Bristol connections: Metro, Bus Rapid Transit, PTE, ITA and local councils - discussion

[whole diary]

[TonyK]

Indeed so! Those of us (myself included) who thought we heard Theresa Villiers announce Four Track, Now! last year at Temple Meads know better now. To think I introduced a comma into my forum identity in celebration! Premature, it transpires.

I don't know about local politicians just making noises. Someone has to give DafT a heads up that there are problems in the city, and they are the obvious conduit. There must be an awful lot of stuff going to and fro between civil servants and council officers that we don't see, but the politicians locally and nationally must agree a scheme such as this. Evidence of good governance of transport projects will help, which is a bit of a potential problem for Bristol, but I remain confident.

[Red Squirrel]

I think Paul asks a good question: a cynical squirrel might think the politicians were doing what I believe is known as 'grandstanding'. A less-cynical one might concede the possibility that they are all united in recognising the need for a crucial piece of investment.

The devil is in the detail; for example we need to unsure some DaFT^» (Department for Transport - critical sounding abbreviation I discourage - about) ha'p'orth doesn't try to economise on metaphorical tar by doing the job with just three tracks (which might suffice, if you weren't seeking to enhance local services); similarly I hope they are strongly arguing the case for new platforms at Lawrence Hill and Stapleton Rd to add resilience and flexibility.

I think it's fair to say that NR^» (Network Rail - home page) are doing everything they can to ensure that this project is 'shovel ready'. But no shovel will move until the money's committed.

[TonyK]

We don't talk about Three Track, Now any more, he's something of the black sheep of the family. Doesn't even merit an exclamation mark.

You are quite right about four tracks being needed. Three would work now, but we all know how improving a railway leads to passenger growth in a way that none of the models ever predict. All four shiny new tracks will lead into the much-vaunted enterprise zone, which needs a bit of a kick-start, not to mention a revamped Temple Meads. Reopened stations and more services from the existing ones will bring investment all along the routes.

At Stapleton Road and Lawrence Hill, there will be three platforms without any building needed. A fourth platform at each is possible, but not imho necessary. Passive provision can be made without great cost for fourth platforms in the future.

[Red Squirrel]

At Stapleton Road and Lawrence Hill, there will be three platforms without any building needed. A fourth platform at each is possible, but not imho necessary. Passive provision can be made without great cost for fourth platforms in the future.

Is that so? I think work would be needed at both stations to allow trains on the fast lines to stop, not least signalling. A three-platform face solution would presumably require bidirectional capability, which (from what little I understand of these things) could be more expensive than just adding a fourth platform face.

Also we shouldn't assume any existing platforms on the fast lines would survive the civil engineering work, of which there will be plenty at Stapleton Road. Oh, and I forgot to mention Ashley Hill, Horfield and Filton Abbey Wood... if platform faces aren't provided on both pairs of lines, the local service will get the chop whenever there's engineering work or other disruption, won't it?

[TonyK]

The alignments are still there, and now I've looked back at some earlier pictures at Stapleton Road, there are four platforms there.



Lawrence Hill didn't retain its fourth platform:



I would have thought that care would be taken to not damage the existing platforms, not least because they will still be in use for much of the time that it takes to add two new tracks. Signalling is all scheduled for renewal before electrification - what's wrong with a bit of joined-up thinking?

(Sorry - optimism got the better of me again!)

[Chris from Nailsea]

My understanding is that there would be no insuperable problems with reinstating four platforms at Stapleton Road and Lawrence Hill. 

[TonyK]

Mine too. Chris. The same goes for Horfield, although it would need a fair bit of work, and would be a heck of a climb up to Bonville Road:



Ashley Hill has a bend close by, which may prove a problem



To be more accurate, two bends.

[Red Squirrel]

Mine too. Chris. The same goes for Horfield, although it would need a fair bit of work, and would be a heck of a climb up to Bonville Road...

Plenty of room for a DDA^» (Disability Discrimination Act - about)-compliant ramp on the cutting sides, I'd say, though getting to the island platform could be more of a challenge

Really I was just pointing out that there is a need for the local politicians to keep up the pressure to ensure we get what we need for local services - someone in Whitehall could decide to save a few quid in the short term by not providing the additional platform faces, but it would greatly diminish the 'Metro' aspiration.

Ashley Hill has a bend close by, which may prove a problem... ...To be more accurate, two bends.

Or to be even more accurate, it's in the middle of a curve that starts at Narroways and ends just the other side of Muller Road. Anyone know:

(a) What is the minimum radius curve you can build a new station on?
(b) What the radius is at Ashley Hill?

[stuving]

(a) What is the minimum radius curve you can build a new station on?
(b) What the radius is at Ashley Hill?

(a) From GI/RT 7016, 1000m.
(b) Around 1100m, at the apex, from a rough measurement on Google earth.

[TonyK]

(a) From GI/RT 7016, 1000m.
(b) Around 1100m, at the apex, from a rough measurement on Google earth.

Thanks for burning the midnight oil for us, Stuving. Your dedication to engineering excellence knows few bounds!

So no problem at Ashley Hill, then.

On a matter less engineering, but more engineered, a little bird tells me the red-trousered Mayor of Bristol is to plump for Bedminster Bridge - Cumberland Road - Ashton Avenue Bridge for the crap BRT^▸ (Bus Rapid Transit) project. Whilst this is a slight improvement on bulldozing the Harbour Railway for this least vain of all vanity projects, it remains far from a cause for celebration here in FTN Towers. It does, however, mean that the long-awaited Planning Inquiry report and Secretary of State's decision should be out soon, with the inevitable legal challenges soon after.

[Red Squirrel]

(a) What is the minimum radius curve you can build a new station on?
(b) What the radius is at Ashley Hill?

(a) From GI/RT 7016, 1000m.
(b) Around 1100m, at the apex, from a rough measurement on Google earth.

A straight answer to a straight question - thanks, stuving. No hope of a career in politics for you though! 

[stuving]

A straight answer to a straight question - thanks, stuving. No hope of a career in politics for you though! 

Of course, then there are the "but"s ...

What may be a more serious constraint is the minimum widths and clearances now required for new platforms. The basic limit is for 2.5 m from a single face or 4 m between two faces, but in practice those only apply to the ends. The 2.5 m clearance is also needed from either face to anything bigger than a lamp post. Thus for an island platform you need 5 m plus the stairs, except possibly if the only access is off ends.

You can try to add up the various distances, but only some of them are clearly specified:
  Gauge:            1435 mm
  Platform offset  730 mm
  Platform edge to structure 2500mm - but more for high-speed running
  Structure width - probably you need to consult disabled access standards
  Track interval (sixfoot) certainly more than 1968 mm, probably 2000 mm - I can't find a reference value.
See not only GI/RT7016 but also GI/GN7616 for details. Note that the relationship between the standard and the guide is not always obvious.

The lack of a standard figure for track interval is rather odd. There is quite a lot in standards about gauging for vehicles and track layout to fit existing satructures, but to design structures for anything but single track you need a standard value for track interval. Otherwise you need to do a gauging exercise for all possible vehicle combinations, including positioning the track, to specify any structure!

[chuffed]

This is Bristol is quoting an article by Ian Onions saying that the announcement we are all expecting next month may not happen because the business case is not ready. After all the months and months and months of talking up this project , have we all been led up the garden path yet again, only to be confronted by a brick wall ?
 It looks as if we are being softened up to expect disappointment.
Why are Charlotte Leslie, Kerry Mccarthy, Stephen Williams, Jack Lopresti, Chris Skidmore and the invisible man of North Somerset Liam Fox and even Dawn Primarolo not marching into Daft HQ^▸ (Headquarters) every day and making a thundering nuisance of themselves, by presenting a united front and showing how much they are about the Bristol Metro going ahead?  ?. If this was Manchester, the  Northern MP^▸ (Member of Parliament)'s would have had all this done and dusted by now.
If this fails, you will all deserve to lose your seats at the next election, because you will have let down your electorate very badly indeed.

[Red Squirrel]

Well it may not be quite as bad as you suggest - you know journalists, they simplify and then they exaggerate:

A partnership spokeswoman said: "The Greater Bristol Metro is not an all-or-nothing project, which would be opened in one big fanfare. It is a series of projects, some large, some small...

"It will develop like a jigsaw... ^ you could say that some pieces, like the Severn Beach Line, are already in place. All the different bits link together but we need to unlock the limit on the lines by achieving Filton four-tracking and reopening the Portishead line before we can do anything else."

...The WEP spokeswoman said: "The key to the first phase ^ reopening the Portishead line and half-hourly services on the Severn Beach line ^ relies on the four-tracking of Filton Bank to introduce the extra capacity on the local network. This then triggers the next phase so we will not be surprised if they are not included in the document due out in June."

The 'Four Track Friday' event at Stapleton Road a couple of weeks ago was emphatically about requadrification and nothing else - not local electrification, not Portishead, not Henbury Loop. You could argue that it would be better to take all these schemes as a cohesive whole, but that does not appear to be the approach being taken. And actually this does worry me, because surely the requadrification scheme should include the new stations, platforms and signalling required for the 'Metro'; it'll be much more expensive to do this work afterwards, even with passive provision.

[TonyK]

You would think that reporter would know his, er, Onions, but in the name of relentless optimism, I will join Red Squirrel in his view that this is just a bit of journalistic licence, and a very poor quote from one of the dunderheads in the self-perpetuating oligarchy that is West of England Partnership. WEP has done for public transport in the greater Bristol area what Cyril Smith did for indoor hang-gliding. Such public transport as we have within the city is in spite of WEP, not because of it.