Great Western Electrification Progress

[SwindonBert]

Certainly room for a third track, looking at those. Not sure about a fourth.

looking at the 4th photo down, left hand side. the nearest steelworks shows a 3rd track would be easily accommodated - but the one above it looks tight for a 3rd one.

 

[swt_passenger]

There was a quick discussion back in November about whether or not Maidenhead Turnback Siding would be used for reversing GWR EMU services.

Crossrail argues it is not part of the National Network. If you go back to around 2010, when this was being planned, Crossrail finished at Maidenhead and the TOC (FGW at the time) was expecting to be operating a diesel service from Reading along the route. During the discussions the TOC said that their preference was for turnback from the platforms because their drivers could easily change ends by walking along the platform. There is not enough room for a safe walkway along the length of the turnback but that didn't bother Crossrail because they knew their stock could be walked through.

The Network Change Notice that was sent out made it clear that the turnback was for Crossrail trains only. In 2014 Crossrail services were extended to Reading but it seems that nobody revisited the requirements at Maidenhead, so the platforms still have turnback facilities and the turnback is still for Crossrail only.

RTT is now suggesting that GWR could be using the turn back from the last week of June and early July onwards.

As an example there's an ECS move here that involves the two separate locations, Maidenhead Reversing Sdgs, and Maidenhead Carriage Sdgs.

http://www.realtimetrains.co.uk/train/P04661/2017/07/05/advanced

 

[59CosG95]

There was a quick discussion back in November about whether or not Maidenhead Turnback Siding would be used for reversing GWR EMU services.



RTT is now suggesting that GWR could be using the turn back from the last week of June and early July onwards.

As an example there's an ECS move here that involves the two separate locations, Maidenhead Reversing Sdgs, and Maidenhead Carriage Sdgs.

http://www.realtimetrains.co.uk/train/P04661/2017/07/05/advanced

That may well be true that GWR will use the turnbacks (I mean, they're there, they may as well be used!), but when Crossrail arrives (or when Reading Depot is connected to the OLE a the east end), I can't see GWR needing to use it after that.

 

[swt_passenger]

That may well be true that GWR will use the turnbacks (I mean, they're there, they may as well be used!), but when Crossrail arrives (or when Reading Depot is connected to the OLE a the east end), I can't see GWR needing to use it after that.

Yes that does seem to be the likeliest long term position, as GW will be running far less services of any type on the reliefs to/from/through Maidenhead.

I was really just highlighting that the earlier proposition, i.e. that it wouldn't be used at all between commissioning and Crossrail full running in 2019, should now be considered highly unlikely.

 

[DidcotDickie]

looking at the 4th photo down, left hand side. the nearest steelworks shows a 3rd track would be easily accommodated - but the one above it looks tight for a 3rd one.

Photo attached I took this morning from the adjacent road bridge. There is plenty of room for a third track under the footbridge but a fourth might be a bit of a squeeze.

It's worth pointing out that there used to be a third track here in the form of an up loop at Uffington which ended just my side of the Autotransformer (ATF) station. This was removed when the long loops between Challow and Wantage Road were reinstated in 1990. The signal controlling the exit from the loop lasted well after the loop was decommissioned and was only removed when the ATF station went in last year!!

Widening the line here to 3 tracks or 4 would require reconstruction of the road bridge from where the picture is taken as the piers are in the way. It would also need reconstruction of Baulking Lane overbridge further east as well as the cuttings in between. Obviously possible but will be very expensive as there are some properties very close to the line here too.

 

[jyte]

Photo attached I took this morning from the adjacent road bridge. There is plenty of room for a third track under the footbridge but a fourth might be a bit of a squeeze.

Great picture, thank you.

I think this has been explained before (I've done a search, couldn't find why) but those masts looks to be a mess of different sizes and heights. Why?

 

[LNW-GW Joint]

Great picture, thank you.
I think this has been explained before (I've done a search, couldn't find why) but those masts looks to be a mess of different sizes and heights. Why?

The masts are generally "lop-sided" because the AT wire is strung at a higher level than the other wires, on one side.
The couple of tall parallel masts on the left will probably be to hold switchgear, which is needed every so often in a length of OHLE.
No doubt all will become clear when the masts are "dressed".

 

[swt_passenger]

At various locations including neutral sections, feeder sections, and at wire run overlaps (at the end of tension lengths) all the extra stuff required such as spring tensioning devices, maintenance switch gear etc are mounted higher than the normal contact wire. So anywhere there is something complicated happening the masts get higher.

On older installations tensioning was nearly always done by running off to the side of the main runs, with for example weights hanging on masts. This didn't require extra height so masts didn't need extending upwards. But the down side (particularly on a four track railway) was that the wire runs to the tension weights had to be threaded diagonally through other lines wiring to go off to one side. Makes a dewirement much more damaging.

 

[HowardGWR]

Your last pic of Uffington (thanks) shews that the footbridge certainly has been made wide enough and the other areas would not be too difficult (I don't see the houses being too close actually). I presume the bridges were made higher but there was no need to alter them otherwise, at present. Of course the original 10 foot broad gauge spacing gives some elbow room too, so perhaps future-proofing has been considered.

 

[DidcotDickie]

Great picture, thank you.

I think this has been explained before (I've done a search, couldn't find why) but those masts looks to be a mess of different sizes and heights. Why?

You're welcome.

To add to what others have posted - most of the masts along the line appear to be overheight in order to provide brackets for supporting the -25kV ATF wire. In the picture the short mast nearest the camera will carry an anchor boom which is used for terminating a set of wire lengths. There's another one the other side of the ATF station which has a bracket to support the boom already fitted. The other shorter masts will support the catenary and contact wires.

The set of overheight masts adjacent to the ATF station (I think there will be four on each side eventually) will support wires which run from the busbars on the ATF station transversely across the tracks (I think these are called 'drapes') and wires from these will feed vertically down to the catenary wires. This is how power is fed from the feeder and ATF stations into the OLE.

Prior to the new footbridge there are two overheight masts which are slightly set back from the track. Looking at other locations, I think these will terminate the ATF wire which is then fed down the mast in a thick insulated cable to ground level and then through trunking under the bridge. On the other side two similar masts will be installed for the reverse configuration.

It all looks rather confusing in the photo but if you travel between Didcot and Reading and look at the completed ATF stations at Cholsey and Pangbourne, the configuration becomes more clear - as does the arrangement for getting the ATF wire under bridges.

 

[DidcotDickie]

Your last pic of Uffington (thanks) shews that the footbridge certainly has been made wide enough and the other areas would not be too difficult (I don't see the houses being too close actually). I presume the bridges were made higher but there was no need to alter them otherwise, at present. Of course the original 10 foot broad gauge spacing gives some elbow room too, so perhaps future-proofing has been considered.

Yes, the footbridge is probably OK and widening the line to 3 or 4 track between Challow and Swindon should be feasible if enough ££ were thrown at it.

Between Challow and Baulking would be quite straightforward, though Baulking overbridge would need replacing and - depending on how much landtake was required to widen the cutting - the house on the north side of the bridge may need to go.

http://www.google.co.uk/maps/@51.61...113.41499&pitch=0&thumbfov=100!7i13312!8i6656

At Uffington, the former station hotel (on far right in Google Streetview link below) is quite close to the existing track and the overbridge would need to be replaced as I mentioned previously.

http://www.google.co.uk/maps/@51.61...4!1sSuwVMEGX3gYloU9LiVnN4g!2e0!7i13312!8i6656

Other overbridges further west would need replacing as would Acorn Bridge over the A420. I don't know if the replacement bridge carrying the B4000 over the line at Shrivenham station was built wide enough for four tracks, but I somehow doubt it!

 

[jyte]

People keep talking about 3-4 tracking and I understand the desire to 'futureproof', but is there any demand for four tracking or a model that shows the need for it within say for instance, a decade or so?

 

[Hellzapoppin]

How many? You would only need a couple of piles for the footbridge (a ROW) at Foxes Wood. You wouldn't need any for a track lowering at Twerton, I would have thought. On the latter, presumably the A4 bridge near Newton St Loe is too low clearance, as well as Twerton tunnel.

Howard, the track is being lowered under the A4 bridge and Twerton tunnel is 9 metres from top of rail to the crown of the tunnel which I'm told is plenty of clearance.

 

[coppercapped]

People keep talking about 3-4 tracking and I understand the desire to 'futureproof', but is there any demand for four tracking or a model that shows the need for it within say for instance, a decade or so?

As long as there are no stations between Didcot and Swindon then the existing two tracks, and occasional passing loop, will be sufficient for the next few years especially now as the coal trains to Didcot 'A' power station no longer run.

However there are continuing noises about re-opening stations to serve local communities which have grown since the 1950s/60s. One such is Grove, near Wantage, on or near the site of the old Wantage Road station; possibly one in the Steventon/Milton area west of Didcot and another serving the eastern side of Swindon placed either at or near Shrivenham or at the point where the Swindon Ring Road (A419) crosses the railway. West of Swindon there are pressure groups pushing for the re-opening of Royal Wootton Bassett and Corsham stations so there may well be a stopping service along the route extended west from Didcot. If this comes to pass then it may well be necessary to, at a minimum, lengthen the passing loops and in the long term extend the four tracks through to Swindon. I have read suggestions that four tracks through to Wootton Bassett junction may well be necessary if, in addition, the service intensity between Swindon and Westbury (and onwards) is increased.

 

[D1009]

People keep talking about 3-4 tracking and I understand the desire to 'futureproof', but is there any demand for four tracking or a model that shows the need for it within say for instance, a decade or so?

You only need four tracking if there are a significant number of trains running at differing speeds. Until very recently there was a substantial flow of coal to Didcot Power Station, which was the reason for the Wantage Road to Challow 4 track section, replacing the loops at Uffington. This has now ceased, so the case for future proofing depends on the potential for substantial freight flows.

 

[Tio Terry]

That may well be true that GWR will use the turnbacks (I mean, they're there, they may as well be used!), but when Crossrail arrives (or when Reading Depot is connected to the OLE a the east end), I can't see GWR needing to use it after that.

Just a minor point. The turnback is designed for a Crossrail turnback for a full length train. Because GWR (FGW actually at the time) said they had no need for it and would only turnback in the platforms, no allowance has been made for anything other than a full length 345. There are no 4 foot markers telling drivers to stop a varying length train, which is what is normally provided in such situations. Originally, FGW stated they would have no use for it because their services consisted of variable length DMU's that may not have been able to walk through - remember there is no trackside walking route. Maybe the requirements should have been reviewed when the decision was taken to extend Crossrail to Reading.

 

[D1009]

They are from earlier works. Not sure about Twerton tunnel, I'm intrigued myself now so I'll ask some questions. Surprised no mention has been made of the works in Bath spa station, certainly more interesting than piling.

Passing through there a few minutes ago, all that seems to have happened so far is the removal of all the track and ballast from the down platform. Presumably things will start in earnest tomorrow when the full block starts.

 

[HowardGWR]

Howard, the track is being lowered under the A4 bridge and Twerton tunnel is 9 metres from top of rail to the crown of the tunnel which I'm told is plenty of clearance.

Thanks very much. I have measured the Foxes Wood and St Annes tunnel elevations by eyeball interpolation and concluded 28ft -30ft high at centre, so I would not have imagined Twerton was different. I imagine Saltford will be the same.

I have this idea that during the 20th Century, some Brunel bridges were replaced with brick ones, being required for road widening, and actually ended up lower, due to being flat instead of humped. Together with ballast being piled up upon ballast, I have conjectured whether these developments led to the work, in many places, being needed for electrification.

 

[Hellzapoppin]

Passing through there a few minutes ago, all that seems to have happened so far is the removal of all the track and ballast from the down platform. Presumably things will start in earnest tomorrow when the full block starts.

The down platform has been widened by 1.5 metres, new 2.5 ton coper units installed on top of concrete riser wall units, new tactiles, complete platform resurfaced, new aco drains installed and the new riser wall tiled. The track on the down side will now be reinstated and the whole exercise repeated on the up platform whilst working bidirectional on the down. So I'd say we've done quite a lot in the past week. Oh and I've appeared on Twitter (what ever that is) along with a few of the team explaining what we've been doing.

 

[HowardGWR]

You only need four tracking if there are a significant number of trains running at differing speeds. Until very recently there was a substantial flow of coal to Didcot Power Station, which was the reason for the Wantage Road to Challow 4 track section, replacing the loops at Uffington. This has now ceased, so the case for future proofing depends on the potential for substantial freight flows.

Yes, but if the stations were reopened between Didcot and Swindon, I believe that 4-tracking is inevitable, or at least reinstatement of all the loops in the stations.

 

[HowardGWR]

The down platform has been widened by 1.5 metres, new 2.5 ton coper units installed on top of concrete riser wall units, new tactiles, complete platform resurfaced, new aco drains installed and the new riser wall tiled. The track on the down side will now be reinstated and the whole exercise repeated on the up platform whilst working bidirectional on the down. So I'd say we've done quite a lot in the past week. Oh and I've appeared on Twitter (what ever that is) along with a few of the team explaining what we've been doing.

We will all be tuning in immediately.

Although a link would be handy. I just got some nice girl who's getting married, she informed us.

 

[Hellzapoppin]

We will all be tuning in immediately.

Not sure when the videos are being put out but let's just say I'm not an A lister just yet. I might be able to compete with lassie in the dialogue stakes but it was good fun anyway.

 

[SamYeager]

If I've got this right then these should be a couple of links to relevant videos:

Bath Spa Upgrade Day 1

Bath Spa Upgrade Day 2

Various pics of work at NetworkRailWest Twitter

 

[Mintona]

Had the down platform at Bath actually been extended at all? It barely fits an HST at the moment. I thought it was having some length added for the IEP trains.

 

[Hellzapoppin]

It will be extended but not as part of this TPOD, too much to do in the time available. Not sure when the planned dates are for that though?

 

[fgwrich]

There will be definite signs of the work just after Easter, travelling down on the down Night Riviera there was a lot of OHLE Works taking place between Langley and the viaduct at Reading, further wires going up and even the HBOC at work on the Down Main / Fast.

 

[jyte]

There will be definite signs of the work just after Easter, travelling down on the down Night Riviera there was a lot of OHLE Works taking place between Langley and the viaduct at Reading, further wires going up and even the HBOC at work on the Down Main / Fast.

I should hope so

It's taking long enough!

 

[hassaanhc]

There will be definite signs of the work just after Easter, travelling down on the down Night Riviera there was a lot of OHLE Works taking place between Langley and the viaduct at Reading, further wires going up and even the HBOC at work on the Down Main / Fast.

Ah, that must have been what I saw crawling through Southall on Wednesday evening around 2220, going to Taplow (according to RTT)

 

[jyte]

https://youtu.be/b4BkpBZPRa0

New NR PR video about 387 testing to Maidenhead.

 

[spark001uk]

When I was passing Langley yesterday, I noticed something on the portal immediately East of the platforms. On the UM there are two orange leads that appear to be across the insulator. Obviously that can't be right, that would short the supply out to the metalwork?

Sorry for pic quality, but it roughly shows their placement.