I’d have thought at the South Hylton end getting under the A19 would be the most significant issue, although it looks as if there’s a footpath subway. South Hylton is at roughly the same level as the local road, I think it’s Hylton Bank? Presumably a level crossing issue in the present climate, but perhaps Metro could still get away with splitting the station either side of the road as at various other locations? Does anyone know if they would be allowed to install new now?
The bridge that's still there under the A19 would only be wide enough for a single track. I'm not sure if this was incorporated into the A19 to get the road over the railway at a time after regular traffic had ceased and it had perhaps become a single track serving a freight objective of some sort, or if it was there to facilitate the bridleway/footpath that the trackbed has now become. Either way, it's also used as a road to access the farm buildings on the eastern side of the A19 - I drove through there last Saturday funny enough!
Installing a new crossing shouldn't be an issue at South Hylton; as it's next to a station most trains will be slowing down / pulling away, the construction would be reinstatement with little alternative routing as opposed to a new build, and barriers with CCTV and obstacle detection would almost certainly be a given. Despite this, splitting the station would likely still be a good option, as it ensures that the vast majority of trains will be accelerating when crossing rather than braking.
I don’t think TWM style high floor light rail vehicles can do street running, they’d need the full skirts and enclosed bogies that a normal tram has.
The current order of high floor units can't do street running, as the skirts are the issue as you mention. These can add a considerable amount of weight. Most modern trams have doors over the couplers too, as this is a potential source of injury/damage in the event of a collision. Since the couplers on the Stadler units will only ever be used for ECS movements or dragging units about in the depot, I'm quite surprised that the design leaves the couplers exposed to be honest, as a big gaping hole at the front of the unit will add a decent amount of aerodynamic drag and it's a somewhat missed opportunity to improve safety at the various open level crossings on the network.
High floor street running also requires a lot of space on streets too, as you have to adhere to minimum platform widths and such, providing access such as stairs or a ramp too. It's for this reason that the vast majority of systems, even overseas, are low floor as the station environment is much easier to integrate into existing street layouts. On the other hand with low floor trams, you can get away with just having a slightly raised kerb on a normal pavement if space is tight - kind of how we do for bus stops on some of the busier routes.
If we ever see trams in Tyne and Wear I'd expect them to be a low floor segregated network, but perhaps with common branding and ticketing shared with Metro. It's possible we could also see some sections of track shared too without stopping, or with some stations rebuilt to have both high and low sections of platform, but there wouldn't be too many cases where this sort of arrangement could offer enough benefit to justify the hassle.
www.transportnortheast.gov.uk
