Cill damage at lock 59 Kennet & Avon Canal

[Steve Manc]

Recently whilst waiting to go through locks and watching other narrowboats how they operate them.

 

We like to be at the back of the lock which at times can make it more difficult for us.

 

I note others like to ride the cill then have the front of the boat travel up against the lock gates.

 

Q, does riding the cill contribute to a damaged cill

 

Q, perhaps this is the only way a single manner can manage the lock.

 

Q, were the locks designed to have a narrowboat ride the cill

 

These are questions and not accusing anyone of damage 

 

https://canalrivertrust.org.uk/notices/0197d498-7071-74b7-b7f3-11523e399d3f

Edited July 4 by Steve Manc
Grammar

[Arthur Marshall]

Certainly not the only way a single hander can go up locks. I've never ridden the gate and never would. If there's nobody on the boat it looks like a recipe for disaster, there are so many ways to get the bow stuck on a bit of knackered lock.

I can see why a 70 foot boat would do it. I've always thought anyone would have to be out of their mind to try it on a short boat like my 40 footer. Infinitely safer to tie the thing up in the middle of the lock and then bring it up carefully.

All that being said, plenty of singlehanders seem to do it and haven't sunk. Yet.

 

[ditchcrawler]

3 hours ago, Arthur Marshall said:

Certainly not the only way a single hander can go up locks. I've never ridden the gate and never would. If there's nobody on the boat it looks like a recipe for disaster, there are so many ways to get the bow stuck on a bit of knackered lock.

I can see why a 70 foot boat would do it. I've always thought anyone would have to be out of their mind to try it on a short boat like my 40 footer. Infinitely safer to tie the thing up in the middle of the lock and then bring it up carefully.

All that being said, plenty of singlehanders seem to do it and haven't sunk. Yet.

 

Hopefully they don't wander off for a pint while the lock is filling so if anything does catch they can drop the paddles and then there is no disaster. I am not sure what someone on the boat could do.

[magpie patrick]

4 hours ago, Steve Manc said:

Recently whilst waiting to go through locks and watching other narrowboats how they operate them.

 

We like to be at the back of the lock which at times can make it more difficult for us.

 

I note others like to ride the cill then have the front of the boat travel up against the lock gates.

 

Q, does riding the cill contribute to a damaged cill

 

Q, perhaps this is the only way a single manner can manage the lock.

 

Q, were the locks designed to have a narrowboat ride the cill

 

These are questions and not accusing anyone of damage 

 

https://canalrivertrust.org.uk/notices/0197d498-7071-74b7-b7f3-11523e399d3f

 

I suspect it's the cill for the bottom gates that is causing the problem - they seem to go more often, possibly because the damage is unseen until they fail.

 

At the top six locks at Crofton any boat riding the top will be riding the gates not the cill as they are not that deep. 

 

Single handing Lutine through these I went up the ladder towards the back of the lock and used the centre rope to hold her roughly mid way in the chamber (45 foot boat) so the back deck was by the ladder and the front some ten feet from the gates, doing the same with Juno, 23 foot, I foolishly went up the ladder nearer the top gate and sure enough got the pulpit rail stuck under a beam on the gate. 

[David Mack]

5 hours ago, Steve Manc said:

 

Q, does riding the cill contribute to a damaged cill

Yes it could damage the part of the cill facing into the lock chamber. But many locks have (or in some cases had) a loose timber beam held on by chains provided specifically as a bump board to absorb the energy from an entering boat. These were designed to be replaced from time to time, but I'm not sure CRT bother these days.

But a boat bumping or riding the cill in this way does not affect the timber beam against which the top gate(s) seals - that is further upstream and the sealing face faces the other way.

[Arthur Marshall]

3 hours ago, ditchcrawler said:

Hopefully they don't wander off for a pint while the lock is filling so if anything does catch they can drop the paddles and then there is no disaster. I am not sure what someone on the boat could do.

Someone on the boat could move it back from the lock gate. It's why engines have reverse. It just seems daft to me to take the risk, but as I said, plenty do. I prefer to avoid a potential panic paddle drop, if you'll pardon the alliteration. I'm sure, with an experienced boater, it's perfectly safe 95% of the time.

[Mike Todd]

Depends on specific lock design.  Some intentionally create a strong forward pull on the boat, so long as it us close enough to the top. The closeness depends on the lock! In some cases, the pull us too strong for the boat in full reverse to resist and the result is a substantial impact in cill or gate. It us quite easy to muss tge pull staring until it us too late to do anything about it.

 

My understanding us that this was intentional for full length boats, not many short boats anyway.

 

In some locks there is a specific bumper board that hangs in front of the cill.  I am not sure whether it is to limit the effect of unintentional impacts or whether it was accepted practice.

 

Although the practice is called riding the cill, I suspect that it is a misnomer in the sense that  the cill is the angled shape that the gates fit against, below water, to create a seal, along with the way in which the champhered edges come together vertically. In most cases, the riding is against the main bulk of the lock below the cill. This arrangement can be seen clearly in deeper locks where the lower water level is below the cill.

 

I also suspect that damage is largely done on an impact rather than sustained pressure on what is a large wall. So, if tte steere comes into the lock and reaches the far end at 'zero' speed then not much happens.

 

In many narrow locks the gate itself is protected with a thick steel plate, again seemingly intended to mitigate the effect of a boat's bow on it. It also ensures that the bist does not catch under the balance beam.

 

There are various reasons why the practice is helpful to traditional boaters which are different to today's boating scenario. 

 

How many boats will enter a full lock from above and fail to come to a full halt before reaching the bottom gates. Impact here is more likely to have a serious consequence.

 

Hanging too far back risks either the rudder or something else  being trapped between the gates, leading to a sinking.

 

Overall, there many ways of working a lock, whether single handed or not. I do not believe that any if them are without some downside so it is up to the steerer to make their own risk assessment.

[Wanderer Vagabond]

9 minutes ago, Arthur Marshall said:

Someone on the boat could move it back from the lock gate. It's why engines have reverse. It just seems daft to me to take the risk, but as I said, plenty do. I prefer to avoid a potential panic paddle drop, if you'll pardon the alliteration. I'm sure, with an experienced boater, it's perfectly safe 95% of the time.

From an experience at Ryders Green a few years back I have learned never to rely on an engine in the lock. I had chugged in at a perfectly reasonable speed and put the engine into reverse to come to a halt without hitting the bottom gate, sadly the plastic bags that then wrapped themselves around the prop had other ideas and now I'm drifting towards the bottom gate with no means of stopping. I grabbed the centre rope and stepped off in an effort to stop, but by then it was too late and I hit the gate harder than I would ever wish to do (fortunately without causing any obvious damage). Since then I go into a lock at much the same speed as I did then, but step off with the centre line and put a single loop around one of the lock bollards and gently bring the boat to a halt with that. Never failed me since (except on the occasion I put the loop the wrong way around and it locked off, stopping the boat almost immediately)

[David Mack]

17 minutes ago, Arthur Marshall said:

Someone on the boat could move it back from the lock gate. It's why engines have reverse. It just seems daft to me to take the risk, but as I said, plenty do.

That's fine if the boat is half the length of the lock, but impractical with a full length boat - as soon as the engine has got the boat moving backwards you then have to go into forward gear again to stop the stern hitting the bottom gate. Keeping clear of both ends using the engine is almost impossible, especially when you also have to consider the changing draw as the lock fills or empties. You would have far more success using ropes around a bollard.

[ditchcrawler]

23 minutes ago, Wanderer Vagabond said:

  (except on the occasion I put the loop the wrong way around and it locked off, stopping the boat almost immediately)

You would, or maybe wouldn't be surprised by the number of boat owners who don't know that 

[Wanderer Vagabond]

44 minutes ago, ditchcrawler said:

You would, or maybe wouldn't be surprised by the number of boat owners who don't know that 

Once you've got it wrong to tend to remember for the future

[Arthur Marshall]

2 hours ago, David Mack said:

That's fine if the boat is half the length of the lock, but impractical with a full length boat - as soon as the engine has got the boat moving backwards you then have to go into forward gear again to stop the stern hitting the bottom gate. Keeping clear of both ends using the engine is almost impossible, especially when you also have to consider the changing draw as the lock fills or empties. You would have far more success using ropes around a bollard.

Indeed, which is why, I imagine, the whole riding the gate thing started - because it's logical for a full length boat. But most boats these days aren't, I suspect most are about 55 foot and a fair few, like mine, are much shorter, when, I think, it makes little sense and carries a greater risk than tying the boat up. Other opinions are available and equally valid (except, of course, that I'm right and everyone else is wrong...).

Like everything else with boats, it's up to the individual who knows the boat and what they're comfortable with. What's dangerous is to imagine there's a universal best way, or, even worse, a "right" way to do stuff.

[David Mack]

45 minutes ago, Arthur Marshall said:

But most boats these days aren't, I suspect most are about 55 foot

I think there's a fair few boaters of 55ft boats who by use of engine alone would struggle to keep the boat's movements within the 20ft or so available to them.

[MtB]

9 hours ago, David Mack said:

I think there's a fair few boaters of 55ft boats who by use of engine alone would struggle to keep the boat's movements within the 20ft or so available to them.

 

That certainly includes me as a single hander on the bank, controlling my boat in the lock!

[Allan(nb Albert)]

17 hours ago, David Mack said:

Yes it could damage the part of the cill facing into the lock chamber. But many locks have (or in some cases had) a loose timber beam held on by chains provided specifically as a bump board to absorb the energy from an entering boat. These were designed to be replaced from time to time, but I'm not sure CRT bother these days.

But a boat bumping or riding the cill in this way does not affect the timber beam against which the top gate(s) seals - that is further upstream and the sealing face faces the other way.

Some years ago, at a lock open day on the Hatton flight, I commented on the poor state of one of the remaining bump boards and asked if it would be replaced. I was told that it would be removed as these boards were no longer needed. The reason given was that boats are now under 70 foot ...

[Wafi]

9 minutes ago, Allan(nb Albert) said:

Some years ago, at a lock open day on the Hatton flight, I commented on the poor state of one of the remaining bump boards and asked if it would be replaced. I was told that it would be removed as these boards were no longer needed. The reason given was that boats are now under 70 foot ...

Maybe the dry weather has been causing them all to shrink.

 

Seriously though, I think this is the sort of thing the Historic Narrowboat Club would like to be informed about; one of their stated aims is "To promote and campaign for the retention and/or reinstatement of appropriate traditional and historical waterway furniture, features and working practices". Not suggesting you report a comment from several years ago, but worth people knowing that there is a group that campaigns to maintain historical features.

[Steve Manc]

23 hours ago, ditchcrawler said:

You would, or maybe wouldn't be surprised by the number of boat owners who don't know that 

I cannot say we use this practice!

 

What is the right way ?

[beerbeerbeerbeerbeer]

On 04/07/2025 at 18:32, Wanderer Vagabond said:

(except on the occasion I put the loop the wrong way around and it locked off, stopping the boat almost immediately)

and also there’s definitely a chance of the rope pulling itself off the bollard if you get it very wrong,

 

 

[brianthesnail96]

3 hours ago, Steve Manc said:

I cannot say we use this practice!

 

What is the right way ?

 

I'm glad you asked. I've been trying to get my head around it!

[Wanderer Vagabond]

15 hours ago, Steve Manc said:

I cannot say we use this practice!

 

What is the right way ?

Basically you don't want the rope to cross, so if the lock is full and therefore the rope going to the centre line cleat goes upwards, the rope should come to it from the top of the loop, if the lock is empty and the rope going to the centre line cleat goes downwards, the rope should go to it from the bottom of the loop. You want the line to go around the bollard without crossing over ('cos that's what leads it to 'lock off')

11 hours ago, beerbeerbeerbeerbeer said:

and also there’s definitely a chance of the rope pulling itself off the bollard if you get it very wrong,

 

 

Whenever that has happened I've just put another loop over it. I'm always standing quite close to the bollard when doing this. It's more likely to happen as the centre line cleat is almost in line with the bollard, once it has passed it rarely happens.

[Mike Todd]

20 hours ago, Steve Manc said:

I cannot say we use this practice!

 

What is the right way ?

Traditionally, a stern strap was passed around the gate (esp when descending a narrow lock) which closed the lock and stopped the boat in one move. Of course, such a practice is now deprecated as too many people get it wrong and cause more damage than anything else.

 

There are videos about that show some of the ways in which 'traditional' boaters saved time and/or effort - such as opening bottom gates in a wide lock when descending. These are fascinating and important to understand if seeking to discover the reasons for certain aspects of lock design. Bit it does mean that answering the question about what is the right way is complicated because, for an experienced steerer, the best and/or traditional technique is no longer available. For example, in some places where a narrow top gate once had a reinforced upstand to the outer vertical edge, that is now obstructed so that a rope cannot be passed around, or newer locks omit the feature.

 

AFAIK, the original designers of locks and canals did not issue a manual about the correct way to use them. Hence, even traditional means what users gradually worked out for themselves - with owner and operator having conflicting objectives!

[David Mack]

18 hours ago, Mike Todd said:

Hence, even traditional means what users gradually worked out for themselves - with owner and operator having conflicting objectives!

Not really. In the days of commercial carrying it was in the interest of both the canal company and individual boatmen to make the passage of locks as fast as possible, and so it was in the company's interest to add facilities to achieve this. Such features could range from strapping posts and upper gate paddles to speed lock operation, through to gas lighting to allow 24 hour operation (Farmers Bridge flight) to duplicate locks (Hillmorton, Cheshire Locks, parts of Ashton Canal etc.) and even complete bypass routes (Tame Valley Canal).

[Mike Todd]

I had thought that there were plenty of reports of Canal Companies objecting to some of the ways in which boaters used the locks (and other assets) because they caused damage and cost the company money as well as loss of tolls if there was a closure. OTOH, I cannot lay hand to a specific reference - I am sure someone will.

 

Stand alone strapping posts are a bit different - used in place of brakes! - in that damage to them does not cause a stoppage and their replacement is relatively cheap.

[beerbeerbeerbeerbeer]

3 minutes ago, Mike Todd said:

I had thought that there were plenty of reports of Canal Companies objecting to some of the ways in which boaters used the locks (and other assets) because they caused damage and cost the company money as well as loss of tolls if there was a closure. OTOH, I cannot lay hand to a specific reference - I am sure someone will.

I can’t remember where I read it but the slamming of top gates shut wasn’t tolerated,

that is opening the bottom paddles early and thus drawing the top gate shut quicker was not allowed/permitted because of potential damage,

 

 

[Mike Todd]

4 minutes ago, beerbeerbeerbeerbeer said:

I can’t remember where I read it but the slamming of top gates shut wasn’t tolerated,

that is opening the bottom paddles early and thus drawing the top gate shut quicker was not allowed/permitted because of potential damage,

 

 

Lots of things were not permitted but that does not say that they did not happen. Otherwise, why so many "DO NOT  . . " notices, some of which persist in odd places. I suspect that such practices were only forbidden after it was found that they were happening. A list of all possible or plausible malpractices would be very long indeed.