The Garden Bridge is a proposed public bridge over the River Thames in London. Designed by Thomas Heatherwick, and to be delivered by Arup, the concept is for a footbridge featuring trees and other vegetation. The project has proved very controversial for several reasons, including escalating costs, the tender proces, protection of existing views, the commercialisation of public space and the need for a new bridge at all.
The idea of a ‘floating paradise’ garden bridge was first raised by the actress Joanna Lumley in the late-1990s. The idea did not gain any momentum until 2012 when she began to approach Transport for London (TfL) and the then-Mayor of London Boris Johnson, who was keen to find a ‘legacy project’.
The draft business plan by the Garden Bridge Trust suggested the bridge would be open to the public 18 hours a day, but would close for private events on 12 days of each year, and on every summer weekend the rooftop of the landing podium would be rented out for commercial purposes.
A full planning application was submitted in May 2014. The aim was for construction to begin in 2015 and to be complete by 2018, subject to receiving planning permission and raising the required funds. Lambeth and Westminster City Councils conditionally approved the application in late-2014, followed by Johnson’s official approval.
In October 2016, the cost of the bridge was estimated to be £185 million. This included £125m of private money (including charitable gift aid) and £60m of public money, of which £30m was from TfL (£20m of this is to be repaid over 55 years), and £30m from the Department for Transport.
The bridge will be 367 m (1,204 ft) long and cross the Thames between Waterloo Bridge (200 m to the west) and Blackfriars Bridge (300 m to the east). It will project from the roof of Temple tube station on the north bank to Queen’s Walk on the Southbank area, currently a public open space.
The structure will be made from concrete, steel and cupronickel (a composite of copper and nickel). The warm colour of the cladding is intended to provide a contrast to the steel and concrete structures on both sides of the river.
The bridge will be planted with 270 immature trees as well as shrubs and wildflowers. The south end will include plants such as willow, birch, violet and primrose; while the north end will include wisteria, roses, irises and summer snowflakes. To limit structural wind loading, the trees will be maintained so as not to exceed heights of 15 m at bridge piers and 2 m near the bridge landings.
The project has been beset by numerous controversies since 2012. In an attempt to try and counter some of these issues, the Garden Bridge Trust has provided a 'Mythbuster' on its official site.
The most prominent concerns are:
Attention has been focused on a business trip to San Francisco that the then-Mayor of London Boris Johnson with his chief-of-staff and deputy Mayor for Transport in February 2013. This trip, listed as private, was intended to promote sponsorship opportunities for the bridge. The designer Thomas Heatherwick was also invited to attend the meeting to discuss his design concept, despite TfL having not at this time formally invited design bids.
There was also concern over the fact that Heatherwick’s design was selected by one official, as opposed to the panel required for major infrastructure projects. The President of the RIBA Jane Duncan, requested the project be put on hold pending an investigation into the tendering process.
In September 2015, Lambeth Council suspended their negotiations with the Garden Bridge Trust over the terms of the lease, which would be required at the Southbank end of the bridge. Necessary lease modifications were reported as having been put in place by March 2016.
The housing trust which holds the long-term lease over the southern landing section, Coin Street Community Builders, have delayed giving permission. However, in response to anti-bridge campaigners, they have indicated that it is not in a position to oppose elected governments’ decisions.
It has also emerged that due to Johnson’s desire for urgency in starting work, contingency plans were created to turn the bridge into a pier if the necessary permissions for the southern bank were not given.
 Rules and restrictions
There has also been consternation over the ‘draconian’ rules and restrictions that have been proposed by the business plan. In November 2015, planning documents showed that there would be heavily-controlled public access, with visitors’ phone signals tracked to alleviate overcrowding. In addition, there would be a video surveillance system and security staff with limited police powers that would give them the right to issue on-the-spot fines.
The bridge rules were stated as prohibiting: ‘Any exercise other than jogging, playing a musical instrument, taking part in a 'gathering of any kind', giving a speech or address, scattering ashes, releasing a balloon and flying a kite.’
When first promoted, the Garden Bridge Trust claimed that private sources would be sufficient to finance the £60m project. However, a total of £60m towards the capital cost was committed from public funds, with £30m pledged from TfL funds by Johnson, and £30m pledged by HM Treasury.
In the meantime, the proposed cost of the bridge had, by August 2015, escalated to £185m. Officials began raising concerns, with contrasts made between the cost and the Millennium Bridge which had been built for just £22m.
In July 2016, the new Mayor of London Sadiq Khan, who had claimed while campaigning that he would scrap the project, said that no more public money would be spent, and that preparatory work had been halted for City Hall to review the financial situation.
Having taken office at City Hall in 2016, Sadiq Khan announced that the bridge was ‘too expensive to cancel’, with almost £40m spent without any on-site construction work having begun.
Khan said; "If we were to cancel the project today … [the costs] would have been spent for no benefit at all for Londoners. However, if we complete the Garden Bridge, then not only will TfL be paid the £20m loan by the Garden Bridge Trust, but they will also pay roughly £22m in VAT to the government. That would leave an ultimate cost to the taxpayer of £18m for completing the Garden Bridge, significantly lower than the £37.7m cost of cancelling it... It is clearly in the interest of taxpayers to complete the Garden Bridge."
 September 2016
Khan announced a formal review into the project’s value for money to be led by Dame Margaret Hodge, saying' "I’m clear that since the beginning of the project there hasn’t been the necessary standard of transparency and openness around the Garden Bridge".
 October 2016
In October 2016, the National Audit Office (NAO) published the results of its inquiries into the £30m funding provided by the Department for Transport. It concluded that the Department had committed the funding despite assessing the original business case as having a significant risk of representing poor value for money. Providing the funding in a block grant to TfL left the Department with limited oversight of its own support to the Garden Bridge Trust.
 January 2017
The Garden Bridge Trust's annual accounts showed a shortfall of £56m, leading them to state that they were "unable to conclude [the bridge] is a going concern".
Despite this, the trustees still expected construction to start in 2017 - necessary as the planning consents expire in December - the Trust needs to raise an extra £56m from donors. This is money that can be spent by the Trust immediately, and so poses a risk for donors if the project is eventually cancelled. The Trust has stated that any additional funding would not be repayable "if the project is not able to proceed" in the first half of 2017.
Despite Sadiq Khan pledging that no more taxpayers' money would be allocated to the project, nearly £40m stands to be lost if the project is cancelled.
 February 2017
The Garden Bridge Trust was cleared of financial irregularities by the Charity Commission, although it found that trustees could make improvements to their annual reporting.
David Holdsworth, Charity Commission CEO, said; “We have been able to offer public assurance that the Garden Bridge Trust is meeting its obligations as a registered charity and that it has the proper financial controls in place. We are aware of the considerable public debate regarding this project. Our role is not to comment on the merits of the project but to assess concerns about its governance and ensure it is compliant with the legal framework for charities.”
 April 2017
Dame Margaret Hodge, who was commissioned by Sadiq Khan to investigate the project, published her review in which she called for the project to be scrapped.
She wrote that:
"Value for money for the taxpayer has not been secured. It would be better for the taxpayer to accept the financial loss of cancelling the project than to risk the potential uncertain additional costs to the public purse if the project proceeds.
"In the present climate, with continuing pressures on public spending, it is difficult to justify further public investment in the Garden Bridge.
"I would urge the Mayor not to sign any guarantees until it is confirmed that the private capital and revenue monies have been secured by the Garden Bridge Trust."
Her report also found:
- The Trust has lost two major private donors and has had no new pledges since August 2016.
- Very little progress has been made on raising money to fund maintenance of the completed bridge.
- There was not an open, fair and competitive process for two of the procurements so far undertaken.
The Garden Bridge Trust responded in a letter to Hodge, rejecting her cirticisms. The Trust Chairman, Labour Peer Mervyn Davies said; “over three quarters of Londoners support the bridge being built” and suggested to her that her conclusion that the bridge should be scrapped was “based almost entirely on your own opinion and the word of others who have expressed a view, rather than on the word of those with technical expertise in this field”.
 Sadiq Khan withdraws support
On 28 April 2017, Sadiq Khan announced that he was withdrawing his support for the project, refusing to provide the vital financial guarantees needed for construction to begin. Khan said he had taken the decision because of a continuing shortfall in fundraising for the scheme, and a lack of the necessary land use agreements despite three years of talks.
“The funding gap is now at over £70m and it appears unlikely that the trust will succeed in raising the private funds required for the project. I am simply not prepared to risk a situation where the taxpayer has to step in and contribute significant additional amounts to ensure the project is completed.”
Although the Mayor does not have the power to scrap the project entirely, his withdrawal of the public guarantees effectively brings the long and sorry story of the Garden Bridge to an end.
 Project cancelled
On 14 August 2017, the Garden Bridge Trust announced closure of the project. This followed the letter from Sadiq Khan on 28 April stating that he was not prepared to sign the guarantee for the annual maintenance costs of the Bridge, a condition of the planning consent.
Lord Mervyn Davies, Chairman of the Garden Bridge Trust wrote to Sadiq Khan saying:
"It is with great regret that Trustees have concluded that without Mayoral support the project cannot be delivered. We are incredibly sad that we have not been able to make the dream of the Garden Bridge a reality and that the Mayor does not feel able to continue with the support he initially gave us. We had made great progress obtaining planning permission, satisfying most of our planning conditions and we had raised £70m of private money towards the project.
"The Garden Bridge would have been a unique place; a beautiful new green space in the heart of London, free to use and open to all, showcasing the best of British talent and innovation. It is all the more disappointing because the Trust was set up at the request of TfL, the organisation headed up by the Mayor, to deliver the project. It is a sad day for London because it is sending out a message to the world that we can no longer deliver such exciting projects."
The Trust will be wound up and contracts terminated.
 Related articles on Designing Buildings Wiki
- Bridge construction.
- Bridges of the world.
- Constraints on construction projects.
- Garden Bridge - alternate design.
- Landscape urbanism.
- Pier 55, New York.
- Skygarden, Seoul.
- TfL’s Thames crossing plans.
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