Blackwall Tunnel closures have been linked to increased congestion and a threefold rise in dangerous driving on roads in the capital.
Geotab analysed the data of more than 16,000 commercial vehicles in 2024, revealing the significant impact of Blackwall Tunnel closures on safety, congestion and travel disruption.
Dangerous driving incidents surged by 231% on Tower Bridge during tunnel closures, with lorries seeing a 341% increase in harsh braking events.
Over 5,500 commercial journeys were rerouted, resulting in an additional 91,000 miles driven on alternative central London routes in 2024.
Meanwhile, alternative routes through central London saw a 43% rise in travel times, reflecting a slowdown in traffic alongside higher fuel consumption and emissions
The report also raises concerns about the forthcoming opening of the Silvertown Tunnel, cautioning that tolls could worsen traffic displacement, congestion and safety risks.
The Blackwall Tunnel is undergoing closures to support the construction of the new tunnel, aimed at reducing journey times and to help manage air pollution in south-east London. There are concerns, however, that new toll charges for using both Blackwall and Silvertown Tunnels will increase traffic on alternative routes, intensifying congestion and safety concerns in those areas.
The Geotab study bears this out, with travel time on East Smithfield, for example, increasing by 43%. The Blackwall closures in combination with restrictions on the Rotherhithe Tunnel redirected more vehicles toward Tower Bridge, intensifying its usage. The average daily vehicle count on Tower Bridge increased by 18%, with dangerous driving incidents increasing by 231%, and lorries experiencing a 341% rise in harsh braking events – potentially impacting pedestrian safety.
“Our data shows that the Blackwall Tunnel closures have had a negative impact on traffic flow and safety in other areas,” said Aaron Jarvis, associate vice president, sales and business development, EMEA, Geotab.
“We cannot say now whether the introduction of a toll to the Blackwall Tunnel for the first time since it opened in 1890 will continue the displacement of road traffic to these other areas, but we do know that commercial vehicles spending more time on the road going shorter distances is not good for local communities, the economy, air pollution, or driver well-being.”
Geotab’s recent mental health survey highlighted the impact of driver stress with 90% of lorry and van drivers saying work-related stress negatively impacts their driving. For many, congestion heightens concerns about job performance, safety, and overall wellbeing.
“These disruptions add significant challenges for commercial drivers who are under constant pressure to meet delivery schedules. The additional time spent in congestion not only increases operational costs but also contributes to increased driver stress, as they navigate unpredictable travel conditions,” Jarvis added.
