If we are worrying about the disruption caused by closing some roads in Leeds over a weekend, then this scheme would close most of Sheffield Midland for months.
Meadowhall is good enough for me, especially as i means not needing to shut anything down in Sheffield
You are not going to be able to build Leeds New Lane by closing Great Wilson Street / Victoria Road for a weekend. It's just not going to happen. Until you've got a box that the contractors can safely work inside, and the public can travel under, you will have to close one or both of those roads. In the case of Great Wilson Street, completely. My (finger in the air) guess is that this would be somewhere between 1 and 2 months.
Have you ever seen a steel building get erected? Particularly a one-storey portal frame structure? It takes a couple of days. It is quick, I know. What then takes the time is all the rest of it: the cladding, the glazing, the fit out etc. You would need at least the cladding and bracing in place before re-opening those roads.
I would also remind you that these are not some back streets which could be easily closed. These are main routes from the motorway into the city centre and out again. Any closure would have massive repercussions, and affect the public support for HS2.
I agree that using Sheffield Midland would be disruptive in the short term. But using Meadowhall will be disruptive to HS2 passengers for Sheffield CC in the long term. Sheffield is the destination of choice for most HS2 users, not Meadowhall.
Yes there will be disruption at Sheffield Midland. I don't believe that most of it will be closed for months, though. Plus, the work can be staged so that Sheffield Midland remains partly open at least most of the time. In order of ease (easiest to hardest)...
Dore to Sheffield There is already room for 4 tracks between Dore and Sheffield. In fact there probably was 4 tracks at one stage. There would be a short section up to 6 tracks wide where HS2 diverges. Most of the work required for this could be done in weekend/christmas/easter closures. (Although I concede that a blockade a la Nottingham station would probably get it done faster and cheaper.)
If you to do a blockade, then do the northern throat first. This allows the extra services in from the north, and you can run trains through Darnall instead of Dore. Disruption is then limited to passengers from Hope Valley line. Buses could be used between Dore and Sheffield (or a long round trip via Chesterfield).
Shrewsbury Road and Granville Road Bridges Shrewsbury Road Bridge would probably have to go, to allow for longer platforms for HS2 services and an improved Southern throat. This looks to me to be a fairly minor/local route, and the diversionary route is only a mile or two for cars. I'm not sure whether Granville Road would need any change or not. It depends on the distances involved (difficult to tell from Bing maps). This may need an extra span on the west side, in which case a new 3-span bridge to the south, ramping down on the site of the MacDonalds (and business next door) would be less disruptive.
New platforms at Sheffield Midland One possible construction sequence...
1. Find new place (outside Sheffield CC) for depot and stabling trains. (Relatively low cost, no disruption to passengers)
2. Construct new island between 1 and 2 (Done in normal possessions to limit disruption to services. Possibly increase hours available for possession on late nights and very early mornings, say 20:00 to 06:00, by using platforms 3 to 8 only. The reduced service at this time would help in that. This new island would have a through road on the west (2X), and 2 bays on the East (3X and 4X). Note that the line for 3X and 4X is actually the line serving 2, and is currently a through line. It also cuts off access to 2X, 3X and 4X for the moment.
3. Construct temporary access to 2X, 3X and 4X. Some contractors use temporary bridges made of polystyrene blocks to allow plant to pass from one platform to the other. This can be erected in a single night. Almost zero disruption. This does block 2 as a through route, but 2X has compensated.
4. Construct permanent access to 2X, 3X and 4X adjacent to temporary. To include staircase and lift connection to footbridge. Remove temporary when ready. Build new support for footbridge in this location, to allow existing support on island to be removed later.
5. Construct new bay platforms 5X and 6X by cutting into old platform 2, and laying rails.
6. Close 3X and 4X. Use space to make 5X and 6X wider (accessed from 2X side).
7. Do a similar thing on the other side of the platform 2-5 island, including connection to footbridge.
8. Remove old connection from island 2-5 to footbridge. New connections are already in place.
9. Split enlarged island into 2. Make existing bays 3 and 4 into two through lines. Will probably require removal of footbridge supports, but new ones have already been provided on new bays.
You now have 2 extra through-line platforms. Extending the station south (see Shrewsbury Road and Granville Road Bridges above) allows terminating MML trains to occupy a bay instead of a through platform. That gives 7 through platforms to be shared by HS2, Cross Country and Transpennine services. I think that's do-able.
Sheffield Midland North Throat Personally I reckon you could get the line 4-tracked to Nunnery Lane Junction by widening the cutting (although 3 tracks with a single bi-directional line for the Darnall-bound trains would probably be easier). It would take some heavy engineering though, and a long possession of that stretch of line. Land purchase would be minimal as it would be between the existing line and Park Square Roundabout for most of it.
I also think that some of the road bridges over the line are no longer in use (Anson Street and South Street Park form a dead end so closure might be easier). Duke Street, High Street Lane and Bard Street bridge closures could be staggered to maintain road access. Old street Bridge could be closed while maintaining access from the other side. The junction of Cricket Inn Road and Broad Street could be remodelled to avoid it going over the railway. Land purchase would be minimal as it would be between the existing line and Park Square Roundabout for most of it. According to Multimap, there is some sort of car park (or possibly car dealership) over the line at Stepney Street. I would bet that Network Rail own this land and could force a move if they needed to. I'm not sure how much more access is needed to Stepney Street.
Having looked at this section of line with this in mind, I don't think you would need to close any of the Sheffield Supertram to achieve this, as the bridge crosses the throat before it merges into two tracks. This would help keep the cost down.
As far as operations during the blockade goes, London St P - Shef trains could operate as normal, as could Shef-Man. Local services would have to terminate at Meadowhall. (If only there were a tram system that could shuttle passengers between Sheffield Midland and Meadowhall during the disruption). The easiest way of dealing with XC services is to temporarily reopen Rotherham Masborough, stop the XC's there, and run shuttle buses to Shef. XC could then run round Sheffield to Chesterfield.
This leaves you with 2 tracks heading to Meadowhall and 1 or 2 to Darnall. Darnall services are now completely separated from Meadowhall ones, and can be ignored for the purposes of this discussion. You still have a pinch point on the viaduct as far as Brightside. I don't plan on doing anything about the viaduct, as it would be expensive. Instead, I would use points and flyovers between Brightside Lane and the Meadowhall junction to sort out the different flows.
GingerSte on a blank canvas you are correct. In the modern climate it is not workable.
Which bit? If you give me specifics I can answer them.
I would point out that HS2 is the closest thing to a blank canvas that we will get in our lifetime. I think that my scheme for Leeds would possibly save money (although wouldn't stake my reputation on it without a proper costing). The Sheffield Station would be difficult, yes, but £1 billion extra cost (according to someone in Sheffield who did the numbers) for £4 billion in benefit is almost a no-brainer.
