New signs have been installed on the approach to Tower Bridge encouraging drivers to switch off their engines whilst waiting for the bridge to lift for a passing river vessel.
Three years ago Boris Johnson awarded £100,000 to Southwark and Tower Hamlets councils for a project to improve air quality near Tower Bridge.
Tower Bridge is raised around 900 times a year, delaying some of the 31,000 vehicles crossing the bridge each day.
Now signs have been installed to let drivers know when they can expect a long wait to cross the river and asking them to switch off their engines whilst they are queueing on the approaches to Tower Bridge.
Southwark Council has installed an air pollution monitoring station to measure the impact of the Tower Bridge anti-idling project and the authority hopes local residents will benefit from less polluted roads around the bridge.
Cllr Barrie Hargrove, Southwark's cabinet member for parks, public health and leisure, said: "The anti-idling scheme is a good example of joint working and it would be great to see more support coming through for local projects.
"I hope this scheme raises awareness about the damaging effects of idling with your engine on and encourages drivers across the capital to think carefully about ways they could help reduce air pollution."