Piccadilly Underpass ventilation works

The Piccadilly Underpass and its ventilation system were originally constructed in 1962 as part of works to relieve traffic congestion. It takes two lanes of traffic in either direction under Hyde Park Corner between Piccadilly and Knightsbridge.

The ventilation fans inside the tunnel were designed for pollution control to help reduce pollution levels when they rise above certain trigger levels. These fans are now at the end of their service life.

We are working with FM Conway to replace them. Work will be completed in 2024. This work is necessary to comply to Health and Safety Regulations, the advanced works commenced from 10 July of 2023 to mid-December 2023.

During these works, only one lane of the underpass will be open to traffic in one direction, and there will be times when both lanes will be closed on weekends. Local traffic management plans and diversions will be in place to guide vehicles from one end of the closure to the other.

Please note that duration of the advanced works is subject to change if the site team encounter any unforeseen difficulties, such as engineering challenges or bad weather.

Please find below key dates for planned closures.

Single lane closures

• Eastbound tunnel closure 2 from 25 September 2023 to 26 November 2023
• Westbound tunnel closure 2 from 27 November 2023 to 18 December 2023

Weekend closures

Weekend closures run from Friday night to Monday early morning.

• 22 September 2023 to 25 September 2023
• 17 November 2023 to 20 November 2023
• 24 November 2023 to 27 November 2023
• 1 December 2023 to 4 December 2023
• 8 December 2023 to 11 December 2023

Please note that dates are subject to change if there are any unforeseen circumstances or engineering challenges that we encounter on-site.

This page will be further updated as the works progress.