London Under Water

With 200,000 properties in London at risk of flooding, the London Assembly is urging the Mayor to increase communication with Londoners to improve preparedness for flooding in the city.

The London Assembly Environment Committee have published a report outlining the steps the Mayor should take to reduce the risk of flooding and increase Londoner’s preparedness for flooding, with the increasing threat posed by climate change.

The Committee held meetings in September and December 2021 following severe surface water flooding in London in July 2021, with the Met Office reporting at the time that, on 12 July 2021, some areas of London, including Kensington, Westminster and Hammersmith, received almost 80mm of rain during the day, which accounted for approximately 170 per cent of average rainfall in July ^[1]. It followed up on progress so far at a meeting in December 2022 with the Deputy Mayor for Environment and Energy.

The Committee is urging the Mayor to consider the five recommendations in the report, including:

• Through London Resilience, the Mayor should annually bring together key partners including the Environment Agency and relevant Government ministries, the GLA, local authorities, Thames Water, Affinity Water, Transport for London, the Maritime and Coastguard Agency, and the London Fire Brigade to reassess and re-evaluate London’s preparedness for future surface water flooding events and the level of risk attached to flood events.
• The Committee welcomes the Mayor’s communication on flood risks to Londoners living in basements. However, the Mayor should further expand his communication to raise awareness among Londoners of flood risk and what actions they can take.
• The Mayor should focus some of his flooding communications on explaining the flooding-related consequences of Londoners paving over or replacing their green space with artificial grass. The Mayor, along with Councils, should promote the opportunity for Londoners to help prevent flooding in London by retaining and improving their green space.
• Following the completed London Strategic SuDS Pilot Study, the Mayor should regularly review the Urban Greening LPG with regard to SuDS and strengthen it as necessary, in light of the developing Climate Emergency; The Mayor should work with Thames Water and other partners to ensure the £1 billion investment needed in SuDS infrastructure is quickly in place for high priority locations. In response to this report, the Mayor should also provide an update to the Committee on progress following the London Strategic SuDS Pilot Study, including what additional investment has been secured and spent so far.