So let me get this straight. Are these tunnels designed to find an alternative destination for the cross rail trains that are due to terminate at Paddington? And will that in tern help reduce the number of passengers using Euston so that the station won't be overwhelmed once HS2 arrives?
Then plan I came up with does the following:
Services on crossrail currently looking at terminating at Paddington or Old Oak Common will be extended to run onto the West Coast Mainline.
These services will take the form of two Tring terminators and two new services to Watford Junction per hour, also taking the DC line services over from the line North of Wembley Central.
Services affected:
xx:04 Euston to Tring:
Service will be diverted in and out of London Euston to run via Crossrail and into Paddinton, south of Watford Junction would call at Bushey, Harrow and Weldstone, Wembley Central, Old Oak Common Compex, Onwards through Crossrail.
xx:13 Euston to Birmingham New Street via Northampton:
Service will remain as is, potentially inseting a stop at Watford Junction but this will not affect my XR proposal.
xx:24 Euston to Milton Keynes Central:
Service remains unaffected, will be running behind a service (equivilant of xx:19 off Euston ex. Crossrail that will call at the usual stations, and terminate at Watford Junction)
xx:34 Euston to Tring:
Service will be diverted in and out of London Euston to run via Crossrail and into Paddinton, south of Watford Junction would call at Bushey, Harrow and Weldstone, Wembley Central, Old Oak Common Compex, Onwards through Crossrail.
xx:46 Euston to Crewe and Birmingham New Street:
Remains unaffected by this proposal, would potentially be re-timed to xx:43 to prevent clashing with the assitional service running at the xx:49 to Watford Junction terminator.
xx:54 Euston to Northampton:
Service will be unaffected by these service changes, as will all services running beyond Tring.
Services remaining to run from Euston:
xx:13 to Birmingham New Street
xx:24 to Milton Keynes Central
xx:46 to Birmingham New Street and Crewe
xx:54 to Northampton
To run in the oppersite 15min gaps to the current Tring terminators, either two addtional Tring services would run (and result in the removal of stops from LM services, all would now only call at Watford Junction, Tring, Cheddington, Leighton Buzzard, Bletchley (etc.)) or these additional services terminate at Watford Junction with stops remaining on LM services that run North of Tring.
This would releive Euston to 2tph from the AC slows, doesn't sound like much but does present a significant amount of passengers, if the Crossrail services are to be run as I see them happening, then going any further out that Tring with the specified design would not be appropriate.
What I'd come up with for the DC lines is slightly more complex, and would require more services to move around, but would speed up journies from stations north of Wembley on the DC lines.
4tph would run from Crossrail onto the DC lines, these would join and leave the DC line service pattern at Wembley Central, having joined the line by extention of the F Sidings with an additional bridge over the North Circular, with a reversing siding being provided North of Wembley Central on the AC Slows and DC Lines, the former for crossrail services not running North of Wembley (Rather than terminating at Paddington, or during events at Wembley) and on the DC lines for the terminating of some Bakerloo services.
Rather than explaining the change in more detail, I'll just summarise the DC line service pattern after I have made (my proposed) changes as a result of Crossrail Intergration.
4tph Crossrail: Paddington - Old Oak Common - (Join the current DC Lines via the extended F sidings) - Wembley Central - All Stations - Watford Junction.
Some tph: Willesden or Queens Park to Euston or Camden Road via Primrose Hill, the latter would see services continuing to Stratford or East London Line destinations.
Bakerloo Line: Additional services (with the implementation of NGDL Tube Stock) will continue to Harrow & Weldstone and/or Wembley Central to connect with the improved Crossrail services, and help maintain local services lost by the crossrail diversion of DC line services, the only loosers would be those travelling from stations North of H&W to stations South of Wembley Central, catered for by changing at Wembley.
All in all, it removes some services from Euston, if all services extend to Tring, there is the potential to drop the longer distance to all 12 car operation with more splitting at Milton Keynes Central, Northampton or Rugby. Such as a core of 2tph to Birmingham New Street with a standardised calling pattern south of Milton Keynes, North of Milton Keynes services will split for their alternate destinations, intermediate stops could be picked up by new local services, or a service split.