Fantasy: Major Infrastructure with Zero Chance of being Built

[zwk500]

Any bridge/tunnel ideas between Ireland and the UK

The Scotland-NI ideas are IMHO way too incovenient for access to the rest of the UK

A direct Holyhead-Dublin would be great but hard and expensive AF to build.

The most appealing, but the most expensive proposal, in my opinion is the Liverpool-Isle of Man-Ireland, serving 2 communities with better infrastructure in one go.

The only route that makes any sense is Holyhead-Dublin, IMO.

 

[CMS1]

An the other hand, Belfast is more direct via Cairnryan for most of the UK cities, and same length from london as going via Dublin. What are the flow to NI vs IE? And it joins the UK up without involving another country. Obviously the biggest benefit being approx 22miles rather than 62

 

[zwk500]

An the other hand, Belfast is more direct via Cairnryan for most of the UK cities, and same length from london as going via Dublin. What are the flow to NI vs IE? And it joins the UK up without involving another country. Obviously the biggest benefit being approx 22miles rather than 62

Dublin is the market you're after with an Irish Sea Tunnel. Greater Dublin area has a population of c.2m vs 0.75m for Belfast Metropolitan area. GDP of just under €250bn vs just under £36bn.

Economy of Dublin - Wikipedia

en.wikipedia.org

Belfast Region Investment Guide 2025 - At a glance

The Belfast region presents an exceptional opportunity for investment, with unmatched potential on the international stage.

www.belfastcity.gov.uk

Any Irish Sea Tunnel wants to connect Belfast to London and Dublin to the wider UK. Holyhead is the obvious route. As shown by the numbers on the relevant Ferry and Air routes.

 

[deltic]

Every conurbation in the UK with a population over 250,000 to have a fully automated 24hr metro network which would relieve pressure on city centre terminals allowing a large increase in inter-urban and inter city services. Copenhagen shows what can be done.

 

[Bald Rick]

Energy related you could have some huge pumped storage/hydro schemes in scotland

That’s not speculative, they are coming…

 

[Magdalia]

Every conurbation in the UK with a population over 250,000 to have a fully automated 24hr metro network which would relieve pressure on city centre terminals allowing a large increase in inter-urban and inter city services. Copenhagen shows what can be done.

This is the major transport infrastructure that would benefit most people and make the biggest contribution to the economy.

Here in the Fens light rail for Cambridge is very popular amongst local politicians and the people who follow local politics, and I'm not very popular when I tell any of them that there is zero chance of it being built.

== Doublepost prevention - post automatically merged: 1 Aug 2025 ==

Energy related you could have some huge pumped storage/hydro schemes in scotland, or the Severn barrage

You have forgotten water. We need reservoirs. Hopefully some will get built, such as the Fen reservoir at Chatteris.

 

[Topological]

A lower level Birmingham New Street taking the cross city and Walsall/Wolverhampton stopper lines

Related: Heard and could have been a rumour, there was a one off opportunity for another tunnel by proof house while the Bull Ring was redeveloped but was not taken.

A lower tunnel for the Cross City would be a very good addition to Birmingham. With a little more vision the route could go through the University itself and stay off the main line until Kings Norton. That would then free up a lot of paths for services from Bristol/Cardiff without impacting capacity through Camp Hill. A Y shape to connect to Tamworth/Lichfield as well as the Wolverhampton/Walsall via Bescott route would be transformational.

The only thing missing then would be a few smaller works on the Coventry line to allow more local services amongst the semi-fasts still heading to London via Rugby.

 

[Schweir]

A new station at Southampton C, and a new tunnel under the Itchen to lower journey times along the West Coastway

 

[Austriantrain]

Every conurbation in the UK with a population over 250,000 to have a fully automated 24hr metro network which would relieve pressure on city centre terminals allowing a large increase in inter-urban and inter city services. Copenhagen shows what can be done.

Copenhagen is slightly larger than 250.000 people…

When such schemes are evaluated on the Continent for smallish cities, they invariable lose out to ground Transport. It is not only digging the Tunnels and - especially - building the stations that is very expensive, the cost of operating them is exorbitant, as several not-so-small German cities had to find out.

 

[Uncle Buck]

Every conurbation in the UK with a population over 250,000 to have a fully automated 24hr metro network which would relieve pressure on city centre terminals allowing a large increase in inter-urban and inter city services. Copenhagen shows what can be done.

Copenhagen is slightly larger than 250.000 people…

When such schemes are evaluated on the Continent for smallish cities, they invariable lose out to ground Transport. It is not only digging the Tunnels and - especially - building the stations that is very expensive, the cost of operating them is exorbitant, as several not-so-small German cities had to find out.

How about we aim to have one in Belfast, Cardiff, Glasgow, Edinburgh, Liverpool, Manchester, Birmingham/Wolverhampton, Bristol/Bath, Southampton/Portsmouth, Newcastle/Sunderland, Leeds/Bradford, Sheffield, Nottingham/Derby then, with the existing systems that cover these areas being expanded as appropriate? Every sizeable town had a tram network before World War I after all!

 

[OhNoAPacer]

I haven't seen it being talked about recently but there have periodically been campaigns for a road bridge across Morecambe Bay from the Furness peninsula.

 

[Tomos y Tanc]

I haven't seen it being talked about recently but there have periodically been campaigns for a road bridge across Morecambe Bay from the Furness peninsula.

Handy for Barrow v Morecambe derby matches. Oh wait...

 

[zwk500]

I haven't seen it being talked about recently but there have periodically been campaigns for a road bridge across Morecambe Bay from the Furness peninsula.

That would probably set the record for longest Environmental Impact Statement so far

 

[greyman42]

Four tracking of Digswell Viaduct?

 

[brad465]

A new station at Southampton C, and a new tunnel under the Itchen to lower journey times along the West Coastway

On a similar theme, a tunnel under the Solent to directly link to the Isle of Wight, probably from somewhere near Portsmouth to the island, maybe to Newport via Cowes or via Ryde. Not going to happen on the basis that it would either have a poor business case, and/or have an extreme backlash from locals fearing an overwhelming tourism surge.

 

[wanderingriver]

Any bridge/tunnel ideas between Ireland and the UK

The Scotland-NI ideas are IMHO way too incovenient for access to the rest of the UK

A direct Holyhead-Dublin would be great but hard and expensive AF to build.

The most appealing, but the most expensive proposal, in my opinion is the Liverpool-Isle of Man-Ireland, serving 2 communities with better infrastructure in one go.

Isle of Wight could use a tunnel as well

 

[zwk500]

On a similar theme, a tunnel under the Solent to directly link to the Isle of Wight, probably from somewhere near Portsmouth to the island, maybe to Newport via Cowes or via Ryde. Not going to happen on the basis that it would either have a poor business case, and/or have an extreme backlash from locals fearing an overwhelming tourism surge.

Isle of Wight could use a tunnel as well

The pure crayon idea would be to cut off Portsmouth Harbour and drop the line into a tunnel somewhere along the viaduct, pop under the channel to Gosport then on to Ryde. As you say, never a chance of happening.

 

[HSTEd]

I could see a gondola lift onto the island, especially if it replaces the Lymington Branch and was thus somewhat less likely to result in overwhelming tourist numbers.

 

[Palmerston]

If it's just a rail tunnel to the IoW with no additional car traffic likely, that seems like less people would object.

 

[InTheEastMids]

Has anybody mentioned Midland Mainline Electrification yet?

 

[AndrewE]

I could see a gondola lift onto the island, especially if it replaces the Lymington Branch and was thus somewhat less likely to result in overwhelming tourist numbers.

That really does sound like a Minimum Viable Product (as in https://www.railforums.co.uk/thread...ven-railway-tunnel.257724/page-3#post-7404363): see how busy it is and if it is overwhelmed, then just run a rail shuttle and some boats to increase capacity!

If it's just a rail tunnel to the IoW with no additional car traffic likely, that seems like less people would object.

The tunnel would be the logical next step after the boats mentioned above being unable to cope with the demand...

 

[Magdalia]

Here in the Fens light rail for Cambridge is very popular amongst local politicians and the people who follow local politics, and I'm not very popular when I tell any of them that there is zero chance of it being built.

digging the Tunnels and - especially - building the stations that is very expensive

This is my explanation of why there is zero chance of light rail happening in Cambridge.

Not only are tunnels and stations very expensive but constructing them is very disruptive too.

A big city like London can cope with the disruption, for example around the Elizabeth Line stations, but that level of disruption in a small city would be very destructive for the local economy.

 

[Falcon1200]

Youd need a new line all the way to Paddington for that…

Start off by 6-tracking the GWML out to Reading, giving TfL would dedicated lines for their services......

 

[Mikey C]

If we're getting crayons out, and thinking about the two ends of the growth corridor for which EWR is bring built for.

A new or heavily upgraded line between Cambridge and Norwich, to speed up connections between them AND make this the main route to Norwich. While culturally and football wise Norwich and Ipswich might be paired, in terms of the high tech future, the corridor is between Cambridge and Norwich.

At the other end, a light rail network based at Oxford, going to Witney in the west, Wheatley in the east, and south to Abingdon, Didcot and the Harwell campus.

 

[fishwomp]

I propose a high-speed line from Manchester (or even beyond Bolton/Preston or Liverpool) to Sheffield and onto Nottingham or Derby via Chesterfield. Could help relieve Hope valley pressure and conventional lines to the south of Sheffield. Would never happen and would probably need a station upgrade in Sheffield to go along with it, but we can only dream.

Ideally, it would start in Piccadilly, pass by a large freight yard in Mottram, and a few miles later enter a 3-mile purpose built modern tunnel, coming out somewhere like Dunford Bridge, from there, end up on the newly disused branch from Deepcar to Nunnery Main Line Jct., stopping in a station in Sheffield above the river Sheaf. The new Sheffield station could be a 15 minute walk from the Midland, and linked by tram to it. Then use the existing "old road" (optional diversion via Chesterfield or a new line from Staveley), pop up in a station in Nottingham (can call it Victoria, named after local actor Vicky McClure).

 

[CMS1]

Build a line from Beccles to Norwich, have hourly East Suffolk line services to Norwich, and send the Lowestoft to Norwich service via this new line, closing the wherry line to Lowestoft (which is an awful ride and services nothing useful in between).

 

[Austriantrain]

How about we aim to have one in Belfast, Cardiff, Glasgow, Edinburgh, Liverpool, Manchester, Birmingham/Wolverhampton, Bristol/Bath, Southampton/Portsmouth, Newcastle/Sunderland, Leeds/Bradford, Sheffield, Nottingham/Derby then, with the existing systems that cover these areas being expanded as appropriate? Every sizeable town had a tram network before World War I after all!

Oh, certainly all perfectly suited for tram/light rail. A real metro - Glasgwo obviously. Manchester and Birmingham too, but underground urban rail and/or light rail sections much more useful. Other than that? Even of the UK had the budget surplus of Ireland, in most cases it would not be value for money (and Newcastle obviously has one already)

 

[fishwomp]

In the astronomically unlikely event a Holyhead to Dublin tunnel was every built, the gauge changer is so minor an obstacle as to be barely worth mentioning, it's proven technology.

If it was to happen I think the most likely layout would be a short standard gauge line from the Irish portal to the main Dublin station (probably either new platforms at Connolly or a totally new station), with a gauge changer there for any services beyond Dublin. The majority of the services through the tunnel would likely terminate in Dublin anyway so a little silly to mess around with changing gauge for that sake of 10 miles or so.

Well.. there's always the Luas trams - standard gauge - either the mostly straight red line from Dublin docks to the west, or the bit-too-bendy green line north-south.

 

[gingertom]

Get rid of the Newark flat crossing.
Welwyn viaduct and tunnel 4 tracking.

 

[Magdalia]

Four tracking of Digswell Viaduct?

Welwyn viaduct and tunnel 4 tracking.

Splendid to see people recognising that there is zero chance of this!