Air quality modelling for the Barbican Low Emissions Neighbourhood
The City of London Corporation received funding from the Mayor of London to implement a Low Emissions Neighbourhood in the Barbican, Guildhall and Barts area. One of the LEN proposals included options for restricting access to Beech Street, which runs underneath the Barbican, to all but the cleanest vehicles.
The CERC Consultancy team worked with WSP to quantify the air quality impact of a number of different physical and emissions-based access restrictions for Beech Street. WSP provided traffic data for Beech Street and the surrounding roads for each scenario, taking into account the potential rerouting of restricted vehicles onto the surrounding roads. CERC used ADMS-Urban to model the impact of the changes to traffic flows on concentrations of NO2 in the surrounding area.
Beech Street is a covered road, with some sections completely covered and some partially covered. The effects of this complex layout on the dispersion of pollutants and chemical reactions was taken into account using the ADMS-Urban Advanced Street Canyon and Tunnels options and a NOx-NO2 correlation derived from local monitoring data.
The maps show the modelled annual average NO2 concentration and the change in annual average NO2 concentrations with Beech Street restricted to Low Emissions Vehicles.