The M8 is absolutely no use as a diversion.
Tell me about it! It's bloody awful!
It's true that Airdrie-Bathgate provides a reasonable diversionary route between the two cities. I would use it if I needed to travel between the two cities when the main route is closed.
But, in my experience, when the line via Falkirk is closed passenger numbers on the A-B (or for that matter other routes between the East and West) don't rise all that much, and I can only suggest that people are choosing to drive or indeed not travel at all in these times.
There is a widespread perception that the other routes are "slow" and are not used; even though journey times are not that much slower all in all. The road, whilst still a massive pain because of the roadworks, gives the commuters some illusion of control and the comfort of their own car. And it isn't "of absolutely no use" - I've used the M8 quite a bit during the roadworks and whilst it is awful, it's still completely usable (in fact, even in the rush hours, it's still preferable to taking the back roads).
That is where they are going - it may not be logical, but believe me the vast majority of people aren't using diversionary rail routes.
Works have been ongoing for the last few months to add another lane to The A8 between Baillieston and the start of the current M8, with many entry and Exits either closed or being modified.
That's not exactly what they're doing - it's a bit more complicated than just a new lane.
There is a new motorway between Ballieston and Eurocentral bypassing the current M8 - this will be 3 lanes + HS in both directions, with one intermediate junction at Shawhead (which is being redesigned). The existing A8 will be retained as a local access road (for Bargeddie and Carnbroe) and will be diverted to start at a new roundabout in Bargeddie with the A89 - it will be much quieter. East of Eurocentral, there will then be four carriageways of traffic each with two lanes and a HS - the M8 in the centre that will have no exits and the local A8 on the outside which will serve the existing exits. After Newhouse the lanes will merge (potentially a bottleneck) into the existing motorway - it looks like it'll be built to facilitate widening to 3 lanes on the existing M8 but there are no plans or funding for this at present.
This is being done alongside a separate but complimentary scheme to widen the M8/M73/M74 network - there will soon also be an additional lane of traffic from M74 J5 (Raith) through J4, onto the M73, and onto the M8 as far as J10 (Glasgow Fort/Easterhouse) in both directions - with the exception of the relevant junctions there will now be four lanes of traffic in each direction here.
This might give you an idea.
[youtube]0v9vl8d6k88[/youtube]
