Very well put, Brunstane station is at the complete wrong end of Porty to be attractive to most people, with no direct bus there from the town centre. Even now most folk would never get the train despite it being so much faster into Edinburgh than the 26. In my opinion, completely rebuilding the whole Craigentinny Depot to Portobello Junction section to put a new station in where the old one used to be, while increasing capacity significantly is absolutely worth it in the long term, maybe even nescecarry. However it would be massively expensive, disruptie and time consuming, so I woulldn't be too hopeful.
You'd be spending somewhere between a third and half a billion quid to
marginally increase capacity.
You'd be closing the line from Mussleburgh and Newcraighall to Waverley for potentially several months, during which you'd be limited severely by the capacity of the sub for diversions, and it's lack of wires. Disruption would be, as you said, severe.
Now, there's not much you could actually get out of it this particular scheme without significant enhancements elsewhere. I think you misunderstood me.
This remodeling wouldn't be an enhancement, it'
s the bare minimum. Specifically, the bare minimum that would be necessary to put in a new station with more than two platforms, while maintaining line speed and capacity on the ECML, and enhancing speed over Portobello Jn to the Borders Line.
You need to spend this money on more than two platforms to put in a station that doesn't crater capacity by stopping 3tph on a very busy two track section three miles from Waverley. The capacity you gain by remodelling is about equivalent to the capacity you lose by building the station in the first place.
If you wanted more capacity, this scheme doesn't really do that; at a minimum you'd need to four track some of Wallyford-Drem and remodel the western throat of Waverley, including the tunnels. It's into the realm of diminishing returns, the amount you have to spend for each extra path increases exponentially.
Of course we could do a full feasibility study on this, however I don't think it's necessary. A station would have anywhere between 0.2m - 0.8m annual passengers, depending on how nice you make it, and how big, and what you stop there, and how often trains stop, ect... That's anywhere from a station with basically the same usage as Brunstane, and just as depressing, to spending a lot of money and getting somewhere nice, with more users than Edinburgh Park and Edinburgh Gateway combined.
If you think that spending all this money to build a Portobello station is worth it, then it might be worth it, but I'd humbly suggest that trams might be a better investment.
