra reserve of raw water.

 

 

There was a discussion some year(s) ago over on the YBW forum where it was said that Thames Water shut down their intakes in times of high flow (go figure...), they said the water was too turbid.

 

The Abingdon plan was rejected somewhere along the planning process - so that won't happen. Unless of course a bit more pressure is brought to bear.

 

Time was when water companies had large investment in filter beds(e.g. Kingston) , secondary reservoirs (Barn Elms). These were all declared redundant and are now disused.

It's so much cheaper to abstract water from underground aquifers where the filtration has been done for you - but these take decades to fill.

 

A reality check is needed.

Perhaps the Gov't will have a brainwave and create huge projects to address the problem and provide much needed employment.

 

 

 

In your dreams, Sonny.

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We were on the EA mooring below Penton Hook lock Friday night, both boats needed to empty elsans and fill with water so yesterday we both moved down and are now moored behind Desborough Island. The cruise down was uneventful bur fast, although turning was interesting. Woke up this AM to find that levels have risen about 4 or 5 inches, and they are still rising, 6 more inches and it is over the bank. Our first experience of such conditions on the Thames. We have scrabble and loads of books on board,

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