LONG READ For eighteen months, the redesigned junction at Putney Bridge has been making daily life worse for tens of thousands of people. Buses queue from the river to the common. Drivers crawl through signal cycles. Pedestrians wait through multiple phases. Cyclists navigate a layout that satisfies nobody. The congestion bleeds into residential streets across SW15.
In that time, a lot of claims have been made about why this happened. Politicians blame Hammersmith Bridge. Officers say traffic volumes have risen. Campaign groups say the data proves their case. Residents hear different figures from different people and struggle to know what is true. Eighteen months is long enough for bad information to calcify into received wisdom, and long enough for the people responsible to hope that everyone simply gets used to it.
On Monday, Putney held its first hustings ahead of the council elections on 7 May. Candidates for our ward seats stood before residents and were asked to account for the junction. This election is the one mechanism residents have to force change: to replace the representatives who approved this scheme or who failed to scrutinise it, and to extract commitments from those who want their votes.
During that hustings, one resident – Cynthia – cut to the heart of it. She told the panel she had worked in the corporate world for years, and that when organisations make big changes, they do impact assessments. Had Labour done one? Had the Conservatives, whose officers began the scheme, done one that accounted for Hammersmith Bridge closing and for Covid? She called it “remarkable irresponsibility” to carry out a major change without a professional assessment of the consequences.
The cabinet member’s response
The Labour Cabinet Member for Transport, Jenny Yates, responded that three types of traffic modelling had been done and that TfL operates “a very lengthy and elaborate six-stage approval process.” There had, she said, been “a lengthy impact assessment.” The congestion, she explained, only became apparent after the scheme was built and TfL’s signal timings needed changing.
After the hustings, a reader named Diana wrote to us with the question that Cynthia’s challenge had left hanging: “Was the 2023 plan sign-off for the junction after a new feasibility study with the impact from Hammersmith Bridge closure?”
It is the right question. And the answer, drawn from every council paper, committee minute, FOI response and technical report we could obtain, is worse than either of them might have expected.
The junction redesign was modelled on traffic data collected during the pandemic. It assumed Hammersmith Bridge would reopen to motor vehicles by 2026, an assumption that proved false. TfL’s own signals team warned in writing that the scheme would cause “extensive queuing” and “significantly decrease” bus performance. And the “consultation” consisted of emails to 23 organisations, four of which replied. No leaflets. No public advertising. No social media.
The scheme was approved unanimously.
A key question about traffic volume
Diana is not alone in wanting answers. In the comments under our bridges investigation earlier this month, Richard Carter pointed out that traffic comparisons using 2020 as a baseline were “completely meaningless, since the 2020 figure was hugely depressed by the restrictions imposed by Covid.” Andrew Walmsley noted that “according to TfL’s own data, traffic across the combined Chiswick/Putney/Wandsworth/Kew/Hammersmith bridges is lower than before Hammersmith Bridge closed.”
Both are right. We promised in those comments to give the traffic data “a proper treatment rather than a line in a governance story.” This is that treatment: a single, clear account of what happened, what the numbers actually show, and what the documents prove. Every claim below is sourced to an official record. Where we have done calculations, we show our working. Where the evidence runs out, we say so.
Here is what the documents show:
- TfL’s own signals team warned in writing that the scheme would create “extensive queuing,” that queues would “completely fill Putney High Street and into Putney Hill,” and that bus performance would “significantly decrease.” The scheme was approved anyway.
- The council’s own approval paper admitted the design was “initially over capacity.” The proposed fix (relocating bus stops) had already been rejected by TfL Buses. The scheme was approved without the fix.
- The junction was modelled on four days of traffic data from July 2021, collected between lockdowns, when London was nowhere near normal operating conditions.
- The model assumed Hammersmith Bridge would reopen to motor vehicles by 2026. It is still closed. No confirmed reopening date exists.
- The “consultation” consisted of emails to 23 organisations. Four replied. No residents were consulted. No leaflets, no public advertising, no social media. A nearby public realm project in the same programme used leaflets and got 129 responses.
- The signal timings TfL programmed didn’t match the approved model. Putney Bridge Road lost 21 seconds of green time. The council says it was “late in clocking” the discrepancy. TfL says it holds no information about any review. Nobody has explained who changed the timings or why.
- Daily traffic across Putney Bridge is down, not up. Down 1.9% since 2018. Peak-hour volumes are essentially flat. Total five-bridge traffic is down 24.7%. The congestion is caused by the redesign reducing the road’s capacity to handle the vehicles that were always there.
- TfL holds minutes from an August 2023 RSPG meeting (one month before the scheme was approved) that have never been made public.
What follows is the evidence, document by document.
The feasibility question
The junction redesign was modelled using traffic data collected over four days between 15 and 18 July 2021. That is stated in Paper 25-398, the council’s own review document, at paragraph 13.
It was not the first attempt. Initial modelling had used data from October 2019, before the pandemic. As the paper explains: “The data used to model the new junction design was from July 2021. Initial modelling was done using data from October 2019. However, given the prolonged modelling process, TfL asked for revalidation of the data to ensure it remained relevant, hence July 21 data was obtained.”
July 2021 was not a normal month. England was between lockdowns. The government’s roadmap had lifted most legal restrictions on 19 July, the final day of data collection. Working-from-home rates were far above pre-pandemic levels. London-wide traffic in 2021 was substantially below its 2019 level.
More significantly, the modelling assumed Hammersmith Bridge would reopen to motor vehicles by 2026. Paper 25-398 is explicit about this at paragraph 14: “The standard London wide assumption for all modelling work at the time (2021) was that Hammersmith Bridge would be open in 2026, and that was what was agreed with TfL as the position with this project.”
Hammersmith Bridge has been closed to motor vehicles since 10 April 2019. It carried 25,869 vehicles per day in 2018. At the time of writing, in April 2026, it remains closed with no confirmed reopening date for motor traffic. The assumption was wrong.
TfL asked for more work. It is unclear whether it was done.
On 20 July 2022, TfL’s Road Space Performance Group (the body that reviews changes to London’s road network) considered the Putney junction scheme. The RSPG did not endorse it. Instead, it deferred, asking that “the scheme is assessed strategically in the wider area to help understand where traffic is coming from and why it’s traversing through Putney High St in the first place, with scenarios that include the closure of Hammersmith Bridge.”
That is a significant request. It called for exactly the kind of modelling that would test whether the design could cope without Hammersmith Bridge reopening.
Fifteen months later, when the scheme came before Wandsworth Council’s transport committee for approval in September 2023, Paper 23-304 stated at paragraph 10 that the RSPG’s “assessment and approval” had been obtained.
When committee members asked whether the closure of both Hammersmith and Wandsworth bridges had been factored into TfL’s modelling, the minutes record that officers responded that “modelling was done on a variety of scenarios and TfL would have factored scenarios for both the closure and opening of the bridges.”
Whether TfL actually produced the Hammersmith Bridge closure scenarios that the RSPG specifically requested in July 2022 is a question the documentary record does not resolve. What we do know, from an FOI response (FOI-3128-2526), is that TfL holds minutes from an August 2023 RSPG meeting (one month before the scheme was approved) that have never been publicly disclosed. TfL noted: “We do hold additional minutes from August 2023 and these could be provided if requested.”
We will be requesting them.
The warnings that were ignored
Before the junction scheme reached the committee, TfL’s own signals team provided written feedback. That feedback, preserved in Appendix C to Paper 22-331, is the most damning document in the entire record.
TfL warned that “the numbers coming out of the modelling to date show the proposals will create a lot of congestion which will have a negative impact on the bus network and cause extensive queuing.”
The warning was specific. Some vehicle movements would receive “around 75% less green time.” The northbound queue would “completely fill Putney High Street and into Putney Hill during the morning peak.” Bus performance would “significantly decrease.” The scheme would worsen air quality by undermining TfL’s existing strategy for the area.
Every one of those predictions came true.
The council’s own paper admitted the design was over capacity
Paper 23-304, the document that went to committee in September 2023, contained an extraordinary admission at paragraph 15: “Although initially over capacity the current concept, with staggered crossings, was thought to be within reach of acceptable performance with mitigations to aid bus journey times.”
Read that sentence carefully. The council’s own approval paper acknowledged the design was “initially over capacity.” The path to acceptable performance depended on mitigations, specifically relocating bus stops to reduce junction blocking.
Paragraph 14 of the same paper records what happened to those mitigations: “Bus stop relocations were proposed to reduce congestion, junction exit blocking and to improve network performance in an attempt to offset any impacts of the junction proposals however these mitigations were rejected by TfL Buses.”
The design was over capacity. The proposed fix was rejected. The scheme was approved anyway.
The funding pressure
Why proceed with a scheme that TfL’s own engineers had warned against and whose mitigations had been rejected? The documentary record points to one answer: money.
Paper 22-331 records that the council had secured Future High Street Fund money for the Putney scheme, with an expenditure deadline of March 2024 and £344,732 at risk of being lost if the project did not proceed. Minutes from a November 2022 stakeholder meeting (obtained under FOI 10409) state plainly that “24 March is funding deadline.”
A July 2022 stakeholder meeting had warned that revisiting the design would “lead to loss of Future High Street Funding.”
The committee approved the scheme unanimously on 21 September 2023. Cllr John Locker, who as Cabinet Member had presented earlier versions of the scheme, was absent from the vote. He sent his apologies.
The consultation that wasn’t
Under FOI reference WBC-FOI-11520, Wandsworth Council disclosed the full extent of the public consultation for the junction redesign.
The council emailed 23 organisations. Four responded. There was no public advertising. No leaflets. No social media outreach.
For context, the Watermans Green element of the same wider project, a comparatively modest public realm improvement nearby, used leaflets and received 129 responses, as recorded in the November 2022 stakeholder meeting minutes.
The junction redesign, which would reshape the most important traffic intersection in Putney, received responses from 17% of the organisations that were contacted and from precisely zero members of the public. Nobody who drives through the junction, walks across it, waits for a bus at it, or cycles through it was asked.
One of the four consultation responses that was received came from TfL itself, which noted the need to spend the budget by the March 2024 deadline.
What the traffic numbers actually show
Traffic data has been weaponised by every side of the Putney Bridge and Hammersmith Bridge debate. Here is what the official figures say, with sources.
The five-bridge picture
Paper 25-398 contains a table showing average daily traffic across five Thames crossings: Chiswick, Kew, Hammersmith, Putney and Wandsworth bridges.
| Measure | Vehicles per day |
|---|---|
| Five-bridge total (2018) | 187,429 |
| Five-bridge total (2024) | 141,147 |
| Change | -46,282 (-24.7%) |
| Hammersmith Bridge before closure (2018) | 25,869 |
That drop of 46,282 vehicles is nearly twice the 25,869 vehicles per day that Hammersmith Bridge carried before it closed. In other words, even accounting for every vehicle that used to cross Hammersmith Bridge, traffic across the five crossings has still fallen significantly. Some of Hammersmith Bridge’s traffic redistributed to other bridges. Much of it simply disappeared, through mode shift, route changes, or reduced travel.
Andrew Walmsley’s observation in the comments was correct: total cross-river traffic in this corridor is lower than before Hammersmith Bridge closed.
Putney Bridge specifically
| Source | Before | 2024 | Change |
|---|---|---|---|
| Paper 25-398 | 37,951 (2018) | 37,245 | -1.9% |
| DfT annual count | 42,498 (2019) | 37,313 | -12.2% |
The two sources use different methodologies, but both show the same direction: down, not up.
Richard Carter’s point in the comments was also correct: anyone citing increases over 2020 figures is using a baseline depressed by Covid restrictions, which renders the comparison meaningless. London-wide traffic in 2024 was 19.4 billion vehicle miles, still 4.4% below its 2019 level.
Peak hours: the measure that matters for congestion
Daily totals do not tell you about congestion. A road can carry fewer vehicles per day and still be gridlocked at 8am if those vehicles arrive in a compressed peak. The peak hour data from Paper 25-398 is therefore the most relevant measure:
| Peak period | Oct 2019 | July 2021 | June 2025 | Change (2019–2025) |
|---|---|---|---|---|
| Morning (AM) | 2,977 | 2,967 | 3,077 | +3.4% |
| Evening (PM) | 2,908 | 2,850 | 2,895 | -0.4% |
The morning increase of 3.4% is modest, and likely within normal variation. The evening peak is essentially flat.
The traffic volume through the junction during peak hours has barely changed. The congestion that Putney experiences daily is not caused by a surge of vehicles. It is caused by the junction redesign reducing the road’s capacity to process the vehicles that were always there, exactly as TfL’s signals team predicted.
The signal timing problem
If the junction design was flawed but at least modelled, the implementation introduced a further problem. The signal timings that TfL actually programmed into the traffic lights did not match those in AECOM’s approved model.
The AECOM post-implementation study and Paper 25-398 document the discrepancy. Putney Bridge Road lost 21 seconds of green time in the morning peak compared to the model. The Lower Richmond Road left turn lost approximately 10 seconds.
In November 2025, council officer Henry Cheung told the transport committee: “TfL hasn’t implemented anywhere near close to the approved model… we were late in clocking that TfL hasn’t implemented the approved model while it’s so far out.”
When Putney.news asked TfL to explain the discrepancy, TfL responded: “It is not uncommon for network conditions to evolve or for developments and schemes to influence how flows pass through an area.”
When we asked, via FOI (reference FOI-3129-2526), whether TfL had conducted any internal review of the signal discrepancy, TfL’s response was: “We do not hold this information, please contact the Borough directly for this information.” The council, in turn, has not disclosed any review.
TfL did confirm, in the same FOI response, that it had identified 25 complaints about the junction.
Nobody investigated what went wrong. Nobody has explained who decided to deviate from the approved model, or why.
What we still don’t know
The documentary record answers many of the questions readers have asked. But it leaves several gaps that we will continue to pursue:
The August 2023 RSPG minutes. TfL has confirmed these exist. They cover a meeting held one month before the committee approved the scheme. They have never been publicly disclosed. We are filing a targeted FOI request.
The Hammersmith Bridge closure scenarios. The RSPG specifically requested modelling with scenarios that included the bridge remaining closed. Whether this modelling was completed, and what it showed, is not clear from the documents disclosed so far.
The signal timing accountability. Who decided to deviate from the approved model? When? The council says it was “late in clocking” the discrepancy. TfL says it holds no information about any review. There is an accountability gap between the two organisations that neither appears willing to close.
The 300 vehicles-per-hour threshold. The council has used a figure of 300 vehicles per hour as a threshold for traffic interventions. When we asked, via FOI (reference WBC-FOI-11533), for the methodology behind this figure, the council’s response was: “information not held.”
The independent review. Paper 25-398 names two reviews: the AECOM post-implementation study (published as Appendix 1) and a separate report by Red Wilson Associates, “a specialised consultancy firm” commissioned in June 2025 “to identify changes that can be made to improve the operation of the junction.” The Red Wilson report has never been published. It does not appear on the council’s junction updates page. No summary of its findings has been made available. In addition, no review of the systemic failures has been conducted by either authority: not the data choices, not the ignored warnings, not the hollow consultation, not the signal discrepancy, not the accountability gap.
TfL confirmed in FOI-3129-2526 that it holds no internal reviews, investigations, or lessons-learned exercises. The council has not announced any equivalent. The junction is being fixed operationally. Nobody is investigating what went wrong institutionally.
What readers can do
All of the documents cited in this article are publicly available through Wandsworth Council’s democracy portal and TfL’s FOI disclosure process. Readers can submit their own FOI requests.
Transport Committee meetings are public. Residents can attend and exercise their right to depute, to address the committee directly.
The council committed to publishing residential street traffic data by 31 January 2026. Readers can check whether that data has appeared at the council’s junction page.
This story is not over. We will continue to follow the evidence.
This article draws on 19 source documents including council papers, committee minutes, FOI responses, technical reports, and TfL correspondence. A full source index is maintained by Putney.news.
I am not even sure I understand the motivation for the change. Assume the usual safety worries etc. just beggars belief that a junction, which fundamentally is the same (no new roads entering etc.) can be made worse.