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Canal Closed


Mick and Maggie

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The locks between Bradford on Avon and Hanham are in a perilous state. Many leaks through the chamber walls (similar problem in waiting to the above one? We had lock 11 closed to repair a crumbling wall only two weeks ago..), gates that don't sit properly and don't butt together but 'overlap' , worn and leaking paddle gear, and generaly the structures are only just hanging together.

The problem is made worse because these locks are heavily used, and get a lot of impact damage. Gate qoins get badly damaged by boats slamming into the gates, and only opening one gate to enter/exit makes things worse. There are some very tight turns out of and into the shortly spaced locks, and the walls are bearing the scars of boats coming out to fast, and being unable to make the turn.

 

 

Hi.

 

We are on the K&A at the moment. presently in Devizes and intending to descend the Caen hill flight in the morning. Well we were untill we heard that lock 17 was closed untill further notice!

 

Thus far, I must say that this canal has not reached expectations. What Luc is saying makes us think if it is worth going on, should the lock reopen !

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It would seem that Lock 20 is not a circa 250 year old structure. From Narrowboat World (it is perhaps worth noting that Lock 20 is the 'youngest' of the locks in the flight, built later to help control the water levels and variations in pound depths.)

 

Mick

 

Oh goodness, you're right! That one is only 200 years old

 

That was mentioned earlier in one of the threads

 

Do you think we can sue the builder?

 

Richard

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When I first came down the Buckby flight on Old Friends 5 years ago , I noticed that the side wall had a spectacular fountain on the houses side that was in an exact aim of my engine 'ole hatch, and it watered my brasses good and proper on the way down. By the time the lock gates opened, this had generally almost stopped. Since then, I have always kept the engine hatch shut when descending this lock.

I came down this week late evening with another boat, the back pumps were on and the pounds were more than full. There was also at least one boat coming down behind us.

The last two locks took almost half an hour each to descend due to the top gates overflow, and I had to run down the bottom lock to open all the paddles to stop the houses flooding whilst descending lock 12.

The towpath was underwater in several places and people came out to see what the noise was from the Niagara over the bottom gates..

The last lock took ages, and the spectacular fountain above continued, even after the lock was left, and gates closed.

Whatever cavity is behind the lock wall there is now several times larger than it was 5 years ago, and more, a local lock keeper or lengthsman would have identified that by now, volunteer lockies are just there to........

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Ok, what's this all about?

 

Things happen to the structure of the canal all the time, you seem to be very passionate about this particular occurrence. I can see a pretty normal incident on a 200 year old system - what is it about this particular one that is getting under your skin?

 

Richard

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Ok, what's this all about?

 

Things happen to the structure of the canal all the time, you seem to be very passionate about this particular occurrence. I can see a pretty normal incident on a 200 year old system - what is it about this particular one that is getting under your skin?

 

Richard

I have tracked down the Builder

451px-James_Brindley_by_Francis_Parsons.

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When I first came down the Buckby flight on Old Friends 5 years ago , I noticed that the side wall had a spectacular fountain on the houses side that was in an exact aim of my engine 'ole hatch, and it watered my brasses good and proper on the way down. By the time the lock gates opened, this had generally almost stopped. Since then, I have always kept the engine hatch shut when descending this lock.

I came down this week late evening with another boat, the back pumps were on and the pounds were more than full. There was also at least one boat coming down behind us.

The last two locks took almost half an hour each to descend due to the top gates overflow, and I had to run down the bottom lock to open all the paddles to stop the houses flooding whilst descending lock 12.

The towpath was underwater in several places and people came out to see what the noise was from the Niagara over the bottom gates..

The last lock took ages, and the spectacular fountain above continued, even after the lock was left, and gates closed.

Whatever cavity is behind the lock wall there is now several times larger than it was 5 years ago, and more, a local lock keeper or lengthsman would have identified that by now, volunteer lockies are just there to........

 

There are many many locks that have these dreaded water jets, some quite severe. I do not believe that they just happen, they are in fact created by CaRT because they ALL line up with either the engine room hatch or an open port-hole, another plot by CaRT to pss off boaters.

 

But seriously, CaRT are aware of these. On the K&A every lock is inspected every two weeks (or is it 4 weeks?) and this includes a full fill and empty. I assume all of the waterways are also checked. I believe there have been experiments to inject something in to seal these leaks. The only real solution is to rebuild the walls but this would be rather expensive.

 

............Dave

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I have tracked down the Builder

He was just playing at it, a cowboy builder who took year and years to complete a small job. In ancient China, large canals for river transport had already been established. The longest being the Grand Canal of China. Which is still the longest canal in the world today, and the oldest extant one. Which is not bad considering that it is over 1100 miles long. The project began in 605 and was completed in 609. Even in its narrowest sections it is rarely less than 90 feet wide. Imagine building a canal 1100 miles long and a minimum of 98 feet wide in just four years. Then some 1400 years later is is still in daily use. All on a bowl of rice a day.

 

regards

 

Mick

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A void has appeared in a lock wall closing the Wolverhampton 21.

 

Another instance of a lock fail causing a canal to close.

 

Good old CaRT

 

 

The fact that 16 pounds of water were loosed off down the flight in the middle of the night which flooded houses and caused considerable damage may have had an adverse effect on lock 20!

Stop knocking CRT when you dont know the facts.

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But seriously, CaRT are aware of these. On the K&A every lock is inspected every two weeks (or is it 4 weeks?) and this includes a full fill and empty. I assume all of the waterways are also checked. I believe there have been experiments to inject something in to seal these leaks. The only real solution is to rebuild the walls but this would be rather expensive.

I noticed when wandering about rcently that quite a few locks appear to have had the original stones concreted over. Probably a short term solution as the water pressure is constant so I would imagine leaks will start again fairly soon.

CART's awareness, as was BW's, is of course welcome. Action is sometimes nice, too...

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Lawrence's post raises the issue of flooded houses and that is pretty awfull. It isn't CaRTs fault or BW ,it is the fault of the vandals who loosed off the water.

I'm very sorry for the flooded house holders, the vandals want rounding up and setting to work learning to do something constructive.

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It does look as though a long bar has been inserted into the crack and the wall levered away from the side, crumbling the bricks in the process.

 

 

 

Have you ever tried to demolish a wall?

 

The hole towards the centre will be from the investigation.

 

Richard

 

 

I suspect that the flood water poured over the lock side and has taken the wall with it, 16 locks worth of water is a huge flow rate and will move mountains, once the smallest of cracks appears and the turbulence of the water can get behind it as well as the flow over the effective weir crest, then it stood no chance, you can see bad scouring at the centre where the failure will have happened. Compare the wall in my bad pictures to the wall after the flood and you can see how far it has pushed the wall over.

 

I was at CRT Milton Keynes today, and we had an informal chat with Vince Moran, the director responsible for operations.

 

There is no suggestion of direct vandalising of the individual lock structure, (e.g. by levering), but they do consider that there is a very good chance that the opening of paddles all the way up the flight could have helped bring about the collapse. This was apparently a massive release of water, (so they say!).

 

As people probably know, all structures like locks get inspected by CRT on a regular basis, and graded on perceived condition. This lock had a "middle" ranking condition, (I think he said "C" on a scale of "A" to "E", but may be remembering wrong), so was not thought to be any higher risk than many others on the system, and would not until this point have featured high op any list of "which one do we expect to collapse next".

 

Obviously with hindsight this lock was in worse condition than inspections had led them to believe, but it apparently showed no greater structural defects than are normal in one of its age.

 

However it seems bizarre to me that anyone likens this to something like doing MOT inspections on cars! Bald tyres, rusty brake pipes, etc are rather easier to spot than trying to second guess what may be happening behind 200 year old lock walls, maybe several feet thick.

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I was at CRT Milton Keynes today, and we had an informal chat with Vince Moran, the director responsible for operations.

 

There is no suggestion of direct vandalising of the individual lock structure, (e.g. by levering), but they do consider that there is a very good chance that the opening of paddles all the way up the flight could have helped bring about the collapse. This was apparently a massive release of water, (so they say!).

 

As people probably know, all structures like locks get inspected by CRT on a regular basis, and graded on perceived condition. This lock had a "middle" ranking condition, (I think he said "C" on a scale of "A" to "E", but may be remembering wrong), so was not thought to be any higher risk than many others on the system, and would not until this point have featured high op any list of "which one do we expect to collapse next".

 

Obviously with hindsight this lock was in worse condition than inspections had led them to believe, but it apparently showed no greater structural defects than are normal in one of its age.

 

However it seems bizarre to me that anyone likens this to something like doing MOT inspections on cars! Bald tyres, rusty brake pipes, etc are rather easier to spot than trying to second guess what may be happening behind 200 year old lock walls, maybe several feet thick.

I suspect water spouting out of walls when a lock is being emptied is easy to spot and should give an 'MOT fail' just as corroded brake pipes do. It is an indicator that a failure might occur.

 

.... and I think that someone has stated that this happens at this lock.

 

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I suspect water spouting out of walls when a lock is being emptied is easy to spot and should give an 'MOT fail' just as corroded brake pipes do. It is an indicator that a failure might occur.

 

.... and I think that someone has stated that this happens at this lock.

 

Water probably spouts out the walls of at least 10%, and almost certainly 20% of all locks on the system when they are emptied.

 

Are we suggesting every such lock should receive a total rebuild in case it is in danger of imminent failure?

 

How would that be funded?

 

 

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Water probably spouts out the walls of at least 10%, and almost certainly 20% of all locks on the system when they are emptied.

 

Are we suggesting every such lock should receive a total rebuild in case it is in danger of imminent failure?

 

How would that be funded?

 

No but I would suggest that though that these are the locks that are closely monitored for movement and changes in the volume/number of spouts.

 

We need to be realistic I would rather boat using ageing infrastructure which sometimes failed than get a reinforced concrete screed on lock walls and lock gates replaced with modern steel hydraulic gates. We can knock successive governments and years of BW for lack of maintenance. Maintenance is cheaper than repairs but Im not going to blame CRT every time something fails.

 

All the proposed changes to VM's , RMP,s , winter moorings , guidance on CC'ing are irrelevant if we can't get maintenance right and therefore move around the system so if there is a list of priorities.......

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Water probably spouts out the walls of at least 10%, and almost certainly 20% of all locks on the system when they are emptied.

 

Are we suggesting every such lock should receive a total rebuild in case it is in danger of imminent failure?

 

How would that be funded?

 

 

Indeed they do. Many locks have at least a dribble here and there. I would suspect this started to happen just a few years after they were originally built. In the end it is a process that eats away at the mortar the walls but takes a long time. I doubt there would be sufficient funds even if you doubled CRTs grant/income to fix all locks that had a leak in the lock wall.

 

I was told some years ago by a BW engineer that there are several different reasons for leaking walls that spout water when emptied some more serious than others. Most he said were just porous mortar and bricks and some small voids and takes many years to become serious. However if there get joined up and more substantial amounts of water can build up in larger voids this can more seriously weaken the structure. one of the worst kind is where the canal is trying in effect to circumvent the lock by a channel and void being formed that is gradually connecting the top of the lock running down behind the lock wall and into the bottom pound. This seriously weakens the structure and woudl need digging back and walls being reinforced or rebuilt.

 

What type of problem a leaking lock has is not obvious from the leak itself more in what's behind it. Although he did say the faster the leak into the empty lock goes from a spout to a dribble or stops the less serious it is.

Edited by churchward
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Water probably spouts out the walls of at least 10%, and almost certainly 20% of all locks on the system when they are emptied.

 

Are we suggesting every such lock should receive a total rebuild in case it is in danger of imminent failure?

 

How would that be funded?

 

 

I have a cunning plan! What we will do is to categorise these locks as being in condition 'C' rather than 'D'.

 

That way we can simply wait for them to fail before fixing them.

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All major assets like locks and bridges are monitored, and an attempt made to classify them in order not only of condition, but also rate of deterioration.

I have been to presentations by CRT where they make it clear that what gets priority is not determined solely by what is in worst condition, though.

 

If something is being monitored, is in poor state, but judged to not be dangerous or in danger of imminent failure, it can lose out on the priority stakes, either to something in less poor state, but where safety is at issue, or something in less poor state, but where the implications of not attending to it promptly may massively increase the final bill. In other words, sometimes a concious decision is made not to give something priority, because although it is known not to be "100%" it is judged it will remain OK for a while, and the ultimate remedial work will not be significantly higher if repairs are deferred, but the situation monitored.

Vince Moran pulls no punches that they are constantly having to juggle to make best use of available resources, and that it is inevitable sometimes that they will get it wrong.

Loads of Internet pundits and NBW contributors seem to know after the event that there was a problem brewing at a location where a failure has occurred, but I'm sure people also know of worrying signs at high numbers of locations where no failure has occurred, and none ever will.

Does anybody think they can accurately predict (say) the next three major failures? No, of course none of us can if we are honest, and that is the dilemma for CRT - some of the issues at these structures can probably only be found by pulling them apart.

 

As I have said in response to the Aylesbury Arm failure, it has now been discovered that the failed lock is far less substantially built than others on the arm, but nobody knows why. It had not stopped it standing for 200 years, but that bit of information may well be a contributory fact in its failure. I'm not enough of an engineer to know if you can start a program that non destructively tests every lock to see if it actually contains less brick or stonework than people have hitherto assumed it did, but I kind of assume such a program might be far from trivial?

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No but I would suggest that though that these are the locks that are closely monitored for movement and changes in the volume/number of spouts.

We need to be realistic I would rather boat using ageing infrastructure which sometimes failed than get a reinforced concrete screed on lock walls and lock gates replaced with modern steel hydraulic gates. We can knock successive governments and years of BW for lack of maintenance. Maintenance is cheaper than repairs but Im not going to blame CRT every time something fails.

 

Quite so, but I doubt that a concrete screed covered walls would fix the issue anyway. When these structures collapse it is because of pressure from behind the wall as for instance the collapse on the Aylesbury arm. It has been shown that covering a mortared brick structure in concrete can accelerate failure particularly if lime mortar was used between the bricks. The policy of covering canal bridges in concrete render failed to stabilise the bricks in many cases and caused many structural problems for example. Many bridges so treated have had it removed when chunks of it started to come off anyway.

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Your quite right I was hopefully being tongue in cheek re screed and gates. You are right regarding the render - it didn't work . I assume you could perhaps pin the wall back , but guess the answer has to be stopping the water ingress in the first place. With the wet summers and cold winters we could be into more problems unfortunately.

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Loads of Internet pundits and NBW contributors seem to know after the event that there was a problem brewing at a location where a failure has occurred, but I'm sure people also know of worrying signs at high numbers of locations where no failure has occurred, and none ever will. Does anybody think they can accurately predict (say) the next three major failures? No, of course none of us can if we are honest, and that is the dilemma for CRT - some of the issues at these structures can probably only be found by pulling them apart.

 

Alan, I agree, these are the very questions being asked after the event by various 'pundits'... They are also likely to be the very same questions being asked after an event with a more significant outcome. Questions asked by the HSE and Coroners Courts. No amount of money saving excuses or hand wringing or apologies will count then. I seem to think that the lock count is now at least three with similar sorts of problems this cruising season, care to speculate on what it will be by the end of the current season?

 

I remember last year being held up on our cruise for several weeks when a cill blew out on a Leeds Liverpool lock. At that time there was a BW boat in the lock when the lock blew. A deliberate policy of under spending on essential maintenance over a number of years is a questionable action. It would be hard to defend such and action in a court. With recent changes around culpability it is only a matter of time, not if - but when!

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I suspect there is a lesson here in reinforcing the use of the vandal locks. Sections of this flight have been drained repeatedly since late last year; the first draining got into the paper as I remember.

 

Edit for link. http://www.expressandstar.com/news/2012/11/28/canal-water-drained-in-attack-by-wolverhampton-vandals/

 

I often walk down on my way to work and it's not unusual to see the locks off in the early morning. Some scrote has taken advantage of that and I fear it's likely to happen again. They've likely picked up a windlass lost along the way.

Edited by Smelly
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Does anyone on here realize exactly how much water was released on this occasion? We are talking of lock 16 to 19 which is about a mile and a half of canal, that amounted to a tidal wave breaching the banks, the damage IS considerable and all down to vandalism. Dean Davies (CRT manager West Mids) reassures me that every effort is in place to reopen the flight as soon as possible, he is not happy that the BCN main line is closed off in peak summer.


I suspect there is a lesson here in reinforcing the use of the vandal locks. Sections of this flight have been drained repeatedly since late last year; the first draining got into the paper as I remember.

Edit for link. http://www.expressandstar.com/news/2012/11/28/canal-water-drained-in-attack-by-wolverhampton-vandals/

I often walk down on my way to work and it's not unusual to see the locks off in the early morning. Some scrote has taken advantage of that and I fear it's likely to happen again. They've likely picked up a windlass lost along the way.

 

Anti vandal locks are in place but vandals soon find a way round them as do we when we forget our key, have you tried opening one with a biro case? it works!

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..................care to speculate on what it will be by the end of the current season?

 

No, not at all!

 

I'm not denying that for many years not enough has been spent on maintenance.

 

Many, many, many years - half a century at least, it is hardly a new thing.

 

The problem as I see it, is that it is little point complaining about everything that has not happened in the past - all that is really worth talking about is the "now", and how we move forward from a situation that reflects where we are now.

 

Now I can certainly make some suggestions about not wasting money on less important matters, (the South East Visitor Mooring exercise would be high up my list!), but however upset you get about mismanagement of some areas, correcting those will certainly not provide a fraction of the shortfall that would be required to do the most detailed possible survey of every potentially dodgy structure on the system, and, if required, to put each in good order.

 

What is plain is that Vince Moran simply does not have the budget, (and will likely never have a fraction of the required budget), to inspect every lock or bridge that may have any cracking or other defects in it, and to do detailed investigations of (just as examples!) every lock where water drains through holes in the side as it is emptied.

 

So, if you feel those things have to be done on a very much larger scale than now, (and I'm sure most of us would fully agree that would be the ideal situation), can you explain where you think the funding will come from, please?

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