3 Aug 2011
Let’s face it: drainage has a pretty unromantic image. For most, it’s a prosaic, practical necessity – out of sight and out of mind. The idea that it could somehow deliver a net benefit to the natural environment requires a huge leap of faith.
Yet redefining drainage as an ‘ecosystems service’ is no pipe dream. It’s a vision of the future in which stormwater is brought out of the pipe, above the ground and is directed into health-giving green veins and blue arteries across our towns and cities.
That’s the future glimpsed in the Government’s Natural Environment White Paper http://www.defra.gov.uk/environment/natural/whitepaper/ , as part of its broad and ambitious mission to join up our green spaces and create a countrywide green infrastructure with balanced ecosystems and rich biodiversity.
Fragmented and Fragile
The White Paper was supported by the first UK National Ecosystem Assessment (NEA) http://www.defra.gov.uk/environment/natural/uknea/ a major piece of research that looks at the benefits the natural environment provides to society. It concluded that over 30% of the services provided by our natural environment are in decline. The Lawton Report Making Space for Nature http://archive.defra.gov.uk/environment/biodiversity/documents/201009space-for-nature.pdf, also demonstrated that the UK’s natural environment has become fragmented and fragile.
The White Paper is as a much a statement of vision as it is a pre-cursor to heavy handed legislation, but it does set out an approach to green infrastructure, and to developing living urban corridors with goals for wildlife, water and soil systems and landscaping.
Ecosystems Services are described as ‘products of natural systems from which people derive benefits’. Sustainable drainage systems are identified as providing a ‘regulating service’, helping to achieve ecological balance in the urban environment. They provide an opportunity to deliver multiple benefits, whilst increasing flood resilience.
So, for example, wetlands and other SUDS schemes will support water purification. The green/blue corridors created by open watercourses and bioretention schemes will provide a cooling effect to the local climate. Trees and vegetation will support carbon capture and combat air pollution. Together they provide a connected network for wildlife.
With the Pitt Review and the Flood and Water Management Act http://www.engineeringnaturesway.co.uk/policybriefing/flood-and-water-management-act/ it may seem like we are making huge progress with SUDS – and we are. But the White Paper takes a much longer view and shows there’s still a long way to go. In particular, we’ll need to move toward a pro-active policy of retrofitting SUDS.
We’ll also need to tackle the misperception that SUDS are integrally ‘natural’ ; understanding that there’s a difference between systems that deliver benefits to nature, and systems that are ‘natural per se’. Every SUDS scheme is engineered using ‘hard’ or ‘soft’ elements or a mixture of both as appropriate. Often it’s hidden manufactured systems that make the above-ground natural features possible. Without this understanding many SUDS schemes could be left on the drawing board.
The precursor to the Natural Environment White Paper was the historic Nagoya http://www.defra.gov.uk/news/2010/10/29/nagoya-statement/ agreement in 2010 that set out ambitious global targets agreed between 190 countries. It sets out clear biodiversity goals for the world by 2050.
So what will our future towns and cities look like? Most of us have been brought up on a Hollywood image of the futuristic metropolis without a tree or a watercourse in sight. It’s comforting to note that if we get it right, future generations may enjoy a greener and bluer urban environment than we might ever have hoped for.
Photo courtesy of Illman Young Landscape Design