During various on-off crayoning episodes involving the Wapping tunnel, I came across the report attached above, and whilst agree with certain aspects, other things I would take a longer look at. There are problems with the width narrowness of 22ft (6,706mm), the inclination steepness of 1 in 48 (2.08%) and the extreme proximity of historically significant structures at the eastern end, some of which are concealed underground. Even my own crude efforts have put the connecting tunnels from the existing headings at Central to a point by Blackburne Place have shown the gradient could be very steep, maybe 1 in 40 (2.5%). While using the tunnel could form part of a long-term solution Liverpool's transport problems, I would vouchsafe the following comments:
1: Nobody is going to be digging holes under Liverpool without sufficient cause to do so.
2: If you are going to dig holes, they must be of sufficient size and quality as to long-term usage, maintenance and upgradeablity.
But all is not lost.
So 'Yes' to:
Resignalling of the Inner Loop and Link Lines to allow closer headways, in the manner of the London Underground.
Expansion of Central Station to three or maybe even four platforms.
Proposed Station (Northern Line) to the north of Chadwick Street called Liverpool Waters or Vauxhall. This is to break up the long section south of Sandhills and serve an up-coming residential area.
Proposed Station (City Line) south of Wellington Road called Wavertree.
Proposed Station (City Line) south of Smithdown Road called Smithdown Road.
Proposed Station (City Line) east of Woodend Avenue called Speke for John Lennon Airport. To serve as a terminus pending possible extension to South Widnes etc. A bus shuttle to the airport.
Splitting of the lines in Birkenhead: West Kirby and New Brighton services retaining the name Wirral Line, the services south to Chester and Ellesmere Port taking the name 'Sunlight Line', from Port Sunlight.
The extension of the Borderlands Line through the Liverpool loop (rush hours).
The conversion of the following lines to OLE: Northern Line Sandhills and all lines to the north, Northern Line St Michaels and all lines to the south. Wirral Line Birkenhead North and all lines including the Borderlands Line, Wirral Line (Sunlight Line) Rock Ferry and all lines to the south. This will leave a third rail core, which, should battery power develop to such a stage, could be removed entirely.
Track and infrastructure alterations to be made to enhance reliability and remove conflicting moves.
Bus route review and reform.
Also 'Hmm, Maybe' to:
Edge Hill Station Expansion
Proposed line from Hunts Cross, Broad Green, Aintree.
Proposed line from Bootle to Aintree (North Mersey Line).
Proposed service over existing line from Edge Hill to Kirkdale and/or Bootle.
Expansion of Lime Street Station including an extra tunnel from Edge Hill.
Trams.
An 'Ah, Perhaps?' to
Wapping Tunnel (No intermediate stations)
Victoria - Waterloo Tunnel with stations at Paddington/Grove Street and Byrom Street.
And a finally 'What are you on?' to
Any intermediate station on the Wapping Tunnel. (i in 48)
Revival of the Overhead Railway (I've seen too may videos of this). It's been replaced by the Northern Line. Live with it.
Random underground lines.
Excessive Curvature.
Excessive Gradients. (Liverpool is hilly)
Plus any other bonkers schemes.