One of the primary aims of the Mayor of London/TfL Streetspace interim guidance for boroughs is
accelerating delivery of low traffic neighbourhoods and school streets by working with boroughs to reduce through traffic on residential streets, to further enable more people to walk and cycle safely as part of their daily routine (p 4, emphasis ours)
The guidance is here: Mayor of London, TfL - Streetspace Guidance
You can suggest emergency Covid-19 measures for Southwark and agree with other suggestions here: Southwark Streetspace Commonplace map
Air Quality News, April 2020 - Scientists link England coronavirus deaths with exposure to toxic air
During lockdown air quality improved and walking and cycling increased following the decrease in traffic:
The Guardian, April 2020 - 'It's positively alpine!': Disbelief in big cities as air pollution falls
Unless emergency measures are implemented to ensure people can walk and cycle safely while maintaining physical distance, traffic and air pollution will increase as lockdown eases: