Mayor Boris Johnson has launched his “radical” sustainable drainage action plan to avert flooding and overflowing sewers in London, with rain gardens, green roofs and other SUDS measures high on the agenda. The draft London Sustainable Drainage Action Plan, which is open for consultation for three months, aims to avert the risk of major flooding which London is likely to face by 2050 thanks to sewers which are approaching the limits of capacity.
This announcement comes on the same day that the National Policy for the Built Environment Committee, a House of Lords Select Committee, received oral statements in relation to the development and implementation of national policy for the built environment. The Committee was given a reporting deadline of 23 March 2016 with a deadline for submissions is 6 October 2015. Witnesses included Noel Farrer, President, Landscape Institute and Iain Taylor, Director of Business Development, Land Trust plus testaments from Town and Country Planning Association and the Campaign to Protect Rural England. Farrer spoke on the importance of green infrastructure in planning and design, not only in parks but as a crucial component of every part of a city.
Noel Farrer, President of the Landscape Institute, presenting evidence to the National Policy for the Built Environment Committee – Lords Select Committee – click on image above to listen to the presentation.
The Mayor Boris Johnson, in partnership with Thames Water, the Environment Agency and London Councils today published the first London Sustainable Drainage Action Plan for consultation, identifying potential flooding hotspots across the city and proposing innovative ways of diverting rain back from the sewers into the soil with rain gardens or green roofs. A flooding ‘heat map’ published today shows the areas of London where the sewer network will be at full capacity by 2050, with associated flooding risk.
17 per cent of permeable ground surface in London has been lost over the last 40 years, largely thanks to the trend for home-owners to pave over their front gardens. This has effectively ‘waterproofed’ the city, driving more rainwater into London’s traditional drainage system which is already 150 years old. Without action, in time the capital could be vulnerable to flooding caused even by normal rainfall. At the same time the Mayor is supporting a much-needed modernisation of the London sewerage system through the construction of the Thames Tideway Tunnel – a major new sewer that will protect the River Thames from sewerage overflows. Bazalgette Tunnel Limited are constructing the Tunnel and will sponsor the creation of a full-time post at the Greater London Authority to work in concert to implement the London Sustainable Drainage Action Plan.
The draft plan was launched by the Deputy Mayor for Environment and Energy Matthew Pencharz at a new rain garden in Tower Hamlets, part-funded by the Mayor of London. The site, formerly the dead-end of a public highway which attracted fly-tippers and anti-social behaviour, has now been transformed into a new public space, combining the functions of flood defence and a new cycle route, edible plant gardens and outdoor seating. This approach is backed by Thames Water, who are announcing £20 million funding for similar innovative projects.
The Deputy Mayor for Environment and Energy Matthew Pencharz said:
“Sustainable drainage is a win-win for London – reducing flood risk while also increasing the amount of green space in our city, which is great for providing new community spaces, improving air quality and beautifying our streets. We need new sewers like the Thames Tideway Tunnel but cannot keep building them endlessly, which is why sustainable drainage is necessary. Today’s action plan is just part of a wider initiative by the Mayor of London to encourage sustainable development, which is vital to support our city’s population as it continues to grow.”
Thames Water Director Richard Aylard said:
“We work really hard to make sure our sewers are as empty as possible whenever heavy rain is expected but it’s important we also look at how to reduce surface water getting into them in the first place. We’ve set aside £20 million to help support sustainable drainage projects across our patch over the next five years. Our aim is to help create at least 20 hectares, which is equivalent to about 30 football pitches, of green infrastructure to capture rainwater by 2020.”
Chair of London Councils’ Transport and Environment Committee Cllr Julian Bell said:
“Flooding is a very real threat for significant numbers of people in London and London needs a robust and sustainable response to address this now to avoid an even bigger problem in the future. The plan contains some key measures which, if implemented in a timely way and correctly, will be of real benefit. The net increase in London’s green infrastructure will not only make London a better place to live but will also reduce the amount of rainwater entering the sewer system and hence reduce the risk of flooding.”
Deputy Director of London for the Environment Agency Simon Moody said:
“The government is allocating £12 million over six years to help London boroughs manage surface flood risk, but these projects alone will not eliminate the threat. The London Sustainable Drainage Action Plan identifies opportunities to manage rainwater sustainably for the benefit of the people, businesses and environment of London. I welcome the consultation and hearing from other organisations about how they can help deliver this ambitious plan.”
Tower Hamlets Cabinet Member for Environment Cllr Ayas Miah said:
“As a borough along the River Thames, it is important that we work with the Greater London Authority, Thames Water, the Environment Agency and London Councils to implement this plan. We are very proud of the transformation that has taken place here at Derbyshire pocket park, offering residents an open space and alleviating some of the flood risk.”