South Wales 'Metro' updates

[Richard Scott]

At the same time, how much of that has been to events out of their control? Covid, the high inflation rate, previously unknown issues found during works, local residents objecting to bridges, the removal of the pacers before new rolling stock was available to replace them, the previous underfunding of the franchise and infrastructure etc etc

Same is true of many projects but seems people pick and choose on which ones to moan about and which ones they make excuses for depending on political persuasion of the body funding it?

 

[Dr Day]

At the same time, how much of that has been to events out of their control? Covid, the high inflation rate, previously unknown issues found during works, local residents objecting to bridges, the removal of the pacers before new rolling stock was available to replace them, the previous underfunding of the franchise and infrastructure etc etc

Risk management is a big part of project management. Not my area of expertise, but would suggest all of these are risks which, to varying degrees, could have been identified and factored into the budget/programme. Global pandemic probably carried a low likelihood and may not have been on the original risk register, but something like unknown ground conditions or inflation arguably should have been. So not necessarily things within the project sponsor's control, but things they should have taken a view on early in the process and added contingency for (both time and money) else accepted as a risk they were prepared to take.

 

[Last Hurrah]

The tram proposal doesn't need that much extra in terms of distance, from the station car park to after the road bridge on Herbert Street is under 750m. So with an allowance for a suitable length of ramp to match the height of the current line on its embankment something like 1km of new track. Or 2km of single track length if it is to be a double line.

The cost is going to be in extending Cardiff Central with new platforms at the level of the car park (in reality building a new tram station that happens to be adjacent to the current mainline one.)

Then the cost of getting the tracks across Callaghan square in a way that doesn't absolutely destroy traffic flow or have traffic impede the trams so they don't delay other services on the branch coming from Queen St.

One of the tram lines in Sheffield, near the mainline station, crosses a main road on a viaduct, towards Sheffield city centre

Couldn’t the 750 meters or so from Herbert St bridge to Central station be on a viaduct, which will negate the need for a ramp and will enable 2 tram platforms to be built adjacent to platform 8 at the requisite height

 

[AdamWW]

Risk management is a big part of project management. Not my area of expertise, but would suggest all of these are risks which, to varying degrees, could have been identified and factored into the budget/programme. Global pandemic probably carried a low likelihood and may not have been on the original risk register, but something like unknown ground conditions or inflation arguably should have been. So not necessarily things within the project sponsor's control, but things they should have taken a view on early in the process and added contingency for (both time and money) else accepted as a risk they were prepared to take.

I'm not sure what could have been done about inflation. Budgets have to be based on realistic expectations and when this project started inflation was low and expected to remain that way. I don't think contingency in case inflation unexpectedly went up to 10% during the timescale of the project (itself increased due to the pandemic) would have been reasonable.

 

[tomos dafis]

Any chance you can share a link to said maps/plans please? Been unable to find them on here

Map attached in post #4660 25/06/23 this thread - lots of detail, not just planned wiring, but includes planned new station toilets - they appear more sparse than I remember in the impression I formed a while back from replies given to questions about lack of on-train toilets on the tram trains - greater frequency+lots more station toilets was to mean passengers could hop off, use a station loo then catch the next train only 15 minutes later - was quite a while ago now so can't remember who from WG or TFW said it or where, press or TV.

 

[PaulHarding150]

Couldn’t the 750 meters or so from Herbert St bridge to Central station be on a viaduct, which will negate the need for a ramp and will enable 2 tram platforms to be built adjacent to platform 8 at the requisite height

It could but…

- it would cost a lot more.
- it could limit any expansion further west
- the network will at some point extend further using on street running, so it might as well do it now, rather than build a ridiculously expensive viaduct at the grand hight of 6-7m.

 

[Bald Rick]

Global pandemic probably carried a low likelihood and may not have been on the original risk register, but something like unknown ground conditions or inflation arguably should have been. So not necessarily things within the project sponsor's control, but things they should have taken a view on early in the process and added contingency for (both time and money) else accepted as a risk they were prepared to take.

I’ve never seen a railway project risk register with “Global Pandemic” on it.

Inflation and unforeseen ground conditions are on just about every one, though. Some inflation will be priced in, and inflation above expectations will be risked in. However risk assessments do not result in a contingency provision that covers all the possible risk - that’s the point of doing them. There will be no project, anywhere, that has fully priced in the inflation we have seen the last couple of years.

 

[stuu]

Map attached in post #4660 25/06/23 this thread - lots of detail, not just planned wiring, but includes planned new station toilets - they appear more sparse than I remember in the impression I formed a while back from replies given to questions about lack of on-train toilets on the tram trains - greater frequency+lots more station toilets was to mean passengers could hop off, use a station loo then catch the next train only 15 minutes later - was quite a while ago now so can't remember who from WG or TFW said it or where, press or TV.

You are mistaken. Compared the 2020 plan, there are now more toilets planned (Bute Town, Heath High Level and Cryws Road). There may have been an earlier iteration with more though

 

[AdamWW]

You are mistaken. Compared the 2020 plan, there are now more toilets planned (Bute Town, Heath High Level and Cryws Road).

Interesting since Heath (and Crwys Road) are/will be on the Rhymney Line and therefore will be served by trains with toilets.

 

[positron]

You are mistaken. Compared the 2020 plan, there are now more toilets planned (Bute Town, Heath High Level and Cryws Road). There may have been an earlier iteration with more though

Which map is this based off? because the one from 2022 shows those stations as all having lifts but no toilets, though I'll admit the symbol is a pretty odd choice (man and a women in an outlined box with some small arrows above). In fact the only stations on the Rhymney line shown to have toilets are Cardiff Central, Queen Street and Caerphilly.

 

[Dai Corner]

Which map is this based off? because the one from 2022 shows those stations as all having lifts but no toilets, though I'll admit the symbol is a pretty odd choice (man and a women in an outlined box with some small arrows above). In fact the only stations on the Rhymney line shown to have toilets are Cardiff Central, Queen Street and Caerphilly.

Last time I was at Caerphilly, the only toilets were a short walk from the station and managed by the local taxi drivers association, not TfW.

 

[positron]

Last time I was at Caerphilly, the only toilets were a short walk from the station and managed by the local taxi drivers association, not TfW.

I should have clarified the Caerphilly ones are additional ones being added as part of the metro works.

You are mistaken. Compared the 2020 plan, there are now more toilets planned (Bute Town, Heath High Level and Cryws Road). There may have been an earlier iteration with more though

Stations with planned toilets 2022 edition:
Treherbert
Tonypandy
Aberdare
Merthyr Tydfil
Abercynon
Pontypridd (existing)
Radyr (existing)
Cardiff Central (existing)
Cardiff Queen Street (existing)
Caerphilly
Barry (existing)

Additional stations that were planned to have toilets in the 2019 version:
Coryton
Bargoed
Ystrad mynach

Thankfully the descoped stations will all be served by Flirts with toilets.

 

[The exile]

Additional stations that were planned to have toilets in the 2019 version:
Coryton
Bargoed
Ystrad mynach

Thankfully the descoped stations will all be served by Flirts with toilets.

Presumably that’s why they’ve been descoped.

 

[geoffk]

Am I correct in thinking that the tram-trains can't run through Central to Barry or Penarth as those lines are still owned by Network Rail, whereas the valley lines proper are now owned by the Welsh Govt?

 

[AdamWW]

Am I correct in thinking that the tram-trains can't run through Central to Barry or Penarth as those lines are still owned by Network Rail, whereas the valley lines proper are now owned by the Welsh Govt?

I do not believe there are plans for them to run south of Central.

However they will still run over Network Rail metals through Central (but not under overhead wires).

 

[Signal_Box]

Indeed, the S Wales metro is already behind schedule and over budget apparently, but then so also was the original Edinburgh tram airport to city centre by a. considerable margin as pointed out. The Crossrail project in London was also over budget and significantly late opening. So the WG is maybe unfairly singled out as incompetent in the context of delivering infrastructure late and over initial costing.
In terms of buying tram trains just to allow extension further into the Bay and to connect the latter to Cardiff Central, I cannot but help thinking that investing in new modern clean frequent electric buses from the rear of Central station to and around the Bay area was a viable and quicker alternative, leaving all the core valley lines with new replacement heavy rail vehicles like the Rhymney line, though others may find flaws in this idea.
New heavy rail vehicles would all have toilets unlike the tram trains - the idea that all station would be equipped with toilets to obviate the need for this seems not to be materialising according to the latest maps of the plans recently shared on here.
I hesitate to reference the airport in a rail forum but I gently point out that the WG bought it as it was already heavily loss making at the time and being neglected by the previous private owners, though it is accepted that its fortunes have not improved and not for the first time some company 'saw the WG coming' and saw a chance to squeeze the taxpayer.


I agree entirely on that point. I just wish people could just engage with the issues as they see them without ridicule and name calling.
However I share the great disappointment of others at how poorly TFW has managed the delivery of the much trumpeted improvements including the metro. Other threads outline the debacle of the Borderlands line and the use of short formed 150's on long distance routes. In terms of the core valleys upgrade, while some blockades were inevitable passengers were led to believe that much of the disruption was to be late evening and weekends. People in Rhondda were not told until very late they were to lose their trains completely for half a year, and passengers on Merthyr and Aberdare lines have endured longer total blockades than notified, with one station on the Merthyr branch now out of action for an extended period - if planning consent was needed it should have been applied for earlier, if not needed then why apply and incur an unnecessary delay.

Tell you what, I’ll make a little bet with you…

I’ll give you £50 if a tram runs on the road network within Cardiff City limits by, I’ll be generous 01-01-30.

To clarify, a tram runs beyond the currently announced minor extension behind the current Cardiff bay heavy rail limit.

I’m that confident it’s all fantasy, there’ll be no trams before 2030 if at all.

Am I correct in thinking that the tram-trains can't run through Central to Barry or Penarth as those lines are still owned by Network Rail, whereas the valley lines proper are now owned by the Welsh Govt?

That is correct there are also operational rules regards to the trans running on heavy rail proper which excludes the use outside a tight corridor between Ninian Park and Queen Street via Central.

 

[AdamWW]

To clarify, a tram runs beyond the currently announced minor extension behind the current Cardiff bay heavy rail limit.

The line to the Bay may be built to heavy rail standards but it will be running on line of sight operation, i.e. to tramway rules.

(Is there actuallly any advantage to that? I don't know but I can imagine that it would help during disruption being able to let more trains onto the branch than would otherwise be possible).

 

[edwin_m]

The line to the Bay may be built to heavy rail standards but it will be running on line of sight operation, i.e. to tramway rules.

(Is there actuallly any advantage to that? I don't know but I can imagine that it would help during disruption being able to let more trains onto the branch than would otherwise be possible).

You only need signalling at tramway or road junctions - and although the aspects look different it's similar to road traffic lights rather than high-integrity (=much more expensive) railway signalling.

Pedestrians and road vehicles can cross the track on the level, because the tram driver is "driving on sight" just like a bus, looking out for obstructions and being able to stop if they see one. Cyclists can also do so even with the large grooves needed to take railway wheels, as long as the crossing is close to right angles.

 

[AdamWW]

You only need signalling at tramway or road junctions - and although the aspects look different it's similar to road traffic lights rather than high-integrity (=much more expensive) railway signalling.

Pedestrians and road vehicles can cross the track on the level, because the tram driver is "driving on sight" just like a bus, looking out for obstructions and being able to stop if they see one. Cyclists can also do so even with the large grooves needed to take railway wheels, as long as the crossing is close to right angles.

Yes indeed (and also you don't even need ugly security fencing all along the track) but I just meant it wasn't so clear what the advantages are from converting this short section of track to line of sight operation when it currently runs under conventional railway signalling.

Maybe they can add some foot crossings but I think the line is elevated so perhaps not.

 

[geoffk]

Writing as someone not living in South Wales but with a rudimentary knowledge of Cardiff, I would have thought the best route for tram-trains would have been Coryton - Queen Street - Cardiff Bay, a route with closely spaced stations like a tramway, short enough for lack of toilets not to be a problem and offering the possibility of extension not just south into the Bay but also north to a park and ride stop by the M4.

 

[Greybeard33]

Tell you what, I’ll make a little bet with you…

I’ll give you £50 if a tram runs on the road network within Cardiff City limits by, I’ll be generous 01-01-30.

To clarify, a tram runs beyond the currently announced minor extension behind the current Cardiff bay heavy rail limit.

I’m that confident it’s all fantasy, there’ll be no trams before 2030 if at all.



That is correct there are also operational rules regards to the trans running on heavy rail proper which excludes the use outside a tight corridor between Ninian Park and Queen Street via Central.

I am not convinced that TfW/WG have properly thought through the issues of wheel profile, platform height and power supply, regarding future on-street extensions of the tram-trains.

• The 398s currently have the standard heavy rail wheel profile with thick flanges. While it is possible to get grooved rail with a groove that is wide enough and deep enough to take these flanges, that would not be acceptable for embedded track along a public highway (other than level crossings to access a reserved tramway). Too hazardous to cyclists and pedestrians. But the special tram-train wheel profile, used on the Sheffield 399s, would require raised check rails to be fitted to all the heavy rail switches and crossings on the existing tram-train routes. A big additional investment.
• On-street platforms would have to be ~900mm high, as on Manchester Metrolink, to match the tram-train floor height. While this is feasible, the stations have a much larger footprint than stops for normal low floor trams/tram-trains such as the 399s. This makes stop siting more challenging/costly.
• 25kV OLE is a no-no on-street in the UK. But, unlike the Sheffield 399s, the 398s have not been specified with dual voltage capability and so cannot use 750V DC tramway OLE. I imagine retrospective conversion to dual voltage would be costly. But I believe the range on batteries is quite short, just sufficient to traverse the gaps in the discontinuous electrification of the existing lines, and so would restrict the length of on-street extensions.

 

[positron]

I get the impression based on all that I've read that it's less about pure tram running capabilities and more about making future extensions cheaper. For example, Aberdare to Hirwaun, and the North West Corridor could avoid issues with level crossings. Any Coryton (I know this is currently heavy rail) or Penarth extensions could be done cheaper. Even the talk of moving the Merthyr Tydfil railway station would be more feasible with the ability to build to less restrictive standards.

Writing as someone not living in South Wales but with a rudimentary knowledge of Cardiff, I would have thought the best route for tram-trains would have been Coryton - Queen Street - Cardiff Bay, a route with closely spaced stations like a tramway, short enough for lack of toilets not to be a problem and offering the possibility of extension not just south into the Bay but also north to a park and ride stop by the M4.

It seems the long term aim is to use tram trains on the coryton and Penarth routes, at least Mark Barry certainly hopes so.

I suspect if a Coryton project beyond electrification ever gets rescoped it would probably involve utilising tram-train technology. Probably tied into improvements to Cardiff west junction that would allow higher frequency to the Vale which would utilise the spare 3 car flirt units.

 

[MikePJ]

Am I correct in thinking that the tram-trains can't run through Central to Barry or Penarth as those lines are still owned by Network Rail, whereas the valley lines proper are now owned by the Welsh Govt?

It's a matter of power supply. The 398s only have fairly small batteries, so need to be used on a route that is predominantly wired. Installing wires on the Penarth and Barry lines (and indeed through Central) would have to be done by Network Rail, and Welsh Government would have to pay for it. WG is paying for infrastructure enhancements, like dualling of part of the Penarth branch, so this isn't out of the question, but NR may demand that the wiring fully complies with existing standards rather than the discontinuous system that's being used on the Core Valley Lines.

 

[geoffk]

It's a matter of power supply. The 398s only have fairly small batteries, so need to be used on a route that is predominantly wired. Installing wires on the Penarth and Barry lines (and indeed through Central) would have to be done by Network Rail, and Welsh Government would have to pay for it. WG is paying for infrastructure enhancements, like dualling of part of the Penarth branch, so this isn't out of the question, but NR may demand that the wiring fully complies with existing standards rather than the discontinuous system that's being used on the Core Valley Lines.

Thanks for the explanation.

 

[MikePJ]

I am not convinced that TfW/WG have properly thought through the issues of wheel profile, platform height and power supply, regarding future on-street extensions of the tram-trains.

• 25kV OLE is a no-no on-street in the UK. But, unlike the Sheffield 399s, the 398s have not been specified with dual voltage capability and so cannot use 750V DC tramway OLE. I imagine retrospective conversion to dual voltage would be costly. But I believe the range on batteries is quite short, just sufficient to traverse the gaps in the discontinuous electrification of the existing lines, and so would restrict the length of on-street extensions.

There's an article here saying that there's some discussion of "opportunity charging" - short wired sections [EDIT -this is actually DC charging that the units already have some provision to accept] that are off the street - to help top up the batteries. For the reasons you outline I think actual street running will be constrained to quite short sections, but there will be a lot of off-street tramway (e.g. grass track, roadside, or pedestrian-area tramway). Design of modern light rail generally involves trying to minimise actual street running in mixed traffic wherever possible because road traffic will delay trams and is a big risk for accidents. But a tramway is still much cheaper to build, and easier to blend into the local environment, than a fenced and secure railway, even if it does not actually run on the street.

Yes indeed (and also you don't even need ugly security fencing all along the track) but I just meant it wasn't so clear what the advantages are from converting this short section of track to line of sight operation when it currently runs under conventional railway signalling.

Maybe they can add some foot crossings but I think the line is elevated so perhaps not.

The existing signalling (correct me if I'm wrong) is that only one train is allowed on the branch at any one time. As the line is being dualled, a new station is being added at Butetown/Loudon Square, and the expectation is to run a more frequent service, the signalling would have to be significantly upgraded to facilitate this. Moving to line-of-sight eliminates a lot of the associated cost, as only minimal signalling will be required.

 

[takno]

I get the impression based on all that I've read that it's less about pure tram running capabilities and more about making future extensions cheaper. For example, Aberdare to Hirwaun, and the North West Corridor could avoid issues with level crossings. Any Coryton (I know this is currently heavy rail) or Penarth extensions could be done cheaper. Even the talk of moving the Merthyr Tydfil railway station would be more feasible with the ability to build to less restrictive standards.

It does feel a bit like we are using "light rail" as a way of getting around restrictions on level crossings. You have to start wondering whether it would make more sense to work towards a deviation of the standards which allows level crossings but subject to a maximum speed of 50, strict sighting provisions, and a reduction to 5mph through all stations or something like that. Creating a situation where you get the ability to have level crossings but suddenly have new engineering challenges around wheel profiles and electrification standards seems like biting off one foot to save the other

 

[Greybeard33]

There's an article here saying that there's some discussion of "opportunity charging" - short wired sections [EDIT -this is actually DC charging that the units already have some provision to accept] that are off the street - to help top up the batteries. For the reasons you outline I think actual street running will be constrained to quite short sections, but there will be a lot of off-street tramway (e.g. grass track, roadside, or pedestrian-area tramway). Design of modern light rail generally involves trying to minimise actual street running in mixed traffic wherever possible because road traffic will delay trams and is a big risk for accidents. But a tramway is still much cheaper to build, and easier to blend into the local environment, than a fenced and secure railway, even if it does not actually run on the street.

Interesting, thanks. But if DC opportunity charging was seriously envisaged, why did TfW not specify this capability when the units were originally ordered, rather than just provision for the additional equipment? The Sheffield 399s have 25kV AC capability, including the heavy transformer, even though it will be many years (if ever) before the wiring through Rotherham is converted.

I do not believe that 25kV OLE would be permitted above a grass track or roadside tramway unless it was fenced off from public access to the same standard as a heavy rail line.

 

[edwin_m]

I am not convinced that TfW/WG have properly thought through the issues of wheel profile, platform height and power supply, regarding future on-street extensions of the tram-trains.

• The 398s currently have the standard heavy rail wheel profile with thick flanges. While it is possible to get grooved rail with a groove that is wide enough and deep enough to take these flanges, that would not be acceptable for embedded track along a public highway (other than level crossings to access a reserved tramway). Too hazardous to cyclists and pedestrians. But the special tram-train wheel profile, used on the Sheffield 399s, would require raised check rails to be fitted to all the heavy rail switches and crossings on the existing tram-train routes. A big additional investment.

It ought to be workable provided surfacing is designed to discourage random use by pedestrians and cyclists, except at perpendicular crossing paths (please don't call them level crossings, as they are not considered such at tramways and don't require any of the measures usually associated with them). Tramway section built with the large grooves would still be useable if the wheel profile was changed to tram-train in future, except that any grooved rail points would need modification or replacement. But the new sections might just be built with ballasted track and ungrooved rail, which is cheaper anyway.

On-street platforms would have to be ~900mm high, as on Manchester Metrolink, to match the tram-train floor height. While this is feasible, the stations have a much larger footprint than stops for normal low floor trams/tram-trains such as the 399s. This makes stop siting more challenging/costly.

But the alternative would be to provide dual height platforms where they are shared with other rolling stock, which would severely hit capacity at Central and Queen Street. Or go for tram-trains on all routes through these stations and convert every other station to low floor. Any new high-floor platforms are likely to be in "new" urban areas where they are less difficult to integrate, not in confined existing streetscapes.

25kV OLE is a no-no on-street in the UK. But, unlike the Sheffield 399s, the 398s have not been specified with dual voltage capability and so cannot use 750V DC tramway OLE. I imagine retrospective conversion to dual voltage would be costly. But I believe the range on batteries is quite short, just sufficient to traverse the gaps in the discontinuous electrification of the existing lines, and so would restrict the length of on-street extensions.

The tram-train vehicle is a variation on a design used in Karlsruhe (dual 15kV/750V) and Sheffield (750V with unused capability for 25kV), so may be relatively easy to convert to 750V if that becomes necessary in future.

It does feel a bit like we are using "light rail" as a way of getting around restrictions on level crossings. You have to start wondering whether it would make more sense to work towards a deviation of the standards which allows level crossings but subject to a maximum speed of 50, strict sighting provisions, and a reduction to 5mph through all stations or something like that. Creating a situation where you get the ability to have level crossings but suddenly have new engineering challenges around wheel profiles and electrification standards seems like biting off one foot to save the other

The wheel profile and electrification challenges are hypothetical situations that might arise with some future extension, and as I've outlined above solutions are likely to be available if that ever happens.

The major hazard mitigation at tramway crossings compared with railway level crossings is the drive on sight principle, where the driver should be going slowly enough to stop short of any obstruction using only service brake. There is also the hazard brake which is over double the deceleration rate of trains, and can be used if an obstruction unexpectedly moves into the path of the tram. I do agree it's an interesting idea to consider some of this for crossings on railway sections, but it might require the trains also to have these hazard brakes and other features such as much better driver field of view.

 

[javelin]

I am not convinced that TfW/WG have properly thought through the issues of wheel profile, platform height and power supply, regarding future on-street extensions of the tram-trains.

• The 398s currently have the standard heavy rail wheel profile with thick flanges. While it is possible to get grooved rail with a groove that is wide enough and deep enough to take these flanges, that would not be acceptable for embedded track along a public highway (other than level crossings to access a reserved tramway). Too hazardous to cyclists and pedestrians. But the special tram-train wheel profile, used on the Sheffield 399s, would require raised check rails to be fitted to all the heavy rail switches and crossings on the existing tram-train routes. A big additional investment.

Sheffield required a particularly special tram-train wheel profile because its existing Supertram rail profile was only ever designed for typical tram wheels. The same is true for the Croydon, Nottingham and Birmingham systems. Its the retrofitting that is the main problem.

Manchester Metrolink on the other hand has used a modified P8 heavy rail wheel profile instead of a DIN from the very beginning, because it was designed to reuse heavy rail alignments. Metrolink just used embedded track with wide enough grooves from the start.

As it will be a completely new system and not a retrofit, the street running sections in Cardiff can use Metrolink-like embedded rails designed for modified P8s from the beginning. There's no need to reinvent the wheel (profile).

• On-street platforms would have to be ~900mm high, as on Manchester Metrolink, to match the tram-train floor height. While this is feasible, the stations have a much larger footprint than stops for normal low floor trams/tram-trains such as the 399s. This makes stop siting more challenging/costly.

It is a lot cheaper to build a handful of high platforms in the bay than to lower all the platforms on the valley lines.

 

[edwin_m]

Manchester Metrolink on the other hand has used a modified P8 heavy rail wheel profile instead of a DIN from the very beginning, because it was designed to reuse heavy rail alignments. Metrolink just used embedded track with wide enough grooves from the start.

Metrolink has smaller flanges than standard heavy rail, so had to have raised checkrails on the converted Altrincham and Bury lines, which are still compatible with standard railway wheels and have been used by ballast wagons and even a steam locomotive during engineering works. Embedded (street or quayside) track for heavy rail needs an even bigger groove, sometimes done by just laying a double rail as seen on the Weymouth tramway for example. Glasgow ran heavy rail wagons on its street tramways to serve certain shipyards, but only by slightly narrowing the gauge and having the wagons run on their flange tips.