A man in his 20s died when a tree fell onto his moving car at the junction of Dollis Road and Abercorn Road in Mill Hill on Sunday 25 October, as Storm Boelo brought another weekend of strong winds and heavy rain to the UK.
The Metropolitan Police were called at about 12.40pm. Ambulance crews, incident response officers, hazardous area response paramedics and a trauma team from London's Air Ambulance attended, but the driver was pronounced dead at the scene. Police said they will work with the local authority and coroner to establish the circumstances.
Later that afternoon, two people were taken to hospital after scaffolding collapsed onto Streatham High Road in south London. The two events were different, and the investigations around them are different, but together they put one part of storm resilience directly onto London's streets: the condition, design and maintenance of the assets that sit beside the public.
Illustration of storm damage on a London residential street following severe winds. Illustration: London Construction Magazine.
London was outside the worst of Storm Boelo
London did not experience the highest winds recorded during Storm Boelo. The Met Office warnings concentrated the strongest wind risk across Scotland, Northern Ireland and northern England, where gusts of 60 to 70mph were expected widely and around 80mph was possible in exposed places.
London sat outside the amber wind-warning area. That makes the Mill Hill death particularly sobering from an asset-management point of view. A public tree does not need an 80mph gust to become dangerous if its condition, root stability, surrounding ground or exposure leaves it vulnerable. Police have not given a cause for the tree failure, so those questions now sit with the local authority and coroner.
The Met Office had specifically warned that Storm Boelo could bring down large branches and trees, damage buildings and create danger from flying debris. It also advised people to avoid walking or sheltering close to trees and buildings during strong winds.
Scaffolding came down on Streatham High Road
At about 1.30pm, scaffolding collapsed onto Streatham High Road. Two people were trapped beneath the fallen structure before firefighters arrived and were taken to hospital by London Ambulance Service. Their injuries were reported as non-serious.
Photographs from the scene showed scaffold tubes, boards and sheeting spread across the carriageway. Engineers were called to secure the remaining scaffold while the road was closed in both directions.
Firefighters at the scene reportedly referred to a strong gust bringing material down, although a formal cause for the collapse had not been established when the incident was first reported.
For construction, this is where wind stops being a weather forecast and becomes a design and inspection issue. Scaffolding, hoardings, temporary roofs, edge protection and tower cranes all carry wind loads, and those loads depend on the structure actually standing on site.
Sheeting can completely change a scaffold's wind load
A scaffold that is open to the wind behaves very differently once debris netting, temporary sheeting or advertising is attached. Those additions increase the surface area exposed to wind and can materially increase the loads transferred through ties, standards, base plates and the supporting structure or ground.
LCM's guide to scaffold pre-erection temporary works checks sets out why the design brief must describe the scaffold that will actually be erected. Ties, foundations, loading bays, hoists, sheeting, temporary roofs and later alterations all have to remain consistent with the assumptions used by the designer.
A scaffold can therefore start with a compliant design and later move outside that design if attachments are added, ties are removed for façade work or the configuration changes without review.
That is also why post-storm inspections are important. LCM's pre-storm guidance for Austen and Boelo identified scaffolds, hoardings, cranes and other temporary works as assets that should be checked against their design assumptions before severe weather and inspected again where conditions may have affected their safety.
The Work at Height Regulations require work equipment exposed to conditions capable of causing deterioration to be inspected after exceptional circumstances liable to jeopardise its safety. Wind loading is therefore not only a calculation completed when the scaffold is designed; the condition of the structure has to be managed while it remains on site.
The public realm is part of construction resilience
Storm resilience is often discussed through large engineering programmes: flood walls, drainage upgrades, reinforced embankments, reservoirs, electricity networks and coastal defences. Those projects are necessary, but a person's exposure to severe weather can be decided by something much closer to the pavement.
Street trees, scaffolds, hoardings, roofs, temporary structures, drainage gullies, retaining structures and roadside assets all occupy the boundary between engineered space and public movement. Their inspection and maintenance usually sit with different organisations, budgets and regulatory systems, yet failure occurs in the same physical space used by pedestrians, drivers and public transport.
That distinction was visible elsewhere in London during Storm Boelo. Highgate Woods was closed because of the wind risk, while London's Diwali celebration in Trafalgar Square was cancelled after health and safety advice concluded that conditions made construction of the temporary event infrastructure unsafe.
Those were preventative decisions. The asset was removed from use before people were exposed to it. For construction and public-realm management, that is one of the simplest forms of resilience available.
Billions are being spent on resilience, but inspection happens locally
The UK is already moving large amounts of construction spending towards climate adaptation. LCM's analysis of the climate resilience construction market identified £1.4bn of flood investment in England for 2026/27, about £2.6bn of Network Rail weather-resilience spending through Control Period 7 and a wider Climate Change Committee estimate that around £11bn a year of public and private adaptation investment will eventually be needed.
Those programmes fund major physical interventions: drainage, earthworks, flood barriers, coastal structures, asset renewal and monitoring. They cannot replace routine inspection of the individual tree, scaffold, hoarding or temporary structure sitting beside a road.
The engineering response to more frequent severe-weather events therefore has two scales. One is measured in billions of pounds and national infrastructure programmes. The other can be a visual inspection, a missing scaffold tie, a tree survey, a blocked gully or a decision to close an area before conditions deteriorate.
Neither requires waiting for record-breaking weather. The Met Office's highest Storm Boelo gusts were recorded hundreds of miles from London, yet a man died beneath a fallen tree in Mill Hill and two people were taken to hospital after scaffolding collapsed in Streatham.
At Mill Hill, the Metropolitan Police said it will now work with the local authority and coroner to establish the circumstances surrounding the fatal tree fall. In Streatham, engineers were called to secure the remaining scaffold before the High Road could return to normal use.
Expert Verification & Authorship
Founder & Author, London Construction Magazine | Construction Testing & Investigation Specialist