Passage under canal

[magpie patrick]

5 hours ago, Alan de Enfield said:

 

I have always been under the impression a culvert is a waterway underneath a road / railway / canal etc.

Not a footpath,

 

Bit of a grey area - as has been alluded to it's rather like the brodge/tunnel question

We now have box culverts in construction, which are often in effect a bridge but the structure is a box rather than two abutments with a deck spanning the gap - the bridge carrying the Holyhead Road (the old A5) over the Montgomery Canal at Queens Head is a box culvert. 

Going back to the original query I can't think of many pedestrian-only routes under canals, Bugsworth (next to Whaley Bridge Tesco) and Cosgrove are the only two that readily spring to mind, I see that others have already added at least two more to any list. 

3 hours ago, mark99 said:

IIRC the Cosgrove one is cross sectioned like a horse..... for obvious reasons.

 

Are you just wanting "cattle creeps" and or designed for persons?

 

If it's culverts carrying water there are loads.

 

I think a list of people-pipes under canals would be very instructive

Culverts carrying water I should think are beyond counting, there must be many, many hundreds, and even CRT don't always know they are there until they fail

[Scholar Gypsy]

And is there a distinction between an aqueduct and a siphon?

[matty40s]

6 minutes ago, Scholar Gypsy said:

And is there a distinction between an aqueduct and a siphon?

Yes, an aqueduct carries water on a level plane over a dip, even if that dip is because the water is on an embankment. A siphon will carry water higher than its originating level and then down below its originating level.

 

Heres one, theres also a YouTube video somewhere.

https://www.28dayslater.co.uk/threads/the-chew-reservoir-syphon-greenfield-saddleworth-sept-2015.99464/

Edited May 3 by matty40s

[nebulae]

I am fairly sure that the arches under the Monty @ Garthmyl are lime kilns, Will check next time I pass, Logical as this was the end of the canal for 25 years.

[Dorlan]

22 minutes ago, nebulae said:

I am fairly sure that the arches under the Monty @ Garthmyl are lime kilns, Will check next time I pass, Logical as this was the end of the canal for 25 years.

The 1902 25" O.S. map shows limekilns next to the canal at Garthmwl. They were to the left of the cottage in the link to Google Maps that Graham Davis posted.

[Big Bob W]

6 hours ago, matty40s said:

Ah, so not where MikeP narrowed, but at the other end of the field from the lower car park.

I discovered this one last autumn. We were moored just north of Welton Haven near the narrows (Bridge 4?). From the towpath, the brickwork looks like a culvert, but if you climb down the embankment, its quite a well preserved tunnel. Its probably only about 5ft high. I wonder what its purpose was? Cattle creep?

 

[Tim Lewis]

1 hour ago, matty40s said:

Yes, an aqueduct carries water on a level plane over a dip, even if that dip is because the water is on an embankment. A siphon will carry water higher than its originating level and then down below its originating level.

 

Heres one, theres also a YouTube video somewhere.

https://www.28dayslater.co.uk/threads/the-chew-reservoir-syphon-greenfield-saddleworth-sept-2015.99464/

 

Boated down the River Lee last weekend and passing through Ware Lock, which is owned by the EA, the sign on the lockside says 'Ware Lock Weir And Siphon'.  This intrigued me and I cannot find any reference to the siphon bit it on line  ?

[mark99]

There are also storm type tunnels and culverts in the civil world that remain dry for years sometimes. There is a very big parallel bank of them under the M3 around Chersey where (you can walk through them) the M3 is elevated on a large embankment. These must be 20 foot diameter.

Edited May 4 by mark99

[mark99]

Greenwich foot tunnel under Thames.

[David Mack]

10 hours ago, Scholar Gypsy said:

And is there a distinction between an aqueduct and a siphon?

 

Strictly speaking, where a water course is carried below an obstacle, and the top of the underpass is below water level that is an 'inverted syphon', although often referred to as just a 'syphon'.

 

8 hours ago, Tim Lewis said:

 

Boated down the River Lee last weekend and passing through Ware Lock, which is owned by the EA, the sign on the lockside says 'Ware Lock Weir And Siphon'.  This intrigued me and I cannot find any reference to the siphon bit it on line  ?

 

Syphons (the conventional sort, not inverted) were fitted to some weirs on the Lee as part of flood prevention works in the 1970s. They consist of a concrete roof over part of the weir crest, with solid walls either side, and the roof extending to just above normal water level on the upstream side and well down the slope on the downstream side. When the river is in flood the upstream entrance becomes submerged, and the flowing water gradually draws the air out to start the syphon operating (in much the same way as sucking air out of a tube to start a syphon). The advantage of the syphon is that it will shift much more water than a simple weir crest of the same length, so can be used where space is limited. When the flow decreases and the upstream level drops, air is admitted through the inlet and the syphon action stops. In low flow conditions it just operates as a normal weir.

 

1 minute ago, mark99 said:

Greenwich foot tunnel under Thames.

And its twin at Woolwich.

 

It's also not well known that there is a subway through the cills of the Thames Barrier, providing a route for pipes and cables and pedestrian access to all the piers.  I went on a site visit shortly before it was completed and we walked through from the south bank to one of the main piers, but we were told it goes all the way through to the north bank.

Edited May 4 by David Mack

[mark99]

1 minute ago, mark99 said:

Greenwich foot tunnel under Thames. And Woolwich foot tunnel.

 

[Tim Lewis]

6 minutes ago, mark99 said:

Greenwich foot tunnel under Thames.

 

There is a foot Tunnel under the Thames Barrier!

[Scholar Gypsy]

3 minutes ago, David Mack said:

 

Strictly speaking, where a water course is carried below an obstacle, and the top of the underpass is below water level that is an 'inverted syphon', although often referred to as just a 'syphon'.

 

 

 Yes I should have said that.  Here's one (near Brandon in Suffolk) where the cutoff channel (visible here) goes under the Little Ouse (inside the concrete trough at right angles). I think it is possible for this to operate where the "lower" water level is above the "higher" level, if you see what I mean. 

[mark99]

51 minutes ago, David Mack said:

 

It's also not well known that there is a subway through the cills of the Thames Barrier, providing a route for pipes and cables and pedestrian access to all the piers.  I went on a site visit shortly before it was completed and we walked through from the south bank to one of the main piers, but we were told it goes all the way through to the north bank.

 

I guess classified as a "service tunnel"?

 

 

[mark99]

Has this been mentioned?

 

https://www.alamy.com/tunnels-under-the-canal-and-railway-lines-in-bugbrooke-northamptonshire-image360140685.html

[Graham Davis]

14 hours ago, nebulae said:

I am fairly sure that the arches under the Monty @ Garthmyl are lime kilns, Will check next time I pass, Logical as this was the end of the canal for 25 years.

 

13 hours ago, Dorlan said:

The 1902 25" O.S. map shows limekilns next to the canal at Garthmwl. They were to the left of the cottage in the link to Google Maps that Graham Davis posted.

 

Thanks, I did wonder if they were something like that.

[MIKE P]

On 03/05/2021 at 15:34, Dorlan said:

There is a shot of the one at Welton Haven on Google maps...

Welton Haven culvert

Thanks for the photo.

That is the one I was referring to.

[MIKE P]

On 03/05/2021 at 16:40, matty40s said:

Ah, so not where MikeP narrowed, but at the other end of the field from the lower car park.

Yes my mistake, its been a long time since I was there. Although I wasn't too far away.

[1st ade]

Three passages for the price of one (under the Caledonian Canal)

 

[doratheexplorer]

On 04/05/2021 at 08:43, mark99 said:

Greenwich foot tunnel under Thames.

The Woolwich one is better, because it's longer, and you can return by ferry.

Edited May 6 by doratheexplorer

[Scholar Gypsy]

On 06/05/2021 at 14:37, doratheexplorer said:

The Woolwich one is better, because it's longer, and you can return by ferry.

In the vicinity one can cross the river by six methods:

• Tube
• Cable car
• Foot tunnel
• Docklands light railway
• Car ferry
• Thames Clipper

Here are a few photos:  https://scholargypsy.org.uk/2020/02/29/trip-to-london-vts/

Edited May 7 by Scholar Gypsy

[redwing]

 Eddisbury Way under the Shroppie near Tattenhall ?

[doratheexplorer]

On 07/05/2021 at 18:24, Scholar Gypsy said:

In the vicinity one can cross the river by six methods:

• Tube
• Cable car
• Foot tunnel
• Docklands light railway
• Car ferry
• Thames Clipper

Here are a few photos:  https://scholargypsy.org.uk/2020/02/29/trip-to-london-vts/

Swim.

 

[Scholar Gypsy]

42 minutes ago, doratheexplorer said:

Swim.

 

Yes, and that would probably allow you to add "RNLI lifeboat" to the list as well....

[doratheexplorer]

33 minutes ago, Scholar Gypsy said:

Yes, and that would probably allow you to add "RNLI lifeboat" to the list as well....

I've never swum it, but I have crossed by all six of your methods, and also in a Brixham Trawler.