This is not the primary reason behind building HS2. It was a (very silly) political decision to make the narrative all about the journey time. The benefits of HS2 are in taking the fast trains off the existing 4-track WCML between Euston and Rugby.
Very Much this.
Yes, improvements could have been made to every line coming out of every London terminus. But it costs a lot more to work alongside a live railway and can involve significant disruption whilst you do it.
Widening a 2-track railway to a 4-track railway is no easy task. Bridges (over or under) need to be rebuilt. If you're 4-tracking through stations then the stations will often need to be rebuilt. Where the route passes through towns and cities, you'll likely need compulsory purchase and demolition of some buildings to make space for it. The cost and disruption of doing extensive works on an extant line is immense. Just look at the WCML upgrade of the 2000s, or the current Transpennine upgrade – and that one is, as far as I can tell, doesn't actually need any new land because it is using land that was railway land anyway – years of hobbled running, blockades, road replacements, diversions, reduced capacity, delays – building HS2 as a brand new line was orders of magnitude cheaper and quicker plan to deliver than any attempt to get the extra capacity for local and long-distance services out of the existing ECML, MML, XCML and WCML.
Trivialising the benefits of HS2 like that is pathetic and a gross distortion of what the railway was going to deliver before Sunak suknackered it.
DB did a lot of that though didn'tthey ?
You wouldn't, you would tunnel under it.
Yes - Shap Base Tunnel has a certain ring to it!
The WCML south of Birmingham is though unique in being the first 'intercity' railway - even routes engineered 10 years later had a better understanding of the evolution of motive power. The engines of the 1830s struggled with hills but due to their lower speeds didn't have so many issues with curves, so exactly the opposite of modern high speed lines.
The downside to that approach being that it wouldn't release any capacity at all.
Aside from the time savings being more like 40 minutes, it was never about the speed of getting to London. It was about relieving capacity on three major trunk routes out of London when it was first thought up, all of which are already four track railways for much of their length. HS2 would've been the extra two tracks for all three railways with enough of a speed advantage to also help reduce road and air traffic at the same time.
As mentioned above, the European approach would not release any capacity. The better comparison would be the Tokyo-Osaka line which was at capacity even as it was electrified and so was instead relieved by an entirely new route that we now know as the Tokaido Shinkansen which runs like a long-distance Elizabeth Line as much as it does a high-speed intercity passenger railway. HS2 would've been much the same in it's original form.
I don't know enough about continental HSR to know if (a) unlocking capacity on overcrowded mainlines was as significant a feature of the plans as it is in the UK, and (2) if the approaches to Paris and other major destinations were as constrained as they are into Euston, Piccadilly, New Street and Leeds ... but building a new HSR only north from Watford and then sharing tracks into Euston would not have worked because the key point is that Euston and the WCML is already at capacity, and there would be no space for new trains. The best you could achieve in that case would be to replace existing AWC trains with HS2 trains, but that would entirely defeat the point of it.
Not so with TRU.
It's only 4-track for a relatively short distance until the DC Lines split off the Slow Lines. And much of the DC Line service can go down the Bakerloo Line at Queen's Park. It's a much better set-up than, say, the Great Western Main Line, where having only 4 tracks between Old Oak Common and Maidenhead really is far from ideal (and with the advent of the Lizzy Line, the old solution of running a deliberately bad local service to deter patronage no longer works).
I think this is at least part of the problem. Local authorities can block or frustrate major infrastructure builds that are required as part of a 'national asset'. This blocking can be for totally political reasons. Personally I would say that once a scheme has been approved by Parliment (i.e. something like HS2), or an improvement is required for something like electrification then local authorities capacity to block and frustrate should be severely limited. I would couple this with generous (above market value) compensation for those directly affected, i.e. those whose land is purchased or environment is affected directly. These sort of projects should not fall into the normal planning rules once a detailed proposal has been approved by Parliment.
I stand corrected
