Hacker News new | past | comments | ask | show | jobs | submit login
UK's largest tunnel cutting head lowered into its London shaft (ianvisits.co.uk)
35 points by edward 3 days ago | hide | past | favorite | 66 comments

FYI, the Silvertown tunnel is not with controversy:

> The scheme has faced widespread opposition from local people, politicians, climate scientists and medical experts who say it would increase traffic and worsen public health in some of the most deprived boroughs in the country. They also say it will lock in high carbon transport for generations to come.







The last one is the big one. London is so congested any attempt to relieve the congestion just results in more traffic because of latent demand.

Yeah. If they made it bus/cycle/walking only, that would be much better to actually make it better for people to use public transport. That said, plenty of traffic in London is commercial and a delivery driver can't just use the bus.

Better yet if the old tunnel was turned into pedestrian/cycle.

Then you get proper bus options through the taller tunnel, and proper human-powered options with nobody to run them over, win win.

And I guess we're not replacing lorries/vans for a while yet, so they can use the big tunnel with the busses I guess.

And cars can go via the m25, no need for them in the city. Maybe multi-pasenger/disabled only (incentivises carpooling, helps families who need a cubic meter of junk per baby, and disabled people have genuine needs for their adapted vehicles).

But yeah, the harder cars are to use in cities, the better for everyone (even the drivers often enough, still takes them the same time, but now they're not trapped queuing in a fuming tunnel, instead they're dancing playfully through one-way puzzles... ok, maybe it's not much better for them, but not _much_ worse either).

You free up road infrastructure for commercial use by making it easier for people to switch. It'd probably be a big improvement for commercial use.

Are a few tunnels really going to add a significant amount of pollution to the city of London? “Worsen public health” seems like a bit of a stretch.

In London as a whole, not really. But in the areas adjacent to the tunnel, probably.

Correct, and that's what it says above: "worsen public health in some of the most deprived boroughs in the country" (i.e. in the area of the tunnel).

I wish we could match infrastructure projects like this in the rest of the country.

London is like another planet compared to the rest of the UK.

One thing that's rarely taken into account is that the town planning departments of many other cities are run by absolute mental cases as are the accounting departments. London has, for as long as I can remember, had fairly decent town planners and it generates enough money that over time even excessively expensive solutions end up being largely worthwhile in the end (Millenium Bridge for example).

All other cities of any size need to have town planners that are top quality.

I doubt it’s a coincidence. Chicken and egg isn’t it. Having no interesting well funded projects is unlikely to attract top talent to those planning departments

The lack of investment outside of London is quite deliberate

The UK has a "Minister for London". I don't think many (any?) other country has a ministry for a single city.

That being said, while it's true that many of the "headlines" come from LN projects (Tideway, Elizabeth Line, this) it seems there have been many recent infra projects across the UK. Example: https://www.eclcivils.co.uk/the-uks-major-infrastructure-pro... and https://infrastructure.planninginspectorate.gov.uk/projects/

(Though the latter map is missing any points in Scotland. Whether that is an issue with data quality or with actual infrastructure planning policies is left as an exercise to the reader)

Who is the minister for London? I live in London and have never heard of that title. Do you mean mayor?

Paul Scully, according to Wikipedia.

One factor is that London is so much larger than the next biggest city (approx 9million vs 1.1 million).

It's much harder to justify (and pay for) these kind of infrastructure projects in small cities.

For some reason, for population, we always count the Greater London conurbation as just 'London' when we don't do the same for other cities. This creates the perception that London is an order of magnitude larger, when in fact it's not.

A more accurate comparison is with the total conurbation size of other cities. For example, Manchester is listed as having a population of about 550000, but the Greater Manchester conurbation (the equivalent of Greater London) has a total population of 2.8 million.

Birmingham is 1.1 million, but the contiguous West Midlands conurbation is about 2.9 million.

The Liverpool to Leeds cross-Pennine urban axis (which is nearly contiguous) has a population of nearly 7 million.

Yes, these are smaller than Greater London, but not by the amount you think.

I think this is what "Northern Powerhouse Rail" was supposed to address, but I don't know if it's going to get as much love as a London project, if it goes ahead at all :(

For any non-UK people who aren't familiar, here's here's a simple map showing pop. density to give you a rough idea what we're dealing with: https://www.researchgate.net/figure/Gridded-UK-population-de...

You can clearly see the areas in question - London being the big red/purple blob in the far south-east, and the cities/conurbations marmarama described are to the north and north-west of that. They're not individually on the scale of London, but they're substantial population centres that would see real benefits from this kind of public transport infrastructure investment.

Not just harder to justify but the length of time (approx 10 years?) that it can take between the initial investment and people adjusting their lifestyle/moving to take advantage of the new infrastructure.

That said, Manchester, Leeds, Bristol and Birmingham (I'm sure others that I don't know about) have all done an enormous amount of work in the last 10-20 years to modernise.

Transport is hardest of all, of course, since you don't have the space usually to create greener systems without removing something else like a road and not everyone can simply swap easily. That said, I wish they would take some bold decisions across the UK and, like the Hague, make whole town centres pedestrianised during the day to try and force it a bit.

That results in a self-fulfilling prophecy though, doesn't it.

Absolutely. Germany, by contrast, has several cities that you regard as of on a par.

Yes. Frankly, the continued over centralisation of the country around London seems to me to be the single greatest threat to the future prosperity of the country

When you factor in climate change and rising sea levels, London is going to become unsustainable in the next 100-200 years. The Thames Barrier already needs replacing with a bigger structure, or it will become too small to cope sometime in the late 21st century. Possibly sooner than that if warming trends continue to accelerate.

While I appreciate that investment in London needs to happen to solve issues now, the UK should be pivoting more investment to its regional cities that are in more sustainable locations, so that the UK is prepared for when London eventually succumbs to the tides.

London will be underwater and you still won't be able to afford a Victorian terrace.

I've honestly always thought of anything within the M25 as the fifth country of the United Kingdom.

~60m people in Britain. About 20m of then live within 1 hour of the centre of London.

I'm not sure I follow your point. I live about an hour from the "centre" of London.

That doesn't mean I want to travel 2 hours a day just to use London's infrastructure.

London is a big place. The centre of London is big. Where my train comes into London is not necessarily where what I need to do is.

So there could be another further hour of travel each way to get across London.

Travelling to and from the station on the home end is also a problem. Since public transport is so dire outside of London that takes much longer than it should do and is much more inconvenient.

Where friends of mine get annoyed waiting 5 minutes for a bus in London, you could be waiting over an hour in the rest of the country ...and if you miss it you're in schtuck, because it's the only one that day.

How much daily travel should we have to put up?

Just to be clear, I don't want less in London, I want more/better outside of London.

Yes, but it would be about 10m if London had the same underperforming transport infrastructure as the rest of the country.

That seems to be a common attitude in the UK and it’s not helpful. We should be building London level or better transport in the rest of the country, not wrecking Londons transport to bring it into line.

I was not talking about wrecking London's transport, merely using a thought experiment to illustrate how much better London's transport is than what the rest of the country has to put up with.


I understand your vibe though.

HS2 is completely unnecessary though. Manchester to London is currently 2 hours. Unless it was going to halve that time, which it won't.

The point in hs2 isn’t mainly to reduce journey time, even though that is what is usually touted in news articles. It’s to increase capacity and reduce the contention between high speed intercity services and commuter services with many stops. The west coast main line is extremely busy and if you’re going to build more track you might as well build it for modern train speeds.

> Unless it was going to halve that time, which it won't.

Why are people so mistaken about HS2. It doesn't halve the time, but IT INCREASES CAPACITY!

The West Coast Mainline is congested, and so twisty it's like a rollercoaster in places.

I'm really confused, because everyone connected with rail seems to be completely 100% aligned on this and they'll repeatedly explain in very easy-to-digest terms the existing problems, and how HS2 will alleviate many of them. It seems like such a no-brainer.

... and yet so much of the public (and ... [sigh] the news and various politicians) seem to be laser-focussed on travel time, and loudly question whether a quicker north/south line is really worth it. And they'll often talk about the focus should instead be on improving utilisation of the existing without knowing that these main north/south lines are already very near capacity.

If I was a rail guy in the UK I'd probably lose my mind.

The HS in HS2 stands for "High Speed", so people expect it to be, you know, higher speed than what we have today.

It is higher speed. It's just not the speed you think it is. And higher peak speed doesn't linearly translate to lower journey time, as you need to speed up and slow down at either end!

People aren't stupid, they can understand that a project can deliver more benefits than just the words in a project's name.

But you've got knowledgeable people patiently giving plain easy-to-digest descriptions on the benefits ... which are ignored entirely by those with a bigger platforms who boil it down to "do we really need the fast trains?"

It's because travel time is the number 1 decided factor on where you live when you are commuting.

were you not there when the politicians were selling it?

it was supposed to somehow help the north by cutting journey times.

Wasn't that about the northern parts that they aren't working on right now? The lower parts that are going ahead with now were about capacity.

"The government says that HS2 will free up capacity by taking the long distance trains off existing lines and on to the new high speed line."

That's what they were talking about in 2013 https://www.bbc.co.uk/news/magazine-24159571.

I seem to recall them talking about it as a whole? Maybe I just received the northern targeted sales pitch.

That's one very impressive machine.

For perspective, it's 3.6 meters larger in diameter than the channel tunnel bore diameter.

yeah, it would be great if the UK wasn't so London centric.

the contrast between london and other places in the uk is dire

No one mentioned Seattle's own huge tunnel machine that infamously broke down partway into the job. It was a little larger, at 17.5 meters vs 11.91 meters for this latest UK tunnel machine. It broke down about 1000 feet into the 10k long tunnel. Among the many reasons why the US can't build infrastructure like this is we had specific public votes and lots of grousing along the way. I was proud we managed to pull it off and recover from that major failure. https://en.m.wikipedia.org/wiki/Bertha_(tunnel_boring_machin...

You also have the Central Subway. Which seems to be taking a long time, should open in September years behind schedule.

However the tunnel boring part didn't seem to be an issue.


Instead of creating more opportunities for car drivers I would prefer a cycle tunnel.

I think some of the drivers who are currently using the Blackwall tunnel would switch to cycling if this was available.

Currently getting across the river in that area on bicycle is very difficult. You would have to ride to the greenwich foot tunnel and walk.

To me that would be a cheaper and quicker win.

> "Currently getting across the river in that area on bicycle is very difficult. You would have to ride to the greenwich foot tunnel and walk."

I jokingly call it the "Greenwich cycle tunnel" because there's always a large number of people cycling through it despite the many signs saying it's forbidden!

IMO a cycle/pedestrian crossing between the Canada Water/Surry Docks area and Canary Wharf (replacing the existing expensive ferry) would be a game changer that would lead to greatly increased development on the south side. But unlikely to happen because it's hard to put a toll on a cycle/pedestrian crossing to pay for it!

> because it's hard to put a toll on a cycle/pedestrian crossing

In a political sense maybe, but in a technical sense that's just what is already done with subway turnstiles.

Since they're building it right next to an existing tunnel, and the main reason given is for double decker busses, it seems like it would be fairly easy to make it zero emissions vehicles only and add a bike lane too.

Existing, non-zero emissions vehicles can use the old tunnel and be phased out over time, lane by lane.

edit: but on reading more, it seems mostly to be about charging HGV tolls.

If they're having to build a tunnel specifically to accommodate double decker busses that are "just a bit too tall", it sounds like whoever procured the "Boris busses" didn't do their homework, so now we're spending millions to fix something that could have been solved at no cost by buying slightly smaller busses?

I mean, on paper you'd have to walk the tunnel.

In practice, everyone rides their bike, scooter or whatever in the tunnel. And honestly I find it really hard to blame them: sure it's "forbidden", but I'd do the same if I was them (as long as you are not just speeding like a madman)

Why do they have to walk? Is this a london thing? Or is it just this one tunnel?

Answering my own question, it's quite a small, two way traffic tunnel.


Rule of the specific tunnel. Its not particularly spacious...

That's false, Blackwall tunnel is completely banned for non-motor traffic. The pedestrian path way is for emergency use only and it's blocked off at both ends. Going down there with a bike is suicidal and also prohibited. During my 7 years commute on the A2 I have never seen a single bicycle down the tunnel.

You sure you're not mistaken for Rotherhithe tunnel?

edit: I see you're referring to Greenwich tunnel. Fair points.

I am referring to the Greenwich tunnel. Rotherhithe tunnel does allow bikes but it's pretty scarey, you're right next to the cars.

I've always liked the idea of turning the northbound blackwall tunnel into a combined underground shopping centre/cycle lane/footpath. It's ill-suited to motor vehicles in any case and could be replaced with a new northbound vehicle tunnel.

Idea would be to split the tunnel into two levels with a deck, have the lower right hand lane for cyclists (two way), upper right hand side for pedestrians and the entire left side for shops with frequent stairs/lifts for access between the two levels.

London had this years ago in the form of the Thames Tunnel, however the gloomy gas lighting meant it didn't last long as a pedestrian tunnel. With modern lighting and ventilation I wonder if this is a possiblity.

Bikers are light. A bike and pedestrian tall bridge makes more sense. And it can double as tourist attraction. See London's Millenium Bridge.

A bridge across the Thames needs to be very tall to allow ships to pass underneath. Or have the ability to open up for ship traffic like Tower Bridge. This is why tunnels are likely to be cheaper/easier.

This is an excellent idea TBH

This tunnel is long overdue.

People living in East London and South London find it really inconvenient to travel between the both since the birth of London. The Thames River is very wide in the East unlike West London.

It can take between 40 minutes to 1h20m to drive the 500 meter distance between East London and South, by travelling through tunnels or bridges closer to Central London.

How many double decker buses are there per Library of Congress?

anyone know if it cheaper to make a bridge or tunnel across the thames?

For the actual bridge vs the actual tunnel, tunnels start to outcompete once you get a length over a mile or so, so I'd guess bridge.

But since this is in the middle of a busy city, I'd guess other factors dominate, costs for land access and approach roads, river traffic, appearances etc.

The elevation needed for boats to cross under can make the bridge initial cost really high, depending on the height you need to accommodate.

Honestly, i would just trust the architects and urban planners. At least in my country, every new development i saw recently, even those i was kind of against at first (in 4 different cities) were upgrades once finished. Even when it lost something i really was attached to, i have to admit that this is overall better now.

The river at Silvertown is atleast 500m wide.

Tall and short ships and boats travel up and down it.

A bridge would cost a lot to upkeep.

It shouldn't matter. Move all cars underground, bridges are ugly (when up close / under), noisy and crime ridden.

Guidelines | FAQ | Lists | API | Security | Legal | Apply to YC | Contact