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Post by Telemachus on Jul 30, 2022 10:58:40 GMT
Prolonged low rainfall means the reservoirs get very low and eventually run out of water. In 1976 the usage of the canals (locks) was massively less than it is today and people were less stupid, so less likely to leave paddles open at both ends etc. That's so, . . but the old/good/correct practice of maintaining canal pound water levels just 'on weir' is not directly related to or the same thing as conserving water supplies by restricting, supervising, or preventing the use of locks, . . and taking steps to minimise leakage. Until such time as no more water can be drawn off canal reservoirs it's essential that pounds are kept up to normal retention levels -- ie. almost full enough to be 'running weir', but not quite. The benefits of this are twofold. Firstly, canal banks and the puddle lining are prevented from drying out and cracking, leading to increased leakage and loss of water, and secondly, . . the fact that the rate of evaporation loss from canal pounds is less than the rate of evaporation loss from reservoirs. Canal pounds are generally shaded from sunlight, and to some extent wind, along some of their length, . . whereas reservoirs don't have anything like the same proportion of the water surface shaded, or anything much in the way of shelter from wind -- which evaporates off water more quickly than sunlight alone. Keeping water in reservoirs, if and when it's still available from them, instead of using it to keep pounds full is the height of stupidity and incompetence. It isn't that C&RT haven't got enough water to keep canal pounds full, . . it's that they're keeping it in the wrong place -- in the reservoirs instead of in the canals themselves. Taking Atherstone as an example, the 8-9 pound although short, is always low. That is because there is a leak somewhere! But there isn't much noticable leakage from lock 9 so it seems certain that the water is leaking away somewhere from the actual canal, maybe a culvert or something. Being just a few 10s of yards long, you wouldn't think it too difficult to track the leak down, but of course that hasn't happened despite it being like that for many years. Perhaps eventually there will be a breach and the CRT will have to do something, but in the mean time, closing the flight means there is less need to keep that pound up which means less water has to be run down. It is the same on many other "problem" pounds I can think of. No obvious leakage around lock gates but nevertheless a chronicly low pound above. As you say that can be detrimental to the puddle, but CRT aren't that clever! I suppose they will be worrying about the fish though!
I suppose the other consideration is that much more of the canal is now piled, so a low water level is less of an issue for the puddle, unless it is really low and the canal bed is exposed.
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Post by Deleted on Jul 30, 2022 11:07:31 GMT
Notice Alert Oxford Canal Location: Hillmorton Lock 2 & 3 - 6 & 7, Oxford Canal Starts At: Lock 2, Hillmorton Bottom Lock (Tp) Ends At: Lock 7, Hillmorton Top Lock (Os) Up Stream Winding Hole: Bridge 74 OX-027-005 Down Stream Winding Hole: Bridge 53 OX-020-017
Friday 12 August 2022 16:00 until further notice
Type: Navigation Closure Reason: Water resources
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Post by Deleted on Jul 30, 2022 11:08:26 GMT
The above update to the timed openings arrived yesterday ianali and Telemachus Closed from 12 August UFN Rog
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Post by Deleted on Jul 30, 2022 11:10:39 GMT
Notice Alert Coventry Canal Location: Atherstone Lock 1 & 5, Coventry Canal Starts At: Lock 1, Atherstone Top Lock Ends At: Lock 5
Friday 12 August 2022 15:30 until further notice
Type: Navigation Closure Reason: Water resources
Same closure for Atherstone.
The closures were an addition to the time restrictions.
Rog
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Post by Tony Dunkley on Jul 30, 2022 11:13:21 GMT
Interesting point that, but isn't most drinking water also stored in large reservoirs. One would think drinking water was more important than canal water. Yes, but rather amazingly if there is a prolonged period without rainfall the reservoirs start to run low as do the rivers from which water is sometimes extracted. No matter how much one has an irrational hatred of CRT, the water outside my boat window is destined to end up eventually in the sea. It's called "gravity" Tony. Funny you should mention that, . . presumably you're thinking about the proposals BWB made to install pumps on the East coast for back pumping into the Hilmorton Pound from the North Sea. Unfortunately it never went ahead -- cancelled due to the massive cost, . . and the sheer stupidity of the idea that any water lost from the North Oxford would ever get anywhere near any part of the UK coastline Any news about the brain transplant yet, . . or the castor implants for your knuckles ?
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Post by Deleted on Jul 30, 2022 11:21:01 GMT
The pound below Banbury on the south Oxford has been similarly losing water for years.
At one point the builders of the new housing were being blamed for extracting water.
I'm certain that water is being lost overnight, but nothing is done to investigate, let alone remedy the problem.
In 2019 we were stuck at Rumps Lock, Middlewich for the weekend because of a dry pound above. They had to run water down from the Macclesfield Canal over the weekend to get us moving.
Once again nothing was done to establish where the water was (and no doubt still is) being lost ... and of course due to neglect of Toddbrooke and its consequences problems currently are seriously exacerbated.
When the system's barely coping anyway, it's not surprising that a period of drought will bite.
Rog
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Post by Deleted on Jul 30, 2022 11:27:26 GMT
Notice Alert Coventry Canal Location: Atherstone Lock 1 & 5, Coventry Canal Starts At: Lock 1, Atherstone Top Lock Ends At: Lock 5 Friday 12 August 2022 15:30 until further notice Type: Navigation Closure Reason: Water resources Same closure for Atherstone. The closures were an addition to the time restrictions. Rog Reading those 2 stoppage emails I got yesterday it does appear that it is a total stoppage as the time restriction stuff is under the heading 'Original Message' so Rog might be correct. If they are shutting those two flights down I would imagine the hire boat companies will not be happy.
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Post by Deleted on Jul 30, 2022 11:35:41 GMT
Also the timed openings are in place now.
The closure is 12 August UFN
Rog
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Post by Tony Dunkley on Jul 30, 2022 11:36:17 GMT
When the system's barely coping anyway, it's not surprising that a period of drought will bite. Rog It isn't the "system", or lack of rainfall, . . it's the useless prats impersonating a navigation authority that aren't coping. Do you have any idea just how much water's left in Naseby, Sulby, and Daventry reservoirs ?
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Post by ianali on Jul 30, 2022 11:36:44 GMT
Notice Alert Coventry Canal Location: Atherstone Lock 1 & 5, Coventry Canal Starts At: Lock 1, Atherstone Top Lock Ends At: Lock 5 Friday 12 August 2022 15:30 until further notice Type: Navigation Closure Reason: Water resources Same closure for Atherstone. The closures were an addition to the time restrictions. Rog Iβve just rang CRT. Lewis told me that his computer says restricted opening. I told him that you had received a message saying complete closure. He says thatβs wrong but will check with the regional office and call me back today. So who knows? Oh, he did say they are closed to widebeams at the moment!
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Post by Deleted on Jul 30, 2022 11:39:25 GMT
Atherstone is closed to wide beams ... what a disgrace of a navigation authority ... I wonder who can champion our complaints π π
Rog
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Post by Telemachus on Jul 30, 2022 11:41:05 GMT
Looking at the CRT stoppages page, the only current one is about the restrictions, there is nothing about closure. Maybe the email was sent out in error? canalrivertrust.org.uk/notices/22942-atherstone-lock-1-and-5-coventry-canalI think the problem arose because someone selected βclosedβ for navigation in the header, when it should have been βopenβ. It is a navigation restriction, not a closure.
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Post by Deleted on Jul 30, 2022 11:42:19 GMT
Also the timed openings are in place now. The closure is 12 August UFN Rog It does strike me as strange that CRT have picked on August 12th. If there is a problem then surely it would be best to restrict movement now rather than wait until things get so serious they have to completely shut the flights. Something strange going on, are we getting taken over by aliens on the 12th?
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Post by naughtyfox on Jul 30, 2022 11:43:10 GMT
That's so, . . but the old/good/correct practice of maintaining canal pound water levels just 'on weir' is not directly related to or the same thing as conserving water supplies by restricting, supervising, or preventing the use of locks, . . and taking steps to minimise leakage. Until such time as no more water can be drawn off canal reservoirs it's essential that pounds are kept up to normal retention levels -- ie. almost full enough to be 'running weir', but not quite. The benefits of this are twofold. Firstly, canal banks and the puddle lining are prevented from drying out and cracking, leading to increased leakage and loss of water, and secondly, . . the fact that the rate of evaporation loss from canal pounds is less than the rate of evaporation loss from reservoirs. Canal pounds are generally shaded from sunlight, and to some extent wind, along some of their length, . . whereas reservoirs don't have anything like the same proportion of the water surface shaded, or anything much in the way of shelter from wind -- which evaporates off water more quickly than sunlight alone. Keeping water in reservoirs, if and when it's still available from them, instead of using it to keep pounds full is the height of stupidity and incompetence. It isn't that C&RT haven't got enough water to keep canal pounds full, . . it's that they're keeping it in the wrong place -- in the reservoirs instead of in the canals themselves. but CRT aren't that clever! There's a good way to see how clever the management of CRT is, and that's by examining their bank statements, and looking at how wealthy that are - what kind of houses they live in, what kind of cars do they drive, and so on. That's what it comes down to at the end of the day. And once retired and out of the game, the running of the waterways is someone else's problem!
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Post by Deleted on Jul 30, 2022 11:43:23 GMT
That is possible ... two errors, one for Atherstone and one for Hillmorton ... but surely more probable that it's been sent out as an advance notice of closure from 12 August ... I cannot see how it reads any other way (both published above) Rog
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