London Flood Risk Report Calls for Exemplar SUDS Projects

Darren Johnson, deputy chair of the London Assembly’s environment committee said it was ‘pure  luck’ that the city had so far avoided devastating floods similar to those experienced elsewhere in the UK.   Introducing the “For A Rainy Day” report, the committee is calling on the Mayor to  press forward action to address the serious risk of flood damage.

Amongst the committee’s key recommendations are to improve public access to flood risk information and ensuring that the ‘Drain London’ initiative mapping the capitals surface water flood risk is readily accessible to the public.  The committee also calls on the Mayor to improve communication of sustainable drainage solutions in developments.

In particular, the report calls for more exemplar surface drainage schemes with visible value and demonstrable workability, across a range of development types.

The report recommends that the Mayor extends the applicability of the Green Roofs Fund to include other forms of sustainable drainage to support more exemplar projects to stimulate commercial interest.   Where possible, the Mayor should also ensure that the GLA Group estate exemplifies sustainable drainage in its own property works

The report points out that  sustainable drainage is still rarely retrofitted to existing built areas in the capital, and the level of sustainable drainage in new developments varies.  Developers are slow to take up sustainable drainage, especially on brownfield sites:

The report says:  ”Under 2006 Supplementary Planning Guidance, it is essential that developments use sustainable drainage wherever practical, and achieve 50 per cent attenuation of the undeveloped site’s surface water runoff at peak times; it is the Mayor’s preferred standard that developments achieve 100 per cent attenuation.  However, developers see obstacles to fully sustainable drainage, pointing out that 96 per cent of development in London takes place on previously developed land.  Progress is therefore slow and the UK lags behind other countries in the extent of sustainable drainage.  Site owners and developers see sustainable drainage as a relatively untried new technology, and therefore approach it with caution.  More examples of successful sustainable drainage with visible value and demonstrable workability, across a range of development types, could help to overcome this. The same kind of initial problems had to be overcome in the early years of ‘traditional’ drainage engineering”

The committee also calls on the mayor to:

• Retain and show a plan to achieve his target to restore 15km of rivers in his Climate Change Adaptation Strategy.
• Support a call for water companies to be able to work directly with householders to correct misconnected drains.
• Take steps to identify and secure funding for work to reduce flood risk in London.

For further information visit the London Assembly’s For A Rainy Day page

Read the London Assembly’s Press Release