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magpie patrick

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Everything posted by magpie patrick

  1. Are you sure? They're on the same bit of coast twelve miles apart!
  2. Lets put it to CRT that the Grand Union should be modified in this way - narrow entrances to wide locks - problem solved
  3. French Canal Lock with Balance Beams And standard mechanised type - not exactly leak free Both on the Canal du Nivernais
  4. Which waterway is that? Like many in France, it seems to capture a certain air of genteel neglect! Most french locks are mechanised, but before this they were windlass operated gates: by the late 20th century very few had balance beams (and those that did still generally have them). They also had strict rules and lock keepers to enforce them, amongst those being that gates had to be fully opened before the boat approched them, not least because the gates are much more fragile than ours anyway. The evolution and operation of French locks and their funishings is a fascintaing subject that would merit more research - from what I've seen so far there were many differences with out own. some locks were much more rudimentary, and they never went for locks that took two narrow boats side by side - it's that last factor which is said toi be causing the problem on our lock gates
  5. It happens on narrow locks - is that due to canoes using only one gate?
  6. This post cannot be displayed because it is in a forum which requires at least 10 posts to view.
  7. TBH I don't think there are ANY locations where this is beneficial for the reason stated, as in to make sure both gates are open There is no particular location where lock gates are getting disproportionately scraoed or clobbered as a result of only opening one gate. The leak due to scraping is easy to fix, the leak due to clobbering less so. If a gate is ONLY leaking through the scrape on the mitre it's doing okay, leaks under and round gates are a bigger problem generally. If CRT are of a mind to encourage bpaters to open both gates they should do exactly that - years ago BW changed policy to closing gates behind you and it now gets nearly 100% compliance - widely promote a policy of opening both gates and in 5 to 10 years there will be widespread compliance. Paradoxically mechanised locks might be most beneficial in long flights such as Wigan and Caen Hill, but the potential for disruption when they fail is also greatest here, any one lock in the flight failing would cause problems.
  8. Footbridges on the tail of every lock would be an alternative - the most common reason for not opening one gate on a wide lock is, I suspect, the walk round to do it. Certainly that's why I'm resistant to it when on my own.
  9. Whilst it's not quite the same thing, the deepest lock (and certainly the deepest narrow lock) in Martin Clark's list that hasn't got deeper since it was built is Lock 15 at Marple, 13 foot 4 inches - I accept some deeper locks may have been deeper than this before subsidence, but I suspect not http://www.penninewaterways.co.uk/locks.htm
  10. Now there's a good idea! Boats to carry a long pole and the offside gate to have a hook to engage it. I guess the gates would need to be balanced well for this to work but it's a lot simpler and easier than electrification! (Yes, I'm serious)
  11. Thanks for the on-the-spot info Jen - the breakdowns are a serious issue that needs to be addressed - this happens with other equipment too - we got held up at Wooton Rivers when the pumps feeding the K&A summit failed. Thorne Lock allows one gate only opening as this gets a longer narrow boat into the lock - blimmin sight cheaper than lengthening the lock! I have twice recommended mechanising locks, neither has happened. Both were on restoration schemes and in both instances the lock house was a private residence prior to restoration - mechanisation would have allowed the locks to be operated from the side opposite the house. In the end negotiations with the house occupants, along with some mitigation such as fencing and access gates, made this unnecessary. If there is a good one-off candidate for mechanisation it might be Bradford Lock on the K&A, but this is the first lock for a lot of hirers and they "cut their teeth" on it - I'm not keen on hirers then going down the locks in Bath without this practice run. Bradford lock takes a hammering from the number (and dare I say competence) of users, but the hydrailics would also take a hammering, I could see them failing a lot. When we went on the Yorkshire Waterways as kids, the mechanised locks just had big hydraulic rams fastened to the balance beams*, and out of hours the connecting pins were taken out so the lock could be worked manually. If popular locks are to be mechanised they need a manual override. *These rams could open the gates against a foot of water, and often did, which shortened the life of the gate! It also masked the leakage problems to the extent that some locks were virtually impossible to operate manually.
  12. This old chestnut... Electrification is not cheap, needs a power source and is another thing to go wrong. In some limited instances it is a good idea but if you think the cost of gate replacement is high then the cost of maintaining several hundred electrically operated locks would be eye watering - it's not just the power supply but the inspection, maintanance of moving parts and replacement etc Second, a gate operated by a hydraulic ram is subject to different loads - you CAN just fasten a ram to an existing gate but over time it damages the gate. The ram can also apply a lot more force to the gate than a boaters backside on a balance beam can, so the gates need to be more substantial to deal with this. Third, the boats brushing on gates is easily fixed with sacrificial wooden strips on the mitre post - this damage happens on narrow locks too and also potentially where pairs of narrow boats enter a lock side by side. Gates get brushed against unless the lock is quite a lot bigger than the boats entering - it would help if gates went all the way into the gate recesses - too often they don't The REAL cause of damage to the closed gate is not brushing it but hitting it, especially when going downstream when the gate can't just move out of the way on impact. The most brutal damage to gates is caused by hitting them when they have a head of water against them.
  13. There is a very fundamental conceptual difference in that the lock is designed to enable boats to change level and the pound between locks is not!
  14. Would fossile fuels melt it? Keep it at a 2 inch draft and just use a small electric outboard?
  15. On the greening of the BCN, it has happened everywhere old industry has gone, certainly mining - it is hard to believe now that Radstock was the biggest mining town in this area along with Midsomer Norton, Welton and Paulton, only the odd conical batch (coal tip) gives it away - the older, irregular batches just look like wooded hillsides. It won't be that long and there will only be the miners memorial in Radstock to remind us That happens to be on the line of the short lived branch of the Coal Canal so it's a good excuse to post a picture
  16. I think (but stand to be corrected) that there is a difference between damage caused by the stolen vehicle and recovery of the vehicle - technically the insurance company (a) need to recover the vehicle to asses the claim and ( b) assuming it's a total loss they then own it and would be required to remove it anyway - on the latter if it still belongs to the insured then their losses in recovery are covered by the insurance. I have once had a car stolen and it was recovered by my breakdown company having been found abandoned with their sticker in the window - they billed my insurance company for the recovery (the car was repairable so it wasn't a total loss)
  17. Agreed, and the factor most likely to reduce the fall is the upper pound being down rather than the lower pound being up - it is not uncommon at Marple to see pounds 18 inches down and still passable - 18 inches UP would be over the towpath. If the upper pound is down the apparent fall when looking at the lock won't be altered. It is for this reason that, to my eyes, Etruria top looks deeper than anything esle, it has rather more spare wall when full. As an aside, having grown up with Marple locks, it still takes me slightly by surprise elsewhere when I can step off the lockside onto the cabin roof with the lock empty!
  18. Picking up on this one again - the other distinguishing feature of narrow canals isn't just the width of the boats (approx 7 feet) but their length - 70-72 feet, broad canals and rivers have varying lock lengths from around 55 foot to well over 80 foot, but narrow boats are (or were) very much "about 70 foot long. The south Wales canal boats were short - the Mon and Brec were 64 foot long, the Glamorgan and Neath were 60 foot (and boat approx 9 foot wide) - the Swansea was the closest to narrow boat standard and 69 foot by 7 foot 6 inches. Incidentally, if the Glamorgan were defined as narrow it would undoubtedly have had the deepest narrow lock - the two rise at Aberfan had a fall of 29 feet so about 14 foot 6 for eaxh chamber. Only apart of the wall survives now. Picture of them below taken from the linked website http://www.alangeorge.co.uk/glamorganshirecanal_page2.htm
  19. They don't really count as narrow, being designed for vessels over 8 feet wide! Bath Deep Lock is just under 19 feet deep - it is user operated and thus is the deepest user operated lock on the system - it is, however, wide! Bath Deep Lock combines the fall of the former Bridge Lock (9) and Chapel Lock (8) and is more or less on the site of Bridge Lock - nothing remains of either of the old locks and one can't easily tell where Chapel Lock was other than the obvious - it was next to the Chapel you refer to.
  20. Those are good points well made and reinforce the view I often express that there is no such thing as a standard narrow boat, and thus also no such thing as a standard narrow lock, there are subtle but important variations in length and beam and it is unreasonable to expect, for example, that a GU Town Class narrow boat can go everywhere on "narrow canals" - the designers of such boats never dreamt anyone would try and take them up the Chesterfield Canal for example - it doesn't mean they won't fit, it means the designer never intended them for such far flung waterways
  21. IanD's picture is of the lock at Ardnacrusha on the Shannon - it's a two-rise staircase with the top chamber having a fall of around 70 feet and the lower on 30-40 feet depending on the tide level below the lock.
  22. From the shape I guess that's the Caldon basin above the lock rather than the Uttoxeter one below it - quite a contract to today's tranquil scene
  23. Thanks for the answers - as well as the obvious parts of the cruising network there are odd bits of canals such as the Swansea, Grantham and Manchester Bolton and Bury Canal and I was looking at how those might be required to be maintained - roughly, the answer seems to be that they are not. I am told that part of Lapal Tunnel is still in CRT ownership and therefore is a remainder waterway - as the section includes neither portal it is the only waterway in CRT ownership entirely underground!
  24. I get that, but where does the duty to maintain consistent with public safety and amenity come from? Is it a default setting that doesn't need to be specified? Is it supposition that's never been tested? Or is it a sub-section somewhere that I'm not finding?
  25. Just looking for a steer if anyone actually knows... The 1968 Transport Act categorised waterways as commercial, Cruiseway or Remainder (section 104), it is often said (and I;ve always understood) that "the remainder" under that section are to be maintained to the minimum level possible consistent with public safety and amenity. The duties for Commercial and Cruiseway waterways are defined in section 105 of the act, but I can't find anything to say the level of maintainance required (or not required) for "the remainder" Anyone got any pointers?
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