Roadside Rain Garden in Portland, Oregon (photo by Dusty Gedge)The idea of rain gardens since spread to various cities across the US, most notably Portland, Oregon, where the city’s chief landscape architect Tom Liptan championed the idea, initiated various trials and produced guidance that allowed citizens to get involved by creating rain gardens in their own gardens or on adjacent verges. Tom emphasized the importance of multi-functionality, with rain gardens being promoted as attractive landscape features in their own right, as well as being drainage features. Now the rain garden concept has a foothold in the UK, with a few projects around Stroud, in South Wales, London and now in Portslade as part of the Brighton & Lewes Downs Biosphere programme of environmental improvements.
Rain Garden replacing pavement in London at Wardens Grove, Bankside (photo by Gary Grant)Following a scoping study in Portslade – undertaken by Brighton & Hove City Council, The Ecology Consultancy and the Green Infrastructure Consultancy, with funding from Natural England – a number of green and grey spaces were identified where rain gardens could be established to help tackle surface water flooding problems by diverting some of the excess water entering the drains. The idea of the two new rain garden pilot schemes now established at Lockshill (Portslade village green) and Victoria Recreation Ground is that surface water runoff is re-directed into small basins or ‘swales’ from which it can slowly infiltrate into the underlying chalk or evaporate or transpire through plants later. These features in Portslade have also presented an opportunity to create two new wildlife habitats, by planting local wild flowers in to the chalk banks and seeding the damper hollows with wetland plants.
Creating the new Rain Garden at Portslade village green (photo by Rich Howorth)Although these new rain garden pilots are relatively small-scale, we hope that they will be the forerunners of many similar schemes in the Biosphere in the future, to help to reduce flood risk whilst bringing more nature to town. Such natural benefits are vital to sustain our urban quality of life and help cope with the effects of climate change. Gary Grant, Director of The Green Infrastructure Consultancy & Lead Author of the UK Rain Garden Guide His new book “The Water Sensitive City” is published on the 8th April 2016