I don't understand the fetish for a separated light rail system for the South Wales valleys. The service would be worse for journeys from outside the Cardiff area, Cardiff city centre has no space for segregated light rail, it would not be suitable for the Barry line and would cost a lot of time and money to implement.
It's come down to a number of factors.
1. The electrification crisis at Network Rail seemingly rendering them incapable of carrying out any upgrade project competently, on time and on budget
2. The Conservative govt's refusal invest anything in rail infrastructure in Wales, esp since Chris Grayling took over at the DfT
3. The Conservative govt's refusal to hand over responsibility and control of Network Rail in Wales to Welsh Govt to allow Welsh Govt to specify what infrastructure upgrades it would like to see in Wales
4.
Money: The cost of upgrading the Valley lines if heavy rail electrification is chosen. Raising many, many very old bridges, doubling the single line sections up to the heads of the valleys to allow increases in frequency, widening the bridge over Newport Rd to relieve the bottleneck before Queen St, somehow managing to increase capacity with the constraint of the 2 track section between Queen St and Central (which is now impossible to widen without demolishing newly built, albeit some empty, office buildings), the complexities of wiring Caerphilly tunnel.
Although CASR now allows 16tph between Central and Queen St, and there are now 4 platforms available at both Central and Queen St for valley lines services, but as ATW haven't got enough trains to take advantage of the capacity CASR has unlocked, we're still stick at 12tph.
All these factors mean Welsh Govt want to take control of the only bit of rail infrastructure in Wales that they can, which is these 'Core' valley lines north of Cardiff, as it can be a relatively self contained network. Light rail is seen as much cheaper. Although the single track sections north of Abercynon will still be there, and one tram can only occupy a single line section at a time just as one train can.
Taking trams off the network at Cathays so the trams wind their way around the musuem and castle to get to Central station down Westgate street, which is currently choked with buses (which I don't see changing even with the new
mini bus station) is madness. Currently Cathays to Queen St takes 3 minutes maximum. Cathays to Central about 7 minutes. But lets push that time up to 20 - 30 minutes sat in heavy traffic instead.
It currently takes 17 minutes to go from Cogan just outside Cardiff to Cathays on one train. Prof Cole's suggestion would see you having to not just change at Central, but exit the station, walk to get on a tram, then wind your way through central Cardiff's most congested streets, and your journey time at least tripled.
I despair. :cry: