Filton Bank 4-tracking visualisation

[Henbury Loop]

If accurate then that is a disaster, this is so important for Bristol in terms of capacity.

I watch eagerly to see how they tackle the viaduct replacement at Stapleton Road/M32 Motorway, it does not look an easy task that is for sure.

 

[snowball]

The 2032 date does not sound to me like an informed and considered opinion, more like somebody giving vent to their pessimism and/or cynicism.

 

[The Planner]

4 tracking for diesel services is Dec 18 as previously noted and is a "has to happen" from what I hear.

 

[a good off]

4 tracking for diesel services is Dec 18 as previously noted and is a "has to happen" from what I hear.

From an operational view, I can't wait.

 

[snowball]

4 tracking for diesel services is Dec 18 as previously noted and is a "has to happen" from what I hear.

Shown as a regulated output where I linked it in #29, if that's what you mean by a "has to happen".

 

[HowardGWR]

4 tracking for diesel services is Dec 18 as previously noted and is a "has to happen" from what I hear.

That of course is Dec 2018 as opposed to Dec 18th.

 

[HowardGWR]

Looking again at Google Earth at Stapleton Road bridges, the 'main line' one over the M32 seems to narrow towards the station, but when viewed from underneath with Street View, it does not appear so. The first post #1 in this thread has an animation video of the work. It shews replacement of the viaduct, but not the bridge over the M32. I don't understand what " (Down) " is supposed to mean on some of the captions, including this one. Anyone know?

Is the GE (or GM) view from above an optical illusion? I have a natural scepticism towards any new road structure that was built during the 'rail is on the way out' period, as also evidenced by the M5 bridge over the LSWR line at Exeter only allowing for single track.


Anyway, have a look and tell me if I am wrong. They say on the video it's just repair work.

 

[MarkyT]

Looking again at Google Earth at Stapleton Road bridges, the 'main line' one over the M32 seems to narrow towards the station, but when viewed from underneath with Street View, it does not appear so. The first post #1 in this thread has an animation video of the work. It shews replacement of the viaduct, but not the bridge over the M32. I don't understand what " (Down) " is supposed to mean on some of the captions, including this one. Anyone know?

"Down" is probably a reference to the down side or east pair, i.e. the out of use alignment in this case. Perhaps a bit of misunderstanding regarding 'paired by use' vs 'paired by direction'!

Is the GE (or GM) view from above an optical illusion? I have a natural scepticism towards any new road structure that was built during the 'rail is on the way out' period, as also evidenced by the M5 bridge over the LSWR line at Exeter only allowing for single track.

Not an optical illusion on the aerial view, more likely a composition effect pasting up adjacent images. You can often see this evidenced by perspective changes where you see one side of one building, then the opposite side of a nearby one at a join. Major transport routes are often used by GE as join lines.

The M32 bridge was built when the route was still 4 track. Being relatively new I expect the out of use span to be in pretty good condition.

 

[HowardGWR]

Thanks MarkyT. I suspect your penultimate para indeed explains the distortion. Further up the line, the restitution of an embankment near Boiling Wells, is on the eastern (main) side so I imagine that this is what they mean by 'Down' (even though of course there are two 'down').

'Down Main' would have been better, as there is no option in future as to which is Main and which is Relief. That is because some of the old 4 platform layouts such as Lawrence Hill, and Ashley Hill are not to be restored.

Is Stapleton Road to be restored to 4 platforms? I had the impression it would be and of course Filton Abbey will be 4 platforms.

 

[4973]

Thanks MarkyT.

Is Stapleton Road to be restored to 4 platforms? I had the impression it would be and of course Filton Abbey will be 4 platforms.

I was at Abbey Wood earlier in the week. There is a lot of clearance going on on the Avonmouth side including all of the bank alongside the platforms, along with some digging of holes and trenches, but they didn't look much like the start of a 4th road and Platform.

Might just be early days though.

 

[jj1314]

Is the GE (or GM) view from above an optical illusion? I have a natural scepticism towards any new road structure that was built during the 'rail is on the way out' period, as also evidenced by the M5 bridge over the LSWR line at Exeter only allowing for single track.


Anyway, have a look and tell me if I am wrong. They say on the video it's just repair work.

I had a look in Google Earth Pro and using the 'historical imagery' slider, explored a few of the images from further back. It definitely does narrow from north to south.

If you explore Google Street View and (carefully; it glitches!) pan up you can see the bridge decks all but touch at the northern extent and gradually widen to the southern end.

Following the trackbed south, it does appear surplus room for a double track alignment, though. Not knowing the context/history I'd suggest the eastern deck probably included room for a crossover from the western pair.

 

[NorthernSpirit]

Is Stapleton Road to be restored to 4 platforms? I had the impression it would be and of course Filton Abbey will be 4 platforms.[/QUOTE]

I suspect that Lawrence Hill and Stapleton Road would be retained as two platforms with slow lines serving them and the fast lines through the middle - but I could be wrong.

As for the Severn Beach Line, I do believe that the second platform at Redland is still there so extending the Clifton Down Loop to Redland (and eventually to Dr Day's Jn) may improve the puntuality on the route. It was mentioned elsewhere that the Severn Beach services would be nailed onto the Portishead services.

 

[Stompehh]

I thought the slow lines would be together on the west side, serving the Severn Beach line and stoppers towards South Wales, and the fasts would be on the east, serving XC trains and the London via Parkway services?

 

[Hellzapoppin]

I was at Abbey Wood earlier in the week. There is a lot of clearance going on on the Avonmouth side including all of the bank alongside the platforms, along with some digging of holes and trenches, but they didn't look much like the start of a 4th road and Platform.

Might just be early days though.

It is indeed early days, at the moment access in the area of Stanley Farm bridge is needed for the Horfield cutting works, it would be difficult if not impossible to manage access in both directions. The trenches are to find the redundant cables which were installed in the 1950s, once they're found they will be cut and recorded ready for the main works to start.

 

[D1009]

I suspect that Lawrence Hill and Stapleton Road would be retained as two platforms with slow lines serving them and the fast lines through the middle - but I could be wrong.

Not through the middle, the plan when I worked on the scheme 5 years ago was the existing platforms will remain, with the two main lines going to the east of them where they used to be, also the line speed on the mains is going up to 90 between Filton Abbey Wood and somewhere around Stapleton Road.

 

[swt_passenger]

I thought the slow lines would be together on the west side, serving the Severn Beach line and stoppers towards South Wales, and the fasts would be on the east, serving XC trains and the London via Parkway services?

That's also firmly hinted at in the original video "fly through", where the trains are running on a paired by use layout; i.e. u/d/u/d...

 

[HowardGWR]

Yes, in the pre-cutback era, there were switches and crossings north of Stapleton Road from main (the eastern lines) to relief. The reason was historically, the needs of coal traffic from South Wales to the southern ports, through Salisbury. These trains used the avoiding line at Dr Days to head east to Bath, so they switched over to the eastern side and vice versa in reverse with the empties. The pax trains from South Wales to Portsmouth and Brighton did so too, which is why Stapleton Road was a relatively major station, as those trains stopped there to offload Bristol pax, who would get a bus to local destinations or a Severn Beach local to get to Temple Meads to make their connections.

Fast trains to Pad (Bristolian for example) kept to the eastern side,as they needed to take the Badminton line. So the eastern side at various points was used by both the slowest and the fastest trains! Of course, the trains that would equate to XC ones kept to whichever line their own company (or Region) provided, so GWR / WR South West to North trains went via Severn Tunnel, whereas the MR /LMR ones had already turned off through Barrow Road and crossed over the WR and then dived under it near Yate (two GSJs as we now call them), the absence of which has led to the increased traffic on Filton Bank that we now see.

Stapleton Road from the 50s onwards, became a run-down area which is now looking up somewhat. That's why I pondered about four platforms. I don't think this is envisaged, but clearly there is room for them there, if it is felt useful to avoid TM once again in future.

 

[HowardGWR]

I had a look in Google Earth Pro and using the 'historical imagery' slider, explored a few of the images from further back. It definitely does narrow from north to south.

If you explore Google Street View and (carefully; it glitches!) pan up you can see the bridge decks all but touch at the northern extent and gradually widen to the southern end.

Following the trackbed south, it does appear surplus room for a double track alignment, though. Not knowing the context/history I'd suggest the eastern deck probably included room for a crossover from the western pair.

Yes, thanks, that gap is because it always did widen to allow for the four platforms at the station. MarkyT has reminded us that the four tracks were still there when the M32 was built (1970s) and I had forgotten that (or was not conscious of that fact).

Hopefully, one day, the M32 will become a shared space with a tram /train joining there to the main lines, or leaving the lines from Clifton and Filton to go to the city centre. We can but dream.

 

[MarkyT]

Stapleton Road from the 50s onwards, became a run-down area which is now looking up somewhat. That's why I pondered about four platforms. I don't think this is envisaged, but clearly there is room for them there, if it is felt useful to avoid TM once again in future.

I doubt there'll be much call for avoiding TM, at least for regular passenger trains, as it's so easy to reverse a MU at such a major hub!

 

[MarkyT]

Following the trackbed south, it does appear surplus room for a double track alignment, though. Not knowing the context/history I'd suggest the eastern deck probably included room for a crossover from the western pair.

Seeing gas related infrastructure nearby to the east of the railway, I suspected the historic presence of a town gas works and associated sidings, confirmed by early maps. The siding was still there at resignalling in 1970, as can be seen here:

http://www.signallingnotices.org.uk/scans/60/1970 - S 2669 Bristol Stage 6.pdf

I'm convinced the widening of the east span over the M32 at it's north end was to accommodate this siding turnout. The southernmost section of the M-way was not opened until 1975, so that suggests the siding survived until then, although that particular bridge may have been designed or constructed a little earlier given the road's protracted development history. The four track layout remained until the early 1980s, so the eastern span carried trains for less than a decade.

 

[HowardGWR]

Aha, Mark, you clearly are unaware of one of the nicknames for Bristol Rovers who played there in the Eastville Stadium ground, within walking distance of Stapleton Road station. (The gasheads).

NB Wish they still did.

Yes, if you get hold of the photos of the line in the 1930s, you will see how the gasworks sidings left the GW line where you suppose. They then joined the LMS line from Avonmouth further along that itself joined the northward line from TM at Kingswood Junction. So the gasworks were served by both rival lines.

Back fully on topic, I hope the resignalling takes account of the probable future need, mentioned by others here, for the Avonmouth line junction (Narroways Hill) to be a double one and possibly the whole branch.

 

[D1009]

Back fully on topic, I hope the resignalling takes account of the probable future need, mentioned by others here, for the Avonmouth line junction (Narroways Hill) to be a double one and possibly the whole branch.

Little need for a double junction if there's no double track beyond it.

 

[MarkyT]

Little need for a double junction if there's no double track beyond it.

I beg to differ, as a short section of double there could provide a useful refuge for a branch train to leave the main line and wait clear of it for a late running train in the other direction. The first section of single line is about 2.5km long and contains 2 intermediate sections amounting to a running time of about 10 minutes. If a more frequent service than the current awkward 45 minute interval off peak service ever materialises, along with increased frequencies on other routes, then such a measures might become highly desirable. That said I don't believe the resignalling proposes a double junction, although the modern system being installed will be much more practical to adapt in future to incorporate such enhancements than the 1970s equipment there today.

 

[D1009]

I beg to differ, as a short section of double there could provide a useful refuge for a branch train to leave the main line and wait clear of it for a late running train in the other direction. The first section of single line is about 2.5km long and contains 2 intermediate sections amounting to a running time of about 10 minutes. If a more frequent service than the current awkward 45 minute interval off peak service ever materialises, along with increased frequencies on other routes, then such a measures might become highly desirable. That said I don't believe the resignalling proposes a double junction, although the modern system being installed will be much more practical to adapt in future to incorporate such enhancements than the 1970s equipment there today.

A short section of new double track will never wash its face in terms of a business case unless the timetable requires it to be used on a regular basis. If the route is to continue to be mostly single track, it makes far more sense for trains to pass at stations, rather than the situation you currently have at Tisbury, for example. The Severn Beach service definitely needs to be improved, but I'm not convinced a short section of double track at Narroways Hill is the best way to spend whatever money is required to achieve that objective.

 

[HowardGWR]

Coincidentally the project is in the local news today.
http://www.bristolpost.co.uk/18-mon...-is-replaced/story-30178470-detail/story.html

A busy Bristol road will be closed – mostly on Saturday and Sunday nights – for 18 MONTHS while an ageing railway viaduct is replaced.

The work on the Stapleton Road viaduct is not expected to be completed until November, 2018.

Most of the closures will be on Saturday and Sunday nights but the road will also be closed every night from Saturday, March 18 until Saturday, March 25 between 10pm and 6am while ballast is cleared from the site.

There is also a photo in the article.

 

[MarkyT]

A short section of new double track will never wash its face in terms of a business case unless the timetable requires it to be used on a regular basis. If the route is to continue to be mostly single track, it makes far more sense for trains to pass at stations, rather than the situation you currently have at Tisbury, for example. The Severn Beach service definitely needs to be improved, but I'm not convinced a short section of double track at Narroways Hill is the best way to spend whatever money is required to achieve that objective.

I agree generally that trains should be timed normally to pass at stations and with respect to the junction layout in this case with current service levels. The 4-tracking will enable bypassing of any short term congestion at the junction anyway via the east pair for other services not stopping at Stapleton Rd. That's an improvement on today. An additional platform face on the middle island against the new up fast could provide some extra flexibility in this respect, with no additional access requirements.

<OT>As to Tisbury I'm sure BR would have much preferred to build that loop in the station but previous short sighted land disposal decisions made that impossible. Perhaps the best solution now would be to relocate the station with two new platforms at the loop, saving 4 minutes in the down direction. The loop could also be extended dynamically a mile or so in either direction to provide a little late running resilience and improve run-in speed, Axminster style.</OT>

 

[Sean Emmett]

A short section of new double track will never wash its face in terms of a business case unless the timetable requires it to be used on a regular basis. If the route is to continue to be mostly single track, it makes far more sense for trains to pass at stations, rather than the situation you currently have at Tisbury, for example. The Severn Beach service definitely needs to be improved, but I'm not convinced a short section of double track at Narroways Hill is the best way to spend whatever money is required to achieve that objective.

Metro West Phase 1 proposals envisage extra rolling stock as the most cost effective option in the medium term to achieve half-hourly service to Avonmouth, rather than double-tracking between Narroways Jn and Clifton Down .

 

[MarkyT]

Metro West Phase 1 proposals envisage extra rolling stock as the most cost effective option in the medium term to achieve half-hourly service to Avonmouth, rather than double-tracking between Narroways Jn and Clifton Down .

That would be particularly expensive as reinstated platforms at the intermediate stations would need modern standards of access.

 

[4973]

I doubt there'll be much call for avoiding TM, at least for regular passenger trains, as it's so easy to reverse a MU at such a major hub!

I believe that the only service to regularly avoid TM was the Portsmouth(+Brighton)-Cardiff, and that was largely as it had had a loco change at Salisbury and reversal would involve another one. Horribly slow train, one of the few that made a mandatory stop at Dilton Marsh.

If I recall correctly it used Platform 1 at Newport (High Street) and the relief line between Newport and Cardiff.

 

[59CosG95]

<OT>As to Tisbury I'm sure BR would have much preferred to build that loop in the station but previous short sighted land disposal decisions made that impossible. Perhaps the best solution now would be to relocate the station with two new platforms at the loop, saving 4 minutes in the down direction. The loop could also be extended dynamically a mile or so in either direction to provide a little late running resilience and improve run-in speed, Axminster style.</OT>

More OT: Seeing as most of the land opposite Tisbury is, to my knowledge, unoccupied and rundown, perhaps the case could be made for extending the loop sufficiently to restore the Down platform? I certainly wouldn't be averse to such an idea!


Anyhow, back to the Filton matter.