Does anyone have any information on the Vyrnwy Aqueduct and how it crosses the Mersey? Apparently it was re-routed under the ship canal in 1978.

Bit of info on it HERE

Some of it crosses at Runcorn irc

Thanks. I know that Vyrnwy is piped directly, but I'm not sure if that's still the case with Alwen Reservoir as it now forms part of the Dee system (similar to Brenig, Bala, Celyn etc). Llyn Celyn was one that interested me quite a bit because of the politics involved in building it. Liverpool City Council apologised for it a few years ago.

not that it will help much,but i was at lake vyrnwy a few months back and was told whilst there that this lake was dammed for the purpose of delivering water to liverpool,which i thought was amazing as it is so far away.there is a sunken village at the bottom of the lake i beleive. in my opinion this is one of the most beautifull places in the country.i had some leaflets while i was there that charted the route that the water took to liverpool but i am not sure where they are, will have a rummage later.

They used to have a 3D video display at Vyrnwy (not sure if it's still there). I know if the water gets low enough you can easily see the remains of Chapel Celyn near Bala.

underneath the dam and something sticking out of the water at said lake

sorry just realised this has nothing to do with the original question,i slipped into sunny weekend away mode

Sorry, getting Alwen and Vyrnwy mixed up aren't I, being next to each other I used to assume they were piped together.

Easy to get confused - my speciality !!

The Vyrnwy Aqueduct goes from said dam to Prescot Reservoirs. It crosses under the Mersey at NGR SJ553844 at a location marked on some large scale maps as "Moore". This is the obvious pinch point where the Mersey is at its narrowest point.

The pipes from Vyrnwy are carried in a cast iron segmented tunnel under the ship canal and river. The access points are obvious if you care to stroll alongside the canal from Runcorn for a couple of miles. They are VERY secure and alarmed up to the hilt. Just DON'T even think about it !

The precise route of the pipeline was marked on OS maps until the 60's when certain Welsh factions decided to blow up various bits of said pipeline. The routes of all aqueducts slipped off maps after that. Funny that ??

The Alwen Aqueduct crosses under the Dee navigation channel at Connahs Quay (sorry, can't find map so no NGR) Again this is in a cast iron segmented tunnel about 50'deep. Two very nice cast iron cupolas mark the shafts down to the tunnel. Pipes within tunnel carry water to the Wirral. This tunnel was driven through running sand and silt in the 1920's. The tunnellers had to work under compressed air to keep the river/mud/crud from coming in to say hello. Had to pass through air locks and decompression etc. Tunnel also carried HV cables to Summers's Iron Works as well.

Sorry, have droned on so much. I also realise I think I have spouted some of this before. Many apols. !!

Hey !! Wake up at the back !!!!!!!

Excellent bit of info. Thanks Pinzgauer. Do you know if the Alwen tunnel is still used for water?

http://www.youtube.com/watch?v=GuxxKRh6dHk

As far as I know, the Alwen (Dee) Tunnel is still in use. Someone on here said a while back that parts of the pipeline on the Wirral itself are now "dry". Water for certain areas now coming from the Dee extraction etc. Another much shorter tunnel, the Bwlch Tunnel, carries the route under the top of the hill on the Mold-Ruthin road. Next door to the Clwyd Gate Hotel.

The video pics of some of the infrastructure are good. Have visited a lot of them over the years with my "Mr Nosey" hat on !

At one time they had a pole route/telephone line following faithfully the whole pipe route. The route was regularly walked by Lengthsmen on the lookout for greener than normal vegetation ie. leaks. They would climb up the nearest pole, presumably using climbing irons, clip into the line and alert whoever !

The last poles were taken down in the 70's I think. Telemetry can detect pressure drop/leaks easily these days. Also they use these flying egg whisk things now to survey the route. It's called progress !

Dont forget the bacteria that infected all the water course above rhythin and the residents had to boil there water. The bwlch tunnel can be seen in the garden of a welsh water owned shabby house just before you hit the brow of the hill at clwyd gate.
There are a few big grids and a tank.... i presume a gun turret in the bedroom as well.

The small triple prongs that stick up in the lawn, along with the "Minen" warning signs are a bit off-putting too !

"The Vyrnwy Aqueduct goes from said dam to Prescot Reservoirs. It crosses under the Mersey at NGR SJ553844 at a location marked on some large scale maps as "Moore". This is the obvious pinch point where the Mersey is at its narrowest point."

Sounds about right - I remember going past Moore on the Mersey Ferry Manchester ship canal cruise - I think that it's was a new town built for the workers building the canal and is somewhere between Runcorn and Warrington