New Crinan Canal Locks (Large File Size Pictures)

[BlowingOldBoots]

Just had a tour of the lock leading into the basin at Crinan. Quite fascinating listening to the changes in lock gate design and some of the environmental activities underway.

The lock gates are all steel and built in the UK. The main difference is that they are fully supported on their hinges at all times, unlike the old gates. The wooden balance beam is for show and not needed on these electric screw driven gates (not hydraulic). The old gates, once closed and their buoyancy lost as the water level dropped, rocked forward and sat on the cill which put a lot of force onto the hinges. Now the gates push against the cill edge and do not rest on the cill at all. The gates have numerous pads at the hinge side and opposite side spread along the faces. When the gates close the pads push against their opposite number either in the hinge or on the other gate. The pads are engineered to not compress by any noticeable amount and last for around 25 years and can be changed in situ. I thought the bolting, using double Nyloc nuts was very suspect considering the multitude of reliable securing devices on the market. Running around the hinge side, bottom edge and on one of the gates contact face, is a large rubber seal which will compress to hold back the water. The gates require great accuracy to set up. There are 13 known leaks along the banks, I forgot to ask if they had plugged them up.

There was a lot of work on the environment side to make sure that the silt and water did not damage the moine as they drained the canal. There was a survey of the amount of water to be dumped and that was passed to external experts who decided that it was not harmful. There are a number of plugs running along the canal and they have been connected to new operating screws to be able to lift at any time. The basin at Crinan and along some of the reaches has an obvious build up of silt and debris but they will not be removing any, except the stuff that is a hazard. The reason is that they don't have the land capacity to store the dredged material or the budget to analyse it and take it away for dumping elsewhere. It does appear to be a lost opportunity. They captured all the fish and the total count was very low as apparently the canal has a dearth of nutrients in it which is not that good for aquatic life. On the banks, they had to review all the fauna and make sure that it was preserved. A lady on the tour who retuned to the area after a long absence said she was surprised at the quantity of flowers and butterflies on the banks. They mow around the orchids for example, so that they are preserved.

All in all, the new gates and works appear to be a reasonable attempt at preserving the the life of the canal. They did say that while the canal is listed as something or another (can't remember) it does not have to be preserved as a museum piece, hence all the gates and bridges can be in any style.

Factoid Time. Loch Ness is officially a Reservoir because the canal maintains the level artificially high. It therefore needs to be managed to ensure that over topping and embankment / dam collapse is not a risk to people living in the area.

[BlowingOldBoots]

Untitled by Rival Sailor, on Flickr

THE GATES WITH PADS VISIBLE

Untitled by Rival Sailor, on Flickr

CLOSED GATES PADS TOUCHING

[BlowingOldBoots]

Untitled by Rival Sailor, on Flickr

COFFER DAM

Untitled by Rival Sailor, on Flickr

OPEN GATES _ BEFORE THE BASIN

[BlowingOldBoots]

Untitled by Rival Sailor, on Flickr

THE PADS ON THE GATE EDGE THAT WILL CONTACT THE OTHER GATE EDGE

Untitled by Rival Sailor, on Flickr

THE PADS THAT CONTACT INSIDE THE HINGE SPACE

[BlowingOldBoots]

Untitled by Rival Sailor, on Flickr

SEAL ON THE DOOR EDGE

Untitled by Rival Sailor, on Flickr

SEAL ON THE HINGE EDGE

Untitled by Rival Sailor, on Flickr

BOTTOM EDGE SEAL AND SPACER

[BlowingOldBoots]

Untitled by Rival Sailor, on Flickr

CILL THAT THE GATE DOES NOT FIT INTO LIKE THE OLD GATES. GATE BUTS AGAINST CILL.

Untitled by Rival Sailor, on Flickr

THE CILL

[BlowingOldBoots]

Untitled by Rival Sailor, on Flickr

A GATE

Untitled by Rival Sailor, on Flickr

A PAIR OF GATES JUST BEFORE THE BASIN

[BlowingOldBoots]

Untitled by Rival Sailor, on Flickr

THE BASIN

Untitled by Rival Sailor, on Flickr

THE BASIN AT THE GATES WHERE OLD REEKIE BERTHED

[BlowingOldBoots]

Untitled by Rival Sailor, on Flickr

OLD GATES

Untitled by Rival Sailor, on Flickr

MORE OLD GATES

Untitled by Rival Sailor, on Flickr

A WRECK

[BlowingOldBoots]

Untitled by Rival Sailor, on Flickr

A PLUG HOLE FOR DRAINING THE CANAL

Untitled by Rival Sailor, on Flickr

PLUG HOLE OPERATING MECHANISM

Untitled by Rival Sailor, on Flickr

THE NARROW BIT WITH THE WOODEN BUFFER

[Aja]

Interesting. Thanks for the photos and update.

Donald

[wully]

Cool. I might trundle along on mah bike for a look.

[Gardenshed]

interesting post
glad we didn't know about the "plugs" along the length of the canal in the early '80s, that'd have been quite a temptation during the Tobermory race or the weekend of West Highland week.....
disappointing that they didn't take the opportunity to remove the silt and rubbish whilst the canal was drained. Definitely a missed opportunity. Surely the old lock gates and more obvious larger items will be moved?

[Corona]

The new lock gates have proved to be less than an improvement, requiring much more time and effort than before. Perhaps canal builders in the past knew more about what they were doing?
The Cairnbaan flight with four old locks can be passed in around one hour, the Dunardry flight with three old and two new sets of gates now takes an experienced operator three to four hours. Some of this can be explained by the absence of Russ who managed that flight for the last few summers but most is down to the new gates. Reusing the old pumps with new sluices has been a mistake and some of the sluices with their sophisticated? seals can not be moved when the lock is full. The awkward position of the pumps also makes it harder. The physical effort required to move the new gates at 12 and 13 is usually beyond the effort of one person and SC have acknowledged this with notices on the swing bars. MacKenzies workers talked a better story but the job they have left is even worse than the contractors from the previous winter.
However the major issue arises from the decision to replace from the bottom up, the new lower gates below the old leaky one further up the flight means that the pressure from the flow of water overtopping the new gates means that the gates can not be opened until the water level in the reach above has dropped adding up to an hour to the locking time for each set. Scottish Canals decision not to bother with grouting the lock walls when they were empty is another puzzling decision.
Age may be a factor but the extended time and effort required this year demands a day of recovery now after nearly every transit.

[Peter Pilot]

Corona,

All your observations are spot on.