Forum Topic

How Viable is the Hammersmith 'Flyunder'?

First off well done to the local architects for putting together plans for this scheme. If it was to come off it would have the potential to transform this part of West London.The first question is who owns the land under and around the current flyover? If it is TfL then the maths would stack up but if not the cost of land acquisition would make the scheme unviable.Also what gets built on the land above the tunnel? If the availability of this prime land only leads to a new 'Golden Mile' of office blocks we will have only replaced on mass of concrete and steel for another.Would the tunnel be a toll? I'm sure TfL would argue for this but to do so would mean more traffic on local streets as people seek to avoid paying so we would end up with more cars on our streets not fewer.

Paul Corcoran ● 4361d62 Comments

'isn't the issue that new diesel cars *don't* have appreciably better "real world" performance than older cars?'I thought the problem was that the tests are, and always have been based on laboratory conditions for the simple reason they need to be standardised. It has always been the case that emissions are higher in real world conditions but which ever measure you use they are coming down. This is why globally air pollution is falling in most major cities.'The report below showed only a 0.3% difference in NOx emissions from a Euro VI engine between a 20mph drive cycle and a 30mph drive cycle when driving around real routes in London. 'Surely not a surprise - the problem is the amount of driving done in first and second gear below 10mph when emissions are highest.'The headline figure was about 35% of trips by mechanised modes were potentially cyclable'If you exclude from that the number of journeys that are potentially walkable and a make a reasonable qualitative assessment of the percentage of other journeys that will never be switched for a variety of 'soft' reasons e.g. safety concerns or even just entrenched laziness you are still going to find it hard to get a meaningful substitution level even in the most positive of environments.The Department of Transport release a list of roads in the country which are seeing the lowest travel speeds - they are all in London. This is not due to population growth because the number of vehicles on London's roads is falling. It is due to the reduction in road capacity mainly by the increase in amount of space given to buses and to a lesser extent cycles. I am not arguing that to do this was necessarily a bad thing just to think that doing more of the same will somehow no longer cause congestion but will now have the reverse effect.

Paul Corcoran ● 3353d

"a new diesel car will have a lower level of NOx emission than an old diesel car."However isn't the issue that new diesel cars *don't* have appreciably better "real world" performance than older cars?Also, in the figures I quoted from the GLA report, I only mentioned diesel sources.Petrol cars are responsible for an additional 7% of London NOx emissions."in narrow roads which are the ones most likely to experience congestion a cyclist takes up just as much space as a car"https://farm9.staticflickr.com/8318/8009097414_d9d6c1cbcc_z.jpgIn this photo taken on Theobalds Rd, there are about 26 or so people on bikes stopped at the lights.  At average London car occupancy rates, the same number of people would be carried in about 20 cars. So with 10 cars in each lane, the queue would go back 60m or so.  The drivers at the back of a queue of 10 cars aren't being held back by the bikes, they would be held back by the cars in front of them!"It isn’t disputed by anyone else that emissions are higher when traffic speeds are lower"But what is the difference in reality?  The report below showed only a 0.3% difference in NOx emissions from a Euro VI engine between a 20mph drive cycle and a 30mph drive cycle when driving around real routes in London.  https://www.cityoflondon.gov.uk/business/environmental-health/environmental-protection/air-quality/Documents/speed-restriction-air-quality-report-2013-for-web.pdfReduced emissions at higher cruising speeds are offset by increased acceleration and deceleration resulting from the inherent stop/go nature of driving in London.There isn't any argument that higher cruising speeds mean less emissions but given that 67% of car trips in London are under 3 miles, there is no way that the average speed of trips this short will come anywhere near to the optimum cruising speed for emissions (what is this..about 50-60 mph?)Reducing pollution by trying to smooth traffic slow is doomed to failure in London as it is impossible to make this number of short trips fast, direct and continuous."However, the vast majority of journeys that are undertaken in the capital could not be substituted with a bike ride."There has been a lot of analysis on this (TfL aren't building cycle routes just for the fun of it...)http://content.tfl.gov.uk/analysis-of-cycling-potential.pdfThe headline figure was about 35% of trips by mechanised modes were potentially cyclable and the report has more analysis of this.  I could quibble with the criteria they used to determine if a trip was cyclable or not (they assumed people over 64 wouldn't ride a bike..) but the figures are what they are...  A "majority" but certainly not "vast majority"."Private car journeys have been falling in London for some time, probably due to the increased cost of motoring but in recent years this trend seems to have stopped."The latest figures show that private car journeys in the central London boroughs have continued to fall.  Figures for outer London have shown an uptick in the last year but it remains to be seen if it is a trend.There are a lot more factors than cost behind these trends.  Congestion charging, reallocation of road space to bus lanes and controlled parking zones affect driving as well.  Also there is no point driving if there is nowhere to park. Developers can make more per square foot from retail, residential and business than car parking so new developments and redevelopments are being built with much less car parking space than the past and because there are alternatives, this does not affect the viability of the development.Linked to this, each age group in London except the over 60s drives less and owns fewer cars than the same age group 10 years ago."That means if there is an expected growth in population for London not increasing the capacity of the road network for motor vehicles is not an option"Increase in motor traffic isn't inevitable, it is also determined by policies, and policies like road pricing and freight consolidation will affect traffic.  There is a truism in road planning that "design the road capacity for the traffic you want and that is what you will get"."increasing the capacity of the road network" sounds all very well, but what does it mean?  Would this mean, for example increasing the A4/M4 from 6 lanes to 8 lanes?  Then what happens at Shepherds Bush/Fulham Palace/Hammersmith Rds where a significant proportion of A4/M4 traffic is heading? Do the 8 lanes of traffic come to a grinding halt? There is no way roads through central London can be expanded because the property on each side is far too valuable, not to mention residential objections.The trouble with tunnels is the longer the tunnel, the less traffic will use it and within a dense city like London, it will be very difficult to segment out traffic that just wants to go from "A to B" and can be served by a tunnel.  A significant proportion of traffic at "A" doesn't want to go to "B" but wants to go to "C, "D", "E",  "F"...Anyway, good debate!

Michael Robinson ● 3355d

'You simply aren't correct about the contribution of cars to pollution. As a percentage of total NOx emissions (that is, transport and non-transport sources), diesel cars are the single largest contributor on the roads.'I don't think that we were ever talking about the absolute level of the contribution of cars to pollution just the rate of change.You were claiming that the reason we have seen a deterioration in air quality is because the Government encouraged a switch to diesel. I am sceptical about this because it is only in London that there has been no reduction in emissions and it is only in London that there has been such a significant increase in the bus fleet. Also the replacement cycle is shorter for private motor cars and a new diesel car will have a lower level of NOx emission than an old diesel car. This suggests that whilst private cars may be responsible for most of the NOx pollution they are not the reason why air quality has got worse in recent years and their contribution is probably falling.‘Clearly the overall capacity of the road can be increased by allocating more road space to bikes.’I can’t believe that this is the case. The first thing you are taught when riding a bike in London is to ‘ride big’ and you soon learn to do this anyway. Therefore in narrow roads which are the ones most likely to experience congestion a cyclist takes up just as much space as a car. Bikes will tend to reduce the general speed of traffic – this is something I’ve observed as a cyclist, driver and bus passenger.‘There is also the myth that "improving traffic flow" will improve air quality.  It won't.  The roads in London with the highest average speeds such as major A roads also have lousy air quality and exceed limits.’It isn’t disputed by anyone else that emissions are higher when traffic speeds are lower. There are high emissions next to road where traffic does flow because more vehicles pass along those roads.I’d stress again that I am not against encouraging cycling but it should not be done for the wrong reasons. The idea that a significant number of motor vehicle journeys could be substituted for bike journeys is a fallacy. Private car journeys have been falling in London for some time, probably due to the increased cost of motoring but in recent years this trend seems to have stopped. Some relatively young, able-bodied people who have work that doesn’t involve physical labour or carrying tools and a relatively short regular commute have switched to cycling. However, the vast majority of journeys that are undertaken in the capital could not be substituted with a bike ride and therefore demand for private car journeys will be more and more inelastic from this point. That means if there is an expected growth in population for London not increasing the capacity of the road network for motor vehicles is not an option. Tunnels seem to be well worth considering in this context. 

Paul Corcoran ● 3356d

You simply aren't correct about the contribution of cars to pollution.As a percentage of total NOx emissions (that is, transport and non-transport sources), diesel cars are the single largest contributor on the roads.11% Diesel cars8% Buses8% Rigid Heavy Goods Vehicle5% Light Goods Vehicle4% Articulated Heavy Goods Vehicle2% Coach2% Taxihttps://www.london.gov.uk/sites/default/files/Driving%20Away%20from%20Diesel%20final%20report.pdfIf you have data and evidence to the contrary, please provide it.Also, "heavy congestion" isn't a source of pollution.  Sources are cars, buses, lorries... etcTo illustrate what I mean about overall capacity:- average car occupancy in London during peak hours is 1.3 people per car- traffic planners work on a basis of a bike is 0.2 Passenger Car Units (PCUs).  A HGV is 2.3 Passenger Car Units.So, 100 people in cars at peak times is 77 cars or 77  PCUs of road space100 people on bikes is 20 PCUs of road space, so almost a quarter.So that is a lot of road space occupied by few people in cars.  Clearly the overall capacity of the road can be increased by allocating more road space to bikes.  That means people in cars may be slowed down but that shouldn't be an automatic reason not to do it.  Essentially this is a political decision and with the cycle superhighway schemes Boris has decided that the need to increase road capacity and provide a safe and attractive environment for cycling is more important than the journey time of cars, the majority of which only have one person sitting in them. Regarding the mix of traffic, I agree that large numbers of buses and bikes in the same lane isn't a good idea because both slow each other down.  That is a good case for separate bike and bus lanes.  However buses are different because they stop at bus stops every 100m or so. Goods traffic and cars don't, they generally only stop at junctions and signals.  Cars are really no quicker than bikes for urban roads in London at peak times.  A car may be able to overtake a bike between lights but then it reaches a light and waits behind a long queue of other cars and motor vehicles.  The bike then passes the car and gets to the front of the queue at the lights.There is also the myth that "improving traffic flow" will improve air quality.  It won't.  The roads in London with the highest average speeds such as major A roads also have lousy air quality and exceed limits.  The only way to improve air quality is reduce the number of polluting vehicles on the roads, by switching to non-polluting motor vehicles (which doesn't do anything to change congestion) and simply reducing the number of pollution vehicles.

Michael Robinson ● 3360d

'It is incorrect to blame London's air pollution on buses.  Clearly they are a contributor and the contribution will be proportional to the number of buses.'No it won't because emissions from buses are far higher than other vehicles'What is your explanation for pollution exceeding limits on roads without any bus services? 'HGVs and heavy congestion.I think the argument about bikes and road space isn't particularly convincing. You need to take into account speed as well and it doesn't follow that, just because the average speed of traffic is now around what a cyclist could comfortably travel at, bikes don't slow the general flow of traffic. This is particularly the case with bus lanes as you'd see just by taking more or less any bus in London and travelling on the top deck at the front. If you were to reduce the number of cars by 10% and increase the number of bikes by 15% (to take into account that some cars will be carrying passengers) I'm not sure you would see improved traffic flow or better air quality. Remember you'll still have the same number of more highly polluting vehicles like buses and HGVs and these will now probably be more slow moving and stopping and starting more regularly.There are other benefits that makes encouraging cycling worthwhile such as reduced fossil fuel use, better health and lower noise pollution.

Paul Corcoran ● 3361d

It is incorrect to blame London's air pollution on buses.  Clearly they are a contributor and the contribution will be proportional to the number of buses. However pollution exceeds limits on many roads that don't have any bus services.What is your explanation for pollution exceeding limits on roads without any bus services? There is extensive data available from http://cleanair.london and depending on the pollutant being measured and where it is measured, cars are often primarily responsible.On the point about bikes, as I mentioned, the average speed of traffic in central London hasn't changed for a century.  Motor vehicles do a very good job of slowing down other motor vehicles with no bikes present at all.A back of the envelope illustration: 30 people in cars at average occupancy rates for London will occupy almost 200m of road space.  The same number of people on bikes will occupy about a quarter of that.  Yet drivers think they are slowed down by bikes...And if 10 people in cars take their journey by bike instead, that will free up about 60m of road space and take 10 polluting journeys off the road but you believe it will increase congestion and pollution...?The irony is that for many pollutants, the exposure for someone within a car is greater than someone walking on the footpath beside the road so the driver may be poisoning themselves more than they are poisoning other people."the more road space that is allocated to them, the more you reduce the capacity of the existing network for other vehicles"And is that a problem? On a number of routes in London the number of cyclists already outnumber other vehicles but road space doesn't come near reflecting this.  Allocating space for the most efficient users of space will increase the overall capacity of the road.

Michael Robinson ● 3362d

I'm not disputing that induced demand exists it clearly does. It should not however be wheeled out as a reason never to build a new road. Even in your gloomy scenario in which increased capacity quickly gets congested more people are getting around the capital. The evidence suggests that your contention that vehicles have become more polluting is wrong. Diesel car usage has risen across the UK but it is just London that has seen marked rises in pollutants in the air. The increase in pollutants has not just been in NOx which might be attributed to diesel cars but other types such as particulates which newer diesel cars emit in tiny amounts, certainly less than a petrol car made ten years ago. The reason why London has seen a worsening in air quality that other UK cities have avoided is that our bus fleet has grown far faster than elsewhere. I don't think this justifies a scaling back of expansion of buses in London because they offer benefits that outweigh the harm. However, policy would be misdirected if it worked on the assumption that cars had primary responsibility for our poor air quality. The priority should be accelerating the replacement cycle of the existing bus fleet.I don't accept that saying bikes contribute to pollution is a red herring. They slow the general flow of traffic and the more road space that is allocated to them, the more you reduce the capacity of the existing network for other vehicles. I do still think cycling should be promoted because it offers a whole host of other benefits but the argument that it can reduce pollution and congestion does not reflect reality.We have to accept that the number of journeys of every type is going to increase over the next two decades in London and our medieval road structure will struggle to cope unless innovative solutions are adopted. Technology, including road pricing, clearly has great potential but we should be willing to accept that at some point more roads will have to be built and underground seems like the only option.

Paul Corcoran ● 3362d

"This is the theory of induced demand which in my view is a nonsense"Proof of induced demand is well established with countless examples going back decades so there really is no basis to claim that it doesn't occur.The question is whether it is a good thing or bad thing.  Crossrail, for example, will create induced demand and people will make trips they wouldn't otherwise have made.However building more roads in London doesn't actually "solve" congestion as the roads will just end up congested again, except with more people stuck in traffic.  Is that a good thing or bad thing? Well if the justification for building the roads in the first place was that it would somehow reduce congestion and pollution, then it would be a failure.  If the justification is that it will allow more people to travel as slowly on the roads as they do currently, then it would have met the objectives.I'd argue that it is pointless to try and "solve" congestion anyway as it is a problem without a solution.  In central London there will always be more demands on road space than space available.  The average speed of traffic in central London hasn't changed since the days of horse drawn carriages and that doesn't seem to have affected the London economy.Congestion is just a measure of someone's tolerance to be stuck in traffic and really the focus should be on mitigating the negative aspects of this and ensuring that there are other options for people to get around."more bikes on the road means traffic moves more slowly particularly buses who share their lanes with bikes and this in turn means more traffic and more pollution."Bikes ARE traffic and will overtake cars at peak times in central London in the next few years.  The issue isn't traffic, but the type of traffic as bikes and buses are far more efficient use of road space than cars.I agree with you that lots of bikes and buses in the same lane just ends up slowing both down, not to mention safety issues, but that is just an argument for separated bike lanes and reallocation of road space to create these.Your point about bikes somehow increasing pollution is a complete red herring.  The reason pollution has increased despite lower volumes of motor vehicles is that the vehicles themselves have become more polluting.  Government encouraged the switch to diesel over petrol but did not appreciate (or ignored or were mislead) about the different pollution characteristics of diesel.The only way to address this is to reduce the number of polluting vehicles.  Making it easier to drive polluting vehicles won't do this.  That would be like trying to solve obesity by making it easier for people to stuff themselves with food that makes them obese."We have to increase the capacity of our transport network"And a way of doing this is to discourage the most inefficient users of road space, low occupancy private cars."how much technology can help reduce London’s problems"So the technology you haven't mentioned is demand management through road pricing.  Think of it as Oystercard for motor vehicles with the potential to charge every journey by vehicle type, time and route.  Pricing can be used to move less time sensitive traffic from peak to off-peak and encouraging other journeys to be made by other modes.  It is the sort of thing done for other modes of transport so it is about time roads  caught up with this.  The Evening Standard had an editorial last week calling on the mayoral candidates to propose road pricing schemes so it is becoming political mainstream,

Michael Robinson ● 3363d

‘Building more roads, whether underground or overground is not the answer to traffic congestion because they just get filled up by the extra vehicles they attract onto the road’This is the theory of induced demand which in my view is a nonsense. Nobody says we shouldn’t build more houses because they will just attract people to live in London.The problem with London is that we have reduced our road capacity over the last decade or more. Handing over road space to buses and cyclists has mean that despite there being a decline in the number of motor cars on the road and a substantial reduction in the emissions these cars make we have seen increased congestion and worsening air quality.  I am not against buses and cycling and believe it is right to encourage them but we should not pretend doing so reduces congestion and pollution. A cyclist may argue he creates zero emissions but in practical terms more bikes on the road means traffic moves more slowly particularly buses who share their lanes with bikes and this in turn means more traffic and more pollution.Whether tunnels are the answer I am not yet totally convinced. We have to increase the capacity of our transport network and there is a logic to moving more of the system underground. However, I think TfL is being very alarmist with the numbers they are using to justify the massive investment that would be required to build these tunnels. The major unknown factor in all of this is how much technology can help reduce London’s problems. Better emissions technology should at some point reverse the trend of deteriorating air quality and in twenty year’s time we probably won’t just be talking about driverless cars and collision free motoring but they will be a reality.

Paul Corcoran ● 3363d

The maps in the article seem to be all the information there is on this 'plan' at the moment. However, let's be realistic and remember that the next mayor is just going to rip up these have-baked back of an envelope ideas that Boris Johnson has promoted himself in the face of objections from anybody at TfL who knows about transport planning.Building more roads, whether underground or overground is not the answer to traffic congestion because they just get filled up by the extra vehicles they attract onto the road. Encouraging more cycling use of public transport is the only way forward for London.

Mark Evans ● 3364d

Can the editor please give us some links to the TfL maps for (1) Cross City Tunnels - with little circles which might be entry points along the route? and (2) Key Corridor Tunnels - which are nine short tunnels? The maps are rather confusing.....

Una Hodgkins ● 3367d

There is a report on ChiswickW4.com about plans Boris has for two mega tunnels across London. These won't directly affect Hammersmith but a project here still seems to be the way forward as they clearly see tunnels as the long term solution to London's traffic congestion issues.

Ellen Kearney ● 3368d

Promises to be interesting and I'm aiming to get out of work quickly to be there. Hopefully both sides of the debate will be adequately represented.

Paul Corcoran ● 3599d

Boris has come at an opportune moment for seeking a legacy: during the reign of this Conservative government the whole of London (as the UK) has been turned over to proposals from developers... I rest my case.

Una Hodgkins ● 3714d

Not sure of the relevance of this as Boris will be long gone before we even get to talking about the nature of any building around the site of the flyunder.For the record I would dispute that Boris Johnson works for the benefit of financiers and developers. Over the whole course of his career he has worked tirelessly and single-mindedly for the benefit of Boris Johnson.He is talking about this scheme now towards the end of his term in office because he genuinely thinks it might be a good idea and wants it to be seen as part of his legacy.

Paul Corcoran ● 3714d

"Boris Johnson works for the benefit of financiers and developers. He is their agent."In Hackney they're trying to take him on, only to find that the cards are rigged in the favour of huge insensitive developments and local democratic opinion can be ignored. Does anyone think that wouldn't be the case in Hammersmith?http://news.hackney.gov.uk/save-shoreditch/

Thomas Barry ● 3716d

Boris Johnson works for the benefit of financiers and developers. He is their agent. He will kill this project if he promotes their ROI requirements as his first priority, instead of attempting to enhance Hammersmith Broadway for existing residents.

Una Hodgkins ● 3717d

Think that is a good idea. It would also have the added benefit of ending the need to go all the way round Hammersmith Broadway to turn into Fulham Palace Road when you are coming from the west. In turn this would make crossing from the tube station towards King Street much less of a nightmare.That said now that Boris is talking about tolls for the flyunder suggests he hasn't really thought this through. The flyunder would only work if vehicles are encouraged to use it rather than charged more.

Paul Corcoran ● 3717d

If you take it that one of the main aims is to reopen the vista around St. Paul's Church and give that area greater access to the river you could have a two way traffic flow along Hammersmith Bridge Road and make the section of the Talgarth Road up to Butterwick two way again. Access to King Street could me made bus/access only in normal business hours. This would remove the pinch point at Glenthorne Road/ Hammersmith Grove and dramatically reduce the amount of stationary traffic in an area that is about to become mainly residential.

Andy Jones ● 3731d

"Just how can they remove it?!"That's precisely what I've been wondering.  You'd need significant reduction in capacity on all the routes approaching it, particularly Fulham Palace Road and Hammersmith Road, to have a chance.  I'm assuming they'd want to do something logical like remove the north west corner between the tube stations, which is the most intrusive part, but that means pushing the traffic round the eastern side reconfigured as a two-way street.One of the mistakes inherent in the 'flyunder' argument is that the flyover carries vastly more traffic than anything else in the area and thus deserves the bulk of the funding, which is untrue and based on the erroneous assumption that the A4 is used for people driving into central London rather than for shorter journeys within west London that use part of the A4 at times.  Finding alternative means of transport for those people would be very useful too.

Thomas Barry ● 3740d

Yes, I agree. The problem is that I don't see how they can remove the gyratory because it deals with all the traffic APART FROM flyover traffic. Just how can they remove it?!

Una Hodgkins ● 3741d

'ideally no further than the footprint of the existing flyover'Which is mostly over roads, or between roads - that was just one of the bits of nonsense.  You'd have to remove some of the surface roads, too, which isn't a bad idea and implied in the suggestion that the gyratory would be removed.

Thomas Barry ● 3741d

The original studies need a careful re-think about how much land needs to be redeveloped - ideally no further than the footprint of the existing flyover - to pay for the new tunnel and demolition of the flyover.

Una Hodgkins ● 3742d

I believe there's a hidden message in that, which is that Labour actually want the gyratory work done and want Boris to take the rap for not pushing the flyunder (he went silent as soon as the Tories lost, I note).Notably there's nothing new and nothing to address the fact that the original studies were total nonsense.

Thomas Barry ● 3742d

Please to see from the Hammersmith Today newsletter this week that this plan now has the backing of the Labour administration at H&F and that they are encouraging Boris to get a move on.

Paul Corcoran ● 3744d

Standard is reporting that an orbital tunnel is being considered. Moving stuff underground was exactly what was being considered just as the Tokyo property bubble burst - it was then called 'Geo-front.' Hard to see any alternative for a growing city lumbered with a medieval street plan.http://www.standard.co.uk/news/transport/mayor-sets-out-plan-for-22mile-ringroad-tunnel-under-london-9354896.html

Paul Corcoran ● 4001d

'according to a post on Twitter'? Really?My recollection of what Boris said is that the Flyunder would take 3-4 years to build not that it would be built in 3-4 years time. If you have any proper evidence that he didn't let's see it.

Ellen Kearney ● 4041d

"According to a post on Twitter, Boris has just said on LBC that the flyover will be gone to be replaced by a tunnel within 4 years."Yeah, right.  Yesterday's LBC phone in with Nick Ferrari contained the following exchange where Boris attempts to row back significantly from that position:--NF: How's the Hammersmith Flyover going?BJ: Aha! Doing well.NF: Is it?BJ: YesNF: That's what's made you decide not to go in [back to Parliament] last time.  Is it, have we got the plans, is it all green lighted?BJ: Ah, well, not green lit, we're not quite there yet, but it is just one of the series of amazing things you can do to improve the infrastructure of the city…NF (over): When will, when will I be able to drive under Hammersmith and not fly over it?BJ: Not in the next five years, but probably in the next fifteen yearsNF (incredulous): FIFTEEN YEARS?  Ay, ayBJ: Well come on, these things are not done overnightNF: No, I'm sureBJ: ..not done overnight.  Let's go to Dan in West Hampstead--TfL's budget planning is five years to 2020/21, so what Boris is saying there is that the 'flyunder' isn't in that plan and therefore won't happen before 2020/21 at the earliest.  Perhaps if the council's plans weren't full of inconsistencies and dodgy maths it might have more of a chance.

Tom Barry ● 4041d

"This has to be land belonging either to TfL or to Hammersmith Council"Not entirely, there's an explicit disclaimer:"The project may entail acquisition of private land and buildings. No allowance has been made for acquisition of land, site assembly and land ownership."Given that the Masterplan involves razing almost everything between Angel Walk, King St. the gyratory and Worlidge Road except the church and the Hop Poles (but including St. Paul's school). I'd be surprised if that didn't involve compulsory purchase of private land somewhere, even if a private company is tasked with assembling the land."Can I ask, please, what is your evidence that Capco is involved? "At least one of the geotechnical/buried services studies was commissioned by them, but mainly this bit from the draft feasibility study:'In order to drive and steer the project towards its challenging timeframes a number of workgroups were established....The second group was a technical group (known as the taskforce) which met on a monthly basis throughout the project. This group was attended by the three neighbouring local authorities: Hounslow, Richmond and Kensington and Chelsea. Other stakeholders included the GLA, TfL, WLLD, Hammersmith BID, Capco and Halcrow who were the engineering specialists commissioned to undertake the geotechnical study.'So the technical group sensibly involved all the public bodies involved, plus the consulting engineers, plus the local business improvement district and the architects who came up with the plan.  And Capco, for some reason.  Funny, that."Hey presto! Lots of money for a "short" or even a "long" tunnel"The difference in estimated developed area between short and long is only 52000 sqm - 'short' is 309,000, 'long' is 363,000.  That tells you most of the major development is likely to be concentrated in the centre, which indeed it is - south of King St and north of Worlidge Road, on the bus station site by Butterwick and by the Ark.The feasibility study is quite clear on the real aim here:'The illustrative masterplan, as well as showing development on land freed up by the removal of the A4,also shows opportunities to bring forward development on neighbouring parcels of land. This includes Hammersmith Bus Station, part of the southern side of King Street, Landmark House and the West London Magistrates Court.'That's why the actual length of A4 freed up is immaterial, the actual business is concentrated elsewhere.  It's not actually about the flyunder at all.

Tom Barry ● 4044d

Good, Tom. We are looking at approximately the same type of project for blocks of luxury apartments, although perhaps in slightly different places. The exact location doesn't matter too much. You say: "It's mainly about overdeveloping the south side of King Street". Where are you thinking of, exactly? This has to be land belonging either to TfL or to Hammersmith Council. Of course the Council wants to knock down Riverside Gardens, Aspen Gardens and any other estates - it has recently signed a 35 year contract with Stanhope plc to do just that.  I am deliberately breaking the apparent link between the length of the tunnel and the width of the Great West Road to be given over to new development. These are two completely unrelated parameters in my scenario: if you magically remove "the traffic from the A4 to the gyratory and the... local traffic", as we both say, then you can have a "slim-line" Great West Road and twenty-odd new blocks stretching one mile along the south carriageway to Hogarth Roundabout, close to the river. Hey presto! Lots of money for a "short" or even a "long" tunnel. But instead a "Berlin Wall" of new apartment blocks separating Hammersmith from the river far more effectively than the little flyover ....Can I ask, please, what is your evidence that Capco is involved? We simply have to kick out the current administration on 22nd May before they puncture every part of Hammersmith with high-rise blocks.

Una Hodgkins ● 4048d

"But Boris has been convinced by the developers that it can be done"No, he hasn't.  He's fallen for some shiny pictures and spin, as usual.  He's not interested in practicalities and doesn't realise the importance of traffic from the A4 to the gyratory and the volume of local traffic movements.I have actually FoI'd the GLA for the evidence Boris was relying on and any TfL reports and they initially tried to tell me he was relying on the LBHF studies which were written and published after his LBC interview.  This is obviously impossible so I've queried it.  In response they can't or won't tell me what Boris was relying on (a 'paper copy' of an unknown document held by LBHF, apparently), so I'm assuming he was bigging it up as usual."So I think that the "Flyunder" is not about a tunnel at all - or at least only incidentally"You're right, in that it's mainly about overdeveloping the south side of King St.  The actual amount of developable land on the A4 itself is, in comparison, quite small (compare the amount of developed area in the two options - the short option, which frees next to no land (your 'mile of the north bank' still has the same amount of road on it, by the way), still has substantial development pencilled in).  The whole bit about reconnecting Hammersmith to the river is just nonsense, though.The Earl's Court developers Capco are heavily involved in the flyunder studies so it's a safe working assumption that it's all being done at the behest of developers, such is the degree of regulatory capture of London's government at the moment and the sheer arrogant incompetence of the assumptions about traffic flow.  Surely we deserve better?

Tom Barry ● 4049d

I should have added a bit more to my previous post. After years of reading the PR spin from Hammersmith Council, I look for alternative motives for all their stated objectives. So I think that the "Flyunder" is not about a tunnel at all - or at least only incidentally. The "Flyunder" is a Trojan horse for huge new money-making redevelopment on the southern carriageway of the Great West Road, as I outlined before.  Hammersmith Council wants more and more and more luxury apartment blocks and Boris wants the capital receipts from selling TfL's land. Yes, we have to somehow get rid of the traffic from the gyratory system. But Boris has been convinced by the developers that it can be done. On LBC Radio he said candidly: "We've been listening to this for months and months thinking, 'come off it this is never going to work', and actually it is brilliant. It adds up. It's a most fantastic scheme. We're going to tunnelise the flyover......" With receipts from developments lining the Thames on the north bank for a full mile, as I have outlined, it does indeed "add up". The short tunnel could be paid for easily.Remember that Hammersmith is the Council which has given itself permission to redevelop 77, yes seventy-seven, acres of "Central London" at Earls Court. No one except the protesters mentioned monumental traffic snarl-ups along the Earls Court and Warwick Roads, and they of course were brushed aside. The "Flyunder" will be a piece of cake compared with Sir Terry Farrell's "Five Villages" project.

Una Hodgkins ● 4049d

There's no need to get so agitated Thomas!I was hoping for a better environment around Kelmscott House but I understand why the plans that have been presented don't allow for that. Nobody was lying to us about this.You have to accept the fact that whatever else happens, Hammersmith will be a lot nicer if it didn't have a whacking great flyover in the middle. As for value for money - doesn't the report show that the project will generate a surplus? I couldn't follow the latter part of your post. You appear to have become so aerated you lost coherence but it seems your alternative to the flyunder is the abolition of traffic. Good luck with that.

Ellen Kearney ● 4049d

"This plan doesn't deliver that"Does this shake your confidence in the competence and honesty of the people proposing it?"it will make a section of the centre of Hammersmith a lot more pleasant to be around."What 'section'?  How much of the centre of Hammersmith is made a lot more pleasant for our 250 million quid?  Without reducing traffic on the gyratory sufficiently to remove the south west quarter and narrow the A306 considerably it's about 200 yards south of the church.  Value for money?"Nobody has mentioned the air quality benefits"Yes, it all comes out of the portals in easy to breath lungfuls, just behind Kelmscott House.  Also given that they have not studied a viable change to the gyratory that reduce traffic on it the air quality there presumably stays exactly as it is, i.e. rubbish.  The flyover doesn't carry all the traffic in Hammersmith.What the current study does show quite clearly is that you can't have the current levels of traffic through Hammersmith *and* the nice human-scale town centre from the pictures, as there isn't an option on the table.  So it's time to pick what you want - the traffic or the town centre.Personally I vote for the nice town centre but if you think you need to keep (or increase) the traffic good luck to you, but don't complain about the noise and the air quality and the 230m trench in William Morris's back garden, or the continuing gyratory system or the choked surface roads, because that's what pretending you can't do anything about the traffic gets you.  There is no good alternative that involves keeping current or increasing levels of motorised traffic through the area.Alternatively, look the traffic in the and say 'do you know what, we don't actually need this in our city' and then things become a lot more feasible.  As it is you're proposing spending the thick end of quarter of a billion pounds reinforcing the mistakes of 60 years ago when everyone thought the future was ceaseless urban mobility in private cars.  We've grown out of that now, with the possible exception of Hammersmith and Fulham Council and the Mayor of London.

Thomas Barry ● 4049d

Paul is right. I said earlier in this thread it would be great to see Kelmscott House return closer to being the haven of urban peace it once was. This plan doesn't deliver that but it will make a section of the centre of Hammersmith a lot more pleasant to be around.Nobody has mentioned the air quality benefits. In a tunnel the air will be filtered but with the flyover fumes and soot are spread like confetti all over the surrounding area.

Ellen Kearney ● 4050d

Thomas, I had to chuckle at your argument about option 1a unpopular because it was the first choice of a relatively small number of people. It's a bit like saying if I was offered a large steak and a small steak and chose the former that would prove I wouldn't accept the latter. No amount of double speak can alter the fact that in Hammersmith this idea is very popular.On the images presented for the schemes yours are more useful than the ones in the report. I think a big mistake has been made in providing misleading and confusing visualisations of the scheme. Nevertheless, try thinking of it the other way round i.e. there was a proposal to dig up a tunnel and replace it with a flyover. Even LBHF wouldn't be able to drum up pictures that would make that look attractive. More realistic plans have to be put to the public before this project goes any further. I believe, despite your alarmism, they will still prefer what's on offer to the alternative of a flyover.

Paul Corcoran ● 4050d

"What the illustration does NOT show is the line of new blocks continuing west all the way to Hogarth Roundabout"Except that as the feasibility study states, the longer the tunnel the less traffic will use it. Neither of the two remaining options start at Hogarth despite that being what was originally sold to the public, all of which means you need to retain four out of the current six lanes of A4 east of Hogarth for the 50% of A4 traffic that still has to go on the surface through Hammersmith, which means no room for any substantive development.  Even then the numbers are seriously against the long project because most of the development income comes from off-route sites in the centre of Hammersmith, south of King St. and around the Ark, which are possible with either option.That leaves only the short option on the table where the numbers nearly add up (if you forget the bits they haven't counted, like removing the flyover and buying the land) which puts six lanes and a honking great tunnel portal outside the Town Hall and Baron's Court Station and obviously isn't on any of the CGIs because the residents would twig that they've been sold a pup.All they've proved with this exercise is the following:The longer the tunnel the more popular it is and the more land it can release but the more expensive it is to build and the less traffic will use it which requires a bigger residual surface road network which means it releases less land and ends up not providing much of an improvement in the absurdly congested traffic situation in Hammersmith which is what the public actually seem to want to get rid of.As it turns out you can have a nice town centre or a road junction handling 150,000 vehicles a day, but not both.  The council, the BID and their arrogant architects, who worked everyone up into a frenzy before doing any meaningful study of this appear to think you can, which is why they now look phenomenally stupid and are punting the whole mess over to TfL.  It really has been amateur hour down the Town Hall.

Tom Barry ● 4051d

The illustrations show that the Great West Road has been shrunk to a two-lane local road, and pushed north against the Town Hall and Riverview Gardens, the adjacent Council estate. This leaves empty the land which was the south carriageway of the Great West Road. This runs of course from the end of the flyover to Hogarth Roundabout and it belongs to TfL. This one-mile long strip of "riverside" land will be used to pay for the tunnel, as follows. The illustration shows five x new seven-storey blocks, rather thin ones running east of the Town Hall, hemming in and dominating the north side of Furnivall Gardens. What the illustration does NOT show is the line of new blocks continuing west all the way to Hogarth Roundabout, i.e. a total length of one mile of new "luxury apartment" blocks! This vast redevelopment has not been discussed (certainly not by Hammersmith Council!) Why would they want to tip their hand? The line of new blocks will be more like three times seven, i.e. twenty-one new apartment blocks! And they will all be less than 100 yards from the riverside, and thus worth megabucks for the penthouses. They will dominate the ends of Rivercourt Road, Weltje Road, Oil Mill Lane, etc.... We hadn't thought of this land being used. But now you see where the money for the Tunnel will come from, don't you? It does indeed "add up", as Boris said.Of course Hammersmith Town Hall is carefully preserved from this new "Berlin Wall" of development: instead the edge of Furnivall Gardens is taken up to the single carriageway and a fountain and new lake are created in front of the Mayor's parlour. The lake is supposed to remind us of Hammersmith Creek which actually runs underneath it. Incidentally Riverview Gardens will have no River View at all, but then they're only council tenants anyway.

Una Hodgkins ● 4051d

"You are listing negatives that everyone is aware of but do not provide a reason not to consider a flyunder."Considering the pro- lobby has an entire council, BID, Mayor and TfL at their disposal and has demonstrably conned the people of Hammersmith, a little balance and critical analysis doesn't go amiss here, surely?  Assuming I can get images to work, here for balance are a couple of pictures knocked up by me showing what the engineering report actually proposes for Option 1a, your cut and cover tunnel replacing the flyover:Western portal behind Town Hall:Eastern portal across Gliddon Road:How's that for severance?Also the council's own survey found that starting the western end of the tunnel at the Town Hall had 1% of support compared to 39% for Hogarth Roundabout, so they cannot claim public support for Option 1a, and since you've repeatedly said that Option 3a (Chiswick-Earl's Court) is impossible and won't happen, I'm not sure where you go from here, Paul.  Surely the council should re-run the consultation based on the two options, although given that this will show Option 3a is the one the public want, which is impossible on financial grounds, traffic grounds and will have Chiswick up in arms they might well be best advised to bury the whole idea."It is too early to adopt a stridently fixed position on details as you are doing."Equally, by your argument, it's too early to take a fixed position that it's possible to reconcile a 14% increase in traffic by 2031 with removing a significant amount of traffic from the surface streets of Hammersmith, given the large amount of time and effort that has been put in so far which has clearly shown that it isn't.

Tom Barry ● 4053d

Once again a reminder that this is a report advocating a feasibility study. If your melancholic predictions for project cost are realistic this will be confirmed by the subsequent report. It is too early to adopt a stridently fixed position on details as you are doing.The current report suggests a surplus would accrue from this option which, I’ll concede, does seem a tad optimistic but in the same way that your analysis is too negative. They are claiming that a substantial amount of commercial space and 2,000 residential units will fit into the available space along with a significant amount of relandscaping to make the area more attractive.  Even if you substantially reduced the amount of space to be created and take away land acquisition costs you still will have made a significant dent in the overall project cost. On ‘Engineering report negativity’ the new that digging a great big hole in the ground will be very disruptive shouldn’t be a surprise to anyone. Neither has anyone claimed the flyunder makes the Hammersmith gyratory disappear (although I’ll admit the pictures are misleading). The removal of the supports to the flyover should allow more flexibility in planning traffic in the area. You are listing negatives that everyone is aware of but do not provide a reason not to consider a flyunder.

Paul Corcoran ● 4056d

"Option 1a is the minimum option considered, it a like for like replacement of the Flyover in tunnelled form. As such it is the cheapest of the options detailed in this report, however it is also likely to be cause massive construction disruption due to the Cut and Cover method of construction and the required depth of the excavation due to sub surface obstructions. It is likely that this is cause long term disruption and traffic congestion for the duration of its construction. In addition to this option 1a does not relieve traffic on the gyratory, only the east-west traffic along the A4. "That's not me being negative, by the way, that's the engineering report.  Stop trying to shoot the messenger, Paul.  Why spend all that money and disrupt the entire area for years without relieving traffic on the gyratory, which is the real issue here?

Tom Barry ● 4056d

"Also even if there is only 100 yards of land freed up for redevelopment given where we are in London that would provide cash to make a substantial dent in the £218mn cost making it look like a bargain."Um, the land in question is supposed to be the green space round the church, rather than redeveloped.  It wouldn't make much of a dent in £251m (revised figure using the correct optimism bias in the latest document) either.Latest documents are interesting, not least for the quiet way they were snuck out.  If we ignore the long tunnel options from Chiswick, which lose money and don't work, the favoured 'option 1a' is a cut and cover tunnel starting just behind the Town Hall in a 25mx230m cutting roughly where the subway is and extending halfway down the north side of Furnivall Gardens.  There's then a 25m wide swathe cut and covered through Hammersmith south of the Broadway, deep enough to go under the railway, swinging south east and coming up roughly at Gliddon Road.  That means another 25mx230m trench with four lanes of traffic in it cutting off the entire eastern part of Hammersmith plus the college from Baron's Court station and the Palliser Road area to the south.In other words, any regained connectivity in the centre (which is moot, as it requires the gyratory to be removed and no one's worked out how to do that) is offset by new severance at the edges.There isn't a lot of land freed up by this, either - a bit north of Furnivall east of the trench, a bit by the Ark west of the trench, some nebulous idea about narrowing the road from the west to the gyratory.  Most of the actual redevelopment, including two quite tall buildings, is being done off the line of the road, much of it on the south side of King St. where about 2/3 of the Hop Poles is the only building left standing.Which makes it rather odd that the sums don't include actually buying the existing privately owned buildings up, or demolishing the flyover or removing the gyratory, nor do they explain what traffic restraint would have to be imposed across West London for the three years of construction (they admit that it's necessary and that the construction phase is hugely disruptive).That does ensure that the numbers come out slightly positive, however, but you can prove anything by ignoring facts.  In short, it's complete BS.  Go and read it and try and poke holes in this.

Tom Barry ● 4056d

The flyunder report has been published here:http://www.lbhf.gov.uk/Directory/News/Flyunder_report_published.asp#4If you are in any way discouraged by Thomas Barry's relentless negativity about this plan take the time to read it and you will find it reassuring. In a nutshell the report makes clear that the cost/benefit ratio of the shorter 'cut and cover' option is much more favourable than any of the others. This more limited project is not what people generally would have liked but, according to the report, may actually be self funding and would result in 2,000 new homes in the area as well as transforming Hammersmith Town Centre.

Paul Corcoran ● 4056d

There will be a significant amount of disruption if the flyover is rebuilt probably just as much with the flyunder.Also even if there is only 100 yards of land freed up for redevelopment given where we are in London that would provide cash to make a substantial dent in the £218mn cost making it look like a bargain.

Ellen Kearney ● 4061d

"According to a post on Twitter, Boris has just said on LBC that the flyover will be gone to be replaced by a tunnel within 4 years."Boris is, as is typical of him when faced with a bad idea, somewhat jumping the gun, given that LBHF's commissioned study effectively says the only option that works is a straight burial of the existing road, which involves 3 years of severe disruption, costs £218m and frees up for redevelopment all of about 100 yards of land just south of St. Paul's Church.  The two other options for long tunnels starting in Chiswick are eyewatering expensive, push more traffic onto the gyratory, require a large remaining surface road along the A4 corridor to handle the 40-50% of traffic which wants to come off at Hammersmith, as well as causing three years of severe disruption.  Notably Boris claimed it would cost '£1.7bn' which is probably a misspeak for the £1.2bn cost of the two long options which the feasibility study essentially rules out, so he's thinking big and tripping over the detail.It's time the council stopped lying to Hammersmith about this bizarre proposal and accepted it's not going to happen unless something goes seriously wrong in the mechanism of London government.http://democracy.lbhf.gov.uk/documents/s46546/final%20select%20committee%20report%20v3.pdf

Tom Barry ● 4064d

According to a post on Twitter, Boris has just said on LBC that the flyover will be gone to be replaced by a tunnel within 4 years.

Paul Corcoran ● 4071d

Paul, I would expect that this proposal may be quite popular in Hammersmith but less so in Chiswick- especially if the tunnel emerges West of the Hogarth Roundabout.At this stage I think it is unlikely that the Government will want to fund such a scheme.

David Giles ● 4176d

As I said on the Chiswick forum it is hard to know just where public opinion stands on this. The LBHF site feedback is very positive but neither this forum (which is admittedly very quiet) or the Chiswick one give any indication of strong local support.

Paul Corcoran ● 4176d

I wonder how much it would cost and if TfL (or we the taxpayers) could afford it ?The comparable Big Dig Road Tunnel Project in Boston had some serious cost and schedule overrun problems." The Central Artery/Tunnel Project (CA/T), known unofficially as the Big Dig, was a megaproject in Boston that rerouted the Central Artery (Interstate 93), the chief highway through the heart of the city, into a 3.5-mile (5.6-km) tunnel. The project also included the construction of the Ted Williams Tunnel (extending Interstate 90 to Logan International Airport), the Leonard P. Zakim Bunker Hill Memorial Bridge over the Charles River, and the Rose Kennedy Greenway in the space vacated by the previous I-93 elevated roadway. "Initially, the plan was also to include a rail connection between Boston's two major train terminals. The official planning phase started in 1982; the construction work was done between 1991 and 2006; and the project concluded on December 31, 2007, when the partnership between the program manager and the Massachusetts Turnpike Authority ended." The Big Dig was the most expensive highway project in the U.S. and was plagued by escalating costs, scheduling overruns, leaks, design flaws, charges of poor execution and use of substandard materials, criminal arrests, and one death. "The project was originally scheduled to be completed in 1998 at an estimated cost of $2.8 billion (in 1982 dollars, US$6.0 billion adjusted for inflation as of 2006). "However, the project was completed only in December 2007, at a cost of over $14.6 billion ($8.08 billion in 1982 dollars, meaning a cost overrun of about 190%)as of 2006. The Boston Globe estimated that the project will ultimately cost $22 billion, including interest, and that it will not be paid off until 2038." As a result of the death, leaks, and other design flaws, the consortium that oversaw the project agreed to pay $407 million in restitution, and several smaller companies agreed to pay a combined sum of approximately $51 million."Source: Wikipedia

David Giles ● 4179d

Hammersmith residents are overwhelmingly in favour of a flyunder to reunite Hammersmith, split asunder by the flyover and the A4/M4 sixty years ago.Major cities all over the world are now driving traffic underground, the engineering is well understood, and above ground becomes free of thundering traffic, intense noise and much pollution.

Rosemary Pettit ● 4179d

Interesting debate on this matter on ChiswickW4.com board. Consensus seems to be very much against. Yet the comments on the LBHF page suggests overwhelming support. Hmmm.http://www.lbhf.gov.uk/Directory/News/hammersmith_flyunder.asp

Paul Corcoran ● 4180d

On Wednesday 9 October there's a stakeholder 'summit' at 7pm at the Town Hall. All those interested in the Flyunder are welcome.

Rosemary Pettit ● 4230d

I was in Kelmscott House on Sunday as part of the Open House Weekend. William Morris would have been traumatised to see his beautiful garden and peaceful riverside home rent asunder by a massive great motorway and would be a passionate supporter of confining traffic underground.

Ellen Kearney ● 4230d

West London Link Design of architects, in conjunction with Halcrow engineers and Hammersmith BID, is offering a second exhibition of plans and designs for the proposed tunnel between Hogarth Roundabout and Earls Court - in Lyric Square on Saturday,13 July.www.hammersmithsociety.org.uk

Rosemary Pettit ● 4321d

Have always wondered why the road system in this area is so appalling and out of date, this scheme looked wonderful and would be very interested to hear about the viability.  Why is there not much wider discussion about traffic problems, why no tunnels under the river?  Would some visionary tell me what is worth preserving in Putney High Street, or some other solution to a problem that is 30 years old in my personal experience.  Even a cable car solution would help.  The sheer number of bikes on the circular system in Hammersmith and going over Putney Bridge is lethal.  As for preserving the monstrosity that is the flyover, you almost lose the will.

Susan Kenel ● 4333d

It can't happen soon, it would be a long tunnel. And it will be a big job to get the financing in place. The next step is a feasibility study.

Rosemary Pettit ● 4343d

The article just published on this site says that a £60 million contract has been awarded for the upgrade of the flyover so it's not going anytime soon.

Danny Kopech ● 4343d

Hi Matt, do you know the situation with land ownership?

Paul Corcoran ● 4350d

Speaking as one of the architects I am pleased to hear the debate that has occurred and the positive responses we have received.The purpose of the exercise is to reconnect Hammersmith with the river, to improve the local environment, and to investigate what the best way of replacing the flyover is, before that day comes.We are keen to get public opinion and we are collecting responses on the comments page of our website: www.westlondonlink.com. Please feel free to leave your thoughts.

Matt Hedges ● 4356d

Unfortunately Paul this issue is already starting to be politicised. Hammersmith and Fulham Council are the personification of the devil in the view of the left so anything they support must be a bad idea even if in this case it was to make Hammersmith a much more pleasant place to live at minimal or no cost to the taxpayer.

Danny Kopech ● 4358d

There are three ways for the traffic to go - over, under or through. Most rational people would say that under was the best option and through was the worst. The area has some of the highest property values in the world so it does raise the possibility that 'under' can be part funded by the value of the land above the tunnel.Although traffic volumes are falling and hopefully continue to fall the A4 will remain one of the two main east-west routes across one of the most populous cities in the world so it is never going to go away until we invent flying cars. Therefore some practical thought needs to be given to how it will be managed.

Paul Corcoran ● 4360d

"If it was to come off it would have the potential to transform this part of West London."Well, it's not going to come off, so stand down.  Why on earth would we want to spend hundreds of millions entrenching what is basically an urban motorway rather than doing the sensible 2013 thing of recognising that urban motorways have no place in inner London above, on or below ground and proceeding accordingly?(speaking as someone living a mile or so west who would see absolutely no benefit from wasting my taxes like this)

Thomas Barry ● 4361d