Foster & Partners / Delancey temporary bridge proposal

Bridge proposal

• Raised temporary deck envisages crossing for vehicles, pedestrians and cyclists on 2 levels.
• River traffic could pass underneath.
• Costs believed lower and timescale significantly faster than previous plans.
• Partial dismantling and offsite refurbishment of the existing structure while temporary structure in place.
• Transport Secretary given outline brief by H&F Council Leader on 25th November.

There’s been generally positive comment in the press and social media, and we were particularly pleased to see our favoured approach of offsite construction/restoration being embraced, which should improve the quality of the end result.

Funding

Since the public Task Force meeting in October, there have been snippets of gossip from behind the scenes, but little significant  progress to report. TfL have been instructed to pay for a temporary ferry river crossing, and to contribute £4M towards the bridge stabilising work, drawing from their recent £1.8B government emergency funding.

Central government has now promised to fund the project, conditional on a substantial contribution from the local authority.  LBHF report that funds are not available to meet this demand.  The Hammersmith Society and others are pressing the government to take the long view, and release the Bridge funds now, and negotiate separately with the local authority,  and this is set out in our letters to the Task Force chairman and the Secretary of State for Transport, as previously published.

Enquiries to LBHF and other parties have revealed some further context to the funding problem.  We understand that Hammersmith became involuntary owners of the Bridge in 1985, when the government abolished the GLC (Greater London Council); there is no record of a condition audit taking place at the time, and no maintenance arrangement accompanying the gift, which was perhaps a mistake.

In normal circumstances structural repairs to the bridges over the Thames have been paid for by TfL, with costs of a fraction of the c. £150M budget for Hammersmith Bridge;  this very substantial cost arises largely from the design of the structure with cast iron, and design restrictions on the repair methods imposed by Historic England Grade ll* listing status. 

 Letter to Grant Shapps MP, Secretary of State for Transport

Letter to Baroness Vere, Chair of Bridge Task Force

Letter to Dana Skelley, Director of Bridge Task Force

We’ve made suggestions borne of our various architectural & engineering experiences, and feedback from members who contributed, balancing aesthetics, cost-effectiveness, speed of the works vs. longevity & value to the public. 

We think the repairs might be done more quickly and cheaply, and the result might last longer and be more useful as a bridge, if the slightly modified approach were taken, as outlined.  As an alternative, we’ve also dared to think the unthinkable given the proposed closure duration and costs, and suggested bridge replacement. An architectural competition could be held to decide how to best reuse what is there, but make it fit for the next century as Bazalegette did to the 1827 original, back in the 1880’s.  As we’ve said, this need not involve a total loss of the iconic appearance; it would be up to innovative designers to come up with the solution – we’ve already seen ideas coming from local architects and engineers.

With huge sums of central Government capital and revenue expenditure being regularly announced, the cost of solving the Hammersmith Bridge problem seems small by comparison, and given the considerable inconvenience already endured both sides of the river by some of the most vulnerable members of society, the project deserves immediate and full financial support.

Our report on the meeting has to tread carefully to resist the winds of political bias which seem to be jeopardising project navigation. The exchange of letters between the chairman of the Task force and LBHF reveals the entrenched and opposing positions of government and local authority concerning the funding of the bridge repair programme. At the meeting the Task Force chairman declared that the government is ‘completely ready to fund the entire project subject to local contribution’ – the proportion of this contribution was not defined – while the LBHF deputy leader reported that substantial local authority contribution has already been paid out for the bridge work to date, and LBHF could not afford any further funding. 

Alongside the funding impasse, the meeting provided an excellent explanation of the bridge problems, the anticipated repair works, the investigations in progress, and proposals for temporary pedestrian crossings.

A summary of the current critical issues:

• Project funding: government funding is confirmed conditional on LBHF contribution; LBHF and TfL have no funds available to contribute. TfL to fund the ferry crossing and contribute £4M towards the stabilisation works as a condition of their £1.7B second government support grant.
• Engineering works: completion of pre-design survey work requires a further 4-month programme to inspect each upstream pedestal (the lower housings at each end of the suspension chain); the contractor is ready to proceed with the work on release of funding. See project funding statement above.
• Project Plan: LBHF report that they have provided the ‘robust project plan’ called for by the chairman. We would expect to see a review of alternative options including the replacement of the bridge with a modern structure, taking into account the cost and programme viability of restoring a bridge built over 130 years ago for a very different traffic type and density. 
• Temporary crossing (stage 1): ferry transport for pedestrians and cyclists has been investigated and can be operational within 66 days of contract commitment and release of funding.  See project funding statement above.
• Temporary crossing (stage 2): pedestrian and cycle use of the bridge can be resumed for a  limited period after installation of temporary stabilising frames over the pedestals.  Obtaining the necessary statutory planning consents and carrying out site construction would require around 7 months; estimated cost is £14M.  See project funding statement above.
• Project programme: overall period for completion of the works as currently foreseen, including measures to meet TfL increased traffic loading requirements, is estimated at approximately 6 years – from release of funding.

Bridge permanent stabilisation – cast iron pedestals – slide from meeting

We’re a little concerned that substantial time and costs are currently being allocated for shoring up the cast iron pedestals that are clearly a long way past their best:  4 months/£2.3M blast cleaning prior to 7 months investigation and temporary stabilisation/£13.9M, followed by 21 months/£32M permanent stabilisation, in addition to a planned temperature control system to lower the risk of further cracking.

Hammersmith Bridge closed: Motor traffic:10th April 2019; Completely:13th August 2020

After much media/social media coverage, including stories on London TV news, a task force was set up on 9 September, chaired by Baroness Vere (roads minister), which includes representatives of the local councils, TfL and Network Rail (for their experience of cast iron bridges), the Port of London Authority and GLA. The task force’s project director is Dana Skelley, a chartered civil engineer, formerly director of roads for London and responsible for the London-wide roads modernisation ahead of the London Olympics and the repairs to Hammersmith Flyover.

Completing the full repair of the Bridge is currently predicted to cost £141-£163m, with stabilisation just to allow safe pedestrian and river traffic at £46m, considerably more than first envisaged.  We covered the announcement of a temporary pedestrian/cycle bridge in April, which is believed to have been costed at less than £10m.  Before lockdown, planning was to be sought for this during the summer with construction starting this autumn, but this has not happened.  We followed up in June with our ideas about widening the pathways while work progresses elsewhere, making the bridge suitable for safe bidirectional cycling and walking; these are also clearly ideas yet to be considered given the new circumstances of complete closure.

Neither the Council nor TfL can finance costs at this level, so government support is essential. The possibility of tolls to finance the work has not been ruled out, indeed some are campaigning for this to make more funds available to speed up the work.

The disappearing Crossrail opening date

Construction projects still typically employ analogue leaders in a digital age

Mega transport projects are almost always fraught with delays and cost overruns because of the often inappropriate governance and leadership.  Inappropriate leadership – really ? Surely they’re run by Captains of Industry with huge experience and many letters after their names ?  But the leadership is most often bound up with the management of high budget, and perceived high risk items, such as tunnelling with Tunnel Boring Machines (TBM) – the so called “bricks and sticks” – often 80%+ of the initial budget.

Another day at the TBM office (here for the SuperSewer)

Appointments like these often address last century’s problems, a bit like taking over a British Leyland production line, only to discover that it’s now staffed by strike-free German-made robots, seemingly little delayed by the pandemic, at least here in Hammersmith. These elements are significantly lower risk than they once were, because of such mechanisation and associated technologies, engineered processes, resulting in tighter controls and more repeatability “at the coalface”, even though still beloved of TV documentaries with some false jeopardy added to spice them up.  Still, documentaries do serve a valuable purpose in illustrating the point – the operator at the controls of the TBM deep underground is using a computer keyboard, mouse, several screens, a desk phone, with not a shovel in sight.

To re-purpose a phrase from the last decade, these projects still typically employ analogue leaders in a digital age.  It’s commonly assumed that the “backroom boys” will sort of the hidden techie stuff – keep out of the detail.  WRONG!  This is where the risks are nowadays, in signalling and other heavily software-based systems, sometimes poorly designed code, frequent legacy issues, often clunky low-performance or de-facto interfaces (sometimes as simple as on/off dry contacts, AKA electromechanical relays, or their software equivalent “control points”), logical “gotchas” and subsequent system integration problems.

The issue is peculiarly amplified in railways, where proven operational safety is expected, yet a lot of what could provide that – 100% reuse of existing proven designs, robot style, ironically more akin to a modern tunnelling process – allowing the project to focus solely on what must be changed, is in this environment, swamped by commercial, time, perceived risk, or political pressures to use this supplier or that solution. This results in yet another bespoke railway with the inelegant compromises that Heath Robinson would recognise.  Amplifying the misconception that the project is some sort of smooth production-line shown in the plans, the term “production design” is regularly misused, whereas the earlier compromises mean the endeavour has unwittingly become a “prototype design” – the approach to building a unique prototype like Crossrail or HS2 vs. a production design for 1000, or 100,000 units a year are rather different – your scribe has done all three.

Future leaders should present their software engineering credentials at the door

Hammersmith Bridge underside and steelwork – May 2020

The Society’s committee is of the view that as part of the renovation work, there is a great opportunity to improve the Bridge to make it better suited to future needs, requiring more space for pedestrians and cyclists, as mentioned in our last article.  Our proposal is to widen the pathways to allow safe and satisfactory bidirectional walking on one side, and bidirectional cycling on the other, so that cyclists no longer need to compete with road traffic, significantly improving safety.  Currently, because of the somewhat narrow walkways, it’s not possible to safely cycle or even pass easily when walking, certainly not in a wheelchair or buggy.  We think this can be done both at modest cost (certainly compared with the 🔗Garden Bridge!) and largely independently of the planned repair works, so as not to lengthen the closure.  We have a brief update on repair works at the foot of this article.

The bridge’s narrow pathways for most of the span measure approximately 1.6m, widening at the pillars to approximately 1.8m, but still too narrow for bikes to pass safely (one of the reasons cyclists have to dismount currently), let alone to support social distancing needed now, and possibly in the future.  We’ve now looked at the structure in a little detail, and, as shown on the photos here, the pathways are supported by simple cantilevers, apparently bolted on.

Hammersmith Bridge – historical repairs (photo: Keepingthingslocal)

Steelwork underneath the bridge was repaired section by section in the 1970’s, and a new grid of substantial longitudinal girders replaced the originals (pierced where bridge hangers meet the deck). Historic photos (right) show the original, very much less substantial steelwork.  Given the scope of the repair works, and amount of money and time to be spent on repairs, there seems little reason not to now consider the attached pathways in more detail, especially if the planned temporary bridge removes the need to keep it open during the works.

Old Oak development area

Henry Peterson of the 🔗Old Oak Neighbourhood Forum and Grand Union Alliance – whose planning knowledge has been invaluable to local groups such as our affiliate 🔗St. Helens R.A. in the past – spotted that developers were seeking increases in height to approved planning permissions by means, not of a new planning application, but through a technical route using 🔗Sections 96A and 73 of the Town & Country Planning Act 1990 to seek minor material amendment approval, to “optimise” a planning consent. The amendments in question are often by no means minor and should warrant a new planning application.

This route has been used in a permission for North Kensington Gate (South) on Scrubs Lane where the developers have sought to increase the approved height of the development from 19 to 22 storeys, and the housing units by 20%. The Society and others have opposed the application as the planning context has dramatically changed from the original permission, where  intensive development was envisaged on that side of the area – now no longer part of the development plan following the exclusion of the Car Giant site – and with significant public transport additions planned via a new Overground station at Hythe Road – also no longer on the agenda, partly because of the many pressures on TfL finances.

TfL is planning a temporary footbridge parallel to Hammersmith Bridge at the request of H&F Council, to assure pedestrian and cycle transit throughout the repair programme.  The aim is to give over the entire Bridge space to the continuing works, with the result that the total closure time could be reduced by 9-12 months.

Hammersmith Temporary Bridge

In an online webinar on 3 April (replacing planned exhibitions which had to be cancelled), representatives of TfL and LBHF set out their scheme for a prefabricated steel structure supported by 2 piers in the riverbed, on the downriver side of Hammersmith bridge. It would be the same height as the Bridge and would have no impact on river traffic.   The usable deck would be 5.5m wide and there will be separation of cyclists and pedestrians (no motorbikes allowed).

Access would be via Queen Caroline Street on the Hammersmith side via gradual ramps. It would take 6-7 months to complete, and planning permission would stipulate it being in place for up to 5 years, with the aim of re-using the structure elsewhere afterwards.

Keeping foot and cycle traffic flowing has to be a welcome initiative. The one downside is that the structure would close the Thames Path on either side, meaning a detour – possibly via the rear of Riverside Studios or past the Apollo and round by Fulham Palace Road on the North side, and via Riverview Gardens on the Barnes side.

Meanwhile the pedestals, hangers, chain bearings and hanger connections are being worked on and acoustic monitoring of the Bridge structure continues. A detailed Scope of Works together with costs is expected later in the spring. The new deck will be steel, with resin on top, which will perform far better than the asphalt over boards which were alarmingly visible previously. The repairs will give 60 years of design life. 

Can we make the restored and repaired bridge work better in the future ?

Continued →