Charge home owners who concrete over gardens, Sadiq Khan report suggests
Households that pave over their gardens to build driveways should face extra charges because they contribute to urban flooding, a report commissioned by Sadiq Khan has suggested.
The London Climate Resilience Review has warned that paved gardens “pose a lethal risk to Londoners” by increasing surface water flooding.
It recommends that the Government consider introducing stormwater charges based on the amount of non-porous paved surface in a garden.
Mr Khan, the London Mayor, said he would work with the Labour Government to take forward the recommendations in the report.
Porous surfacing that allows rainwater to drain away has decreased by nearly 10 per cent across London since 2001, as more households choose to pave over their gardens to create driveways.
The increase has come as more councils have imposed charges for residents to park their cars on the street, particularly in the capital.
The recent rise in the use of electric cars, which has been supported by the Government and the London Mayor, also encourages off-street parking, as on-street chargers are more expensive and not readily available.
About 60 per cent of all properties that are at risk from flooding also face a threat from surface water runoff.
In July 2021, parts of London received more than twice the average July rainfall in two hours, leaving 2,000 homes flooded with stormwater and sewage. It also affected 30 Tube stations.
Last year, Philip Duffy, the chief executive of the Environment Agency, said surface water flooding “genuinely keeps me awake at night” and highlighted the death of a couple in their 70s stuck in floodwaters in Liverpool.
“There is a very, very clear link between the amount of hard surfaces that we now have across London, and an increase in surface water flooding,” said Emma Howard-Boyd, the former head of the Environment Agency, who led the review.
“Water has to go somewhere, and what we need to see is greater sponginess.”
The report cites the example of Melbourne in Australia, where households are charged a waterways and drainage fee to help manage flood risk, and have a payment added to water bills to offset the impact of stormwater.
In 2008, the UK government forced households to seek planning permission for non-porous hard surfacing of more than 54 sq ft but the Greater London Authority has said the guidelines are poorly enforced.
Risk ‘poorly understood’
Ms Howard-Boyd said the risk from paved gardens to homeowners and particularly to their neighbours was poorly understood.
“We would encourage people to look at and understand the knock-on consequences if we’re all doing a little bit of this work to gardens,” she said.
Other recommendations from the review, which began in June 2023, include encouraging the installation of systems that reuse shower water to flush toilets and water meters to help people cut down on usage as the capital faces the threat of drought.
The report warned that climate change could affect London’s GDP by 2-3 per cent every year by the 2050s, and that 43 per cent of London properties are likely to be affected by subsidence by 2030.
Mr Khan said: “I welcome this review, which I commissioned after seeing first-hand during recent years how extreme weather can devastate communities, ruin businesses and end lives.
“I accept the recommendations made to City Hall, and we will work to take forward the recommendations over the coming months, working with our new national Government, local councils, businesses and London’s communities. We do not have a moment to waste.”