Quandary
Well-known member
I have been told that from tomorrow the sea locks will be restricted in operation to two hours either side of half tide, not surprising , the reservoirs must be very close to empty.
Crinan Canal restrictions
- Thread starter Quandary
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Quandary
Well-known member
Just to add an update, as well as the constraints based on tide height SC have advised that they wil no longer be operating either of the sea locks on Tuesdays on Wednesdays (even for Bellanoch marina residents).
JumbleDuck
Well-known member
This came today:
Am I right in thinking that the seawater pumping system at Crinan has been out of use for some time?
Am I right in thinking that the seawater pumping system at Crinan has been out of use for some time?
penfold
Well-known member
SC's programme for preventing the use of the canal seems to be progressing well; they've been taking notes from CalMac.
Quandary
Well-known member
The pumps were only used fora couple of years, you can,t mix salty water with fresh in these times, think of the confusion for the poor wee fish.
ctva
Well-known member
Not just that but they bought a freshwater pump and the wrong strainers apparently too.
AND you'd think there was a massive difference in HW / LW so saving lots of water, we're at neaps so for the next week or so the tidal range is averaging LESS THAN a meter. That is miniscule in the amount being saved.
JumbleDuck
Well-known member
You've intrigued me enough to do a wee sum ...
Suppose the area of the locks is AL, the area of the basin is AB and the height through which the sealock level falls is h. That means that the volume of water used in a locking is AL x h, and if all that comes from the basin the consequent fall in basin level is AL x h / AB.
Now, do this again for Lock 14. Lock area AL, drop d, reach area AR, and the drop in the reach level for the locking down into the basin is AL x d / AR.
The drop d in Lock 14 is some base value D plus the drop in the basin, do d = D + AL x h / AB which means that the drop in the reach is
(AL/AR) * x [D + (AL/AB) x h] which means that for a unit change in h, the drop in the reach level is AL^2/(AB x AR).
So all we need to know is the area of a lock (28m x 6m = 168 m^2), the area of Crinan Basin (estimate room for ten puffers, so 1680 m^2) and the western reach (4km x 10m = 40000 m^2) and the ratio above is 0.00042.
In other words, for every drop in sea level at Crinan sea lock of 1m, I reckon a locking out of the canal drops the western reach level by an extra half a millimetre. How perturbing.
Jodel
Active member
I've seen Carp and Mullet swimming side by side in Bilbao. They didn't seem to mind the mix.
ctva
Well-known member
Go on, put that post on the Crinan Canal FB post...
Quandary
Well-known member
Go on, put that post on the Crinan Canal FB post...
That will confuse them!
The restriction is certainly causing some heat in Ardrishaig, a bit from the yachties trying to get through but a massive amount from the locals trying to get home from work.
adwuk
Active member
No need for anything so complex. Close the sea lock, and the leaks will have it filled within the hour, ready for the next customer
JumbleDuck
Well-known member
Fair point.No need for anything so complex. Close the sea lock, and the leaks will have it filled within the hour, ready for the next customer
tyce
Well-known member
I had the misfortune of coming through today west to east. Utter chaos, a brilliant effort by the lock keepers especially Douglas at Crinan sea lock. Round the Mull for me next time me thinks.
JumbleDuck
Well-known member
Do tell.
ctva
Well-known member
And you never said hello. As JD said, do tell.
penfold
Well-known member
Pump into a tank to lower, then drain it back to fill and top up losses from the basin; that or the canal will cease to have any purpose if this carries on. The sealock is always going to be fluctuating from brackish to full briny anyway.
D
Deleted member 36384
Guest
Indeed. As a lover of the canal and a trip through it, always with a positive experience, more preferable to me that the boring MOK, even I have been put off using it when I return to the Clyde this winter. I just can't be bothered with the potential for hassle, so the MOK is the easier option than this shit.
Quandary
Well-known member
I think some of you are being a bit unfair, it has not rained here since March, the soil in my garden is bone dry and dusty 200mm. down. Mid Argyll has never experienced such a long dry spell, most of the recent showers have gone elsewhere. The reservoirs are close to empty. The pumps at Crinan pushed water up in to the long 3 mile west reach, not the locks or the basin, even if they did work environmental attitudes today are very different now. All of the losses are on this western reach (the water waster on the east reach was running full bore last sunday morning as the short water courses which run in to it brought an overnight local thunderstorm output down.) The practice of puddled clay lining has not been used for nearly 20 years and the water just seeps away into the River Add. That is why the sluices at Dunardry are left up overnight. SC have done well on this occasion to keep going for such a long time without water. The suddeness of the closure announcement was what brough chaos, nothing to do with the guys working on the system. Yachties could have done a lot more by co-operating in sharing locks earlier rather than insisting on solo passage, I was surprised the canal was not a lot firmer about that last month.
As for carp and mullet, the canal has proper fish, mainly smallish brown trout with some sea trout which might be able to survive, not sure what they would find to eat though.
As for carp and mullet, the canal has proper fish, mainly smallish brown trout with some sea trout which might be able to survive, not sure what they would find to eat though.
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D
Deleted member 36384
Guest
It’s more that the water shortage Quandary. You have been quite vocal on Scottish Canal’s failings. The Crinan Canal is failing both as a transit facility and as a tourist asset that can be exploited. Neither failings are being reversed by Scottish Canals.
tyce
Well-known member
The issues yesterday were a combination of 3 things.
1 Gale force winds meaning an increase in traffic- hardly the canals fault.
2 The zero notice of the two hour tidal gate at both ends. Hence 20 boats at Crinan basin. They knew the water levels were low so why not make the decision a few days in advance. The lock keepers further through the canal were fuming because they were not even aware of the time restrictions until the boats passing through told them.
3 Staff shortages. The lock keepers did a great job,
they worked through their lunches and worked late to get us through. The Crinan keeper worked his day off when the canal was closed to ensure we all got in, in some nasty weather. However despite all this it was chaotic, no one to open bridges, 1 keeper working both flights of locks etc. The workforce were not a happy bunch.At one time I was one of 3 boats waiting an hour for a bridge swing tied to a pontoon that was out of service, and was secured with poly prop rope 6 mm thick in 30 - 40 mph winds with no other options, that was interesting. Then the East side sea Lock broke. But it was fixed reasonably quickly so good effort.
Of all the boats that went in we were lucky and got through in the 1 day. 1 of 4 boats that managed this. This was done by the keepers working late and a very helpful pilot mucking in didn’t get his name but has a car valeting business. We never planned to do it in 1 day but we were strongly advised to because of the buildup of boats in front and behind us.
In stark contrast the passage West a couple of weeks previous was a relaxed and enjoyable affair.
1 Gale force winds meaning an increase in traffic- hardly the canals fault.
2 The zero notice of the two hour tidal gate at both ends. Hence 20 boats at Crinan basin. They knew the water levels were low so why not make the decision a few days in advance. The lock keepers further through the canal were fuming because they were not even aware of the time restrictions until the boats passing through told them.
3 Staff shortages. The lock keepers did a great job,
they worked through their lunches and worked late to get us through. The Crinan keeper worked his day off when the canal was closed to ensure we all got in, in some nasty weather. However despite all this it was chaotic, no one to open bridges, 1 keeper working both flights of locks etc. The workforce were not a happy bunch.At one time I was one of 3 boats waiting an hour for a bridge swing tied to a pontoon that was out of service, and was secured with poly prop rope 6 mm thick in 30 - 40 mph winds with no other options, that was interesting. Then the East side sea Lock broke. But it was fixed reasonably quickly so good effort.
Of all the boats that went in we were lucky and got through in the 1 day. 1 of 4 boats that managed this. This was done by the keepers working late and a very helpful pilot mucking in didn’t get his name but has a car valeting business. We never planned to do it in 1 day but we were strongly advised to because of the buildup of boats in front and behind us.
In stark contrast the passage West a couple of weeks previous was a relaxed and enjoyable affair.
