Shhh, he's got some youtubers on his side. Everyone knows that beats engineers
Because the engineering challenges of underground stations are considered to be more tractable than the political challenges related to surface stations.
So where does the plan say the NPR tunnels emerge at the Marsden end? There is logic of re-joining the TRU triple track beyond Marsden (as crayoned in posts #54 and #59).
Will it? From the geological reports it sounds like an utter nightmare of a project to fit overhead wiring into a tunnel that has been out of serious use for decades and was never designed for it.
Would it? From aerial/satellite photography "sorting it out" looks to be outright impossible.
I think the only feasible route to do that would be to continue the line of the twin-track western bore across the valley on a 250m long viaduct and into the hillside opposite. A gentle curve inside the hill would line up with the route beyond Marsden, which would allow high-speed running until the kink at Slaithwaite Viaduct. I reckon you would need curves of 1000m radius, which corresponds to a speed of around 125mph. This topograpic map shows the land forms.
Could you not just angle the bore down and emerge below Marsden rather than above it? It's a bit longer yes but it saves having to do heavy engineering on a Pennine hillside.
I'm sure you could. But I think you would have to go under the River Colne. The descent would start so far back that you might just as well construct a new bore entirely, and avoid construction site complications around Diggle. Which is what @Bald Rick is suggesting is now the plan.
www.theconstructionindex.co.uk
It was always more likely to be a new bore.
What's the logic in constructing two stations on opposite sides of the city centre?
Not what I've heard. Mentioned it earlier on the thread. It'll diverge to (Manchester bound) to the right somewhere around where Slaithwaite Hall is.
It's not though is it? Both Crossrail and HS2 have used up significant amounts of urban surface land for works compounds, routeways, supporting buildings like substations and depots, and ventilation shafts and stations. Yes, some of this was already in Network Rail or other public ownership but the rest of it has been found through re-use of brownfield sites, or, where necccesary, demolition and relocation of buildings including through compulsory purchase. It's also not 'politically' too difficult to build new reserved ways for light railways where there used to be general traffic.
We must be talking at cross purposes. Going towards Manchester, that's exactly where I would expect the fast lines to diverge, i.e. before the curve to Marsden station.
