Later this year, TTL will be looking to explore ways in which we can all work together to mitigate the risk of flood in our town, whether from rivers or surface water. Inspiration could come from the Brighton & Lewes Downs Biosphere Project, which has just completed a pilot project to create the first ever ‘Rain Garden’ in the Biosphere area, with two schemes to be established in parks in Portslade.
A rain garden is simply a low-lying area of ground containing plants tolerant of wetter conditions, which is designed to receive and retain rainfall from surface water run-off from hard surfaces, thereby allowing the water to slowly drain away over time.
In Brighton and Hove, a feasibility study identified Victoria Recreation Ground and Locks Hill park (Portslade village green) as potential sites to help reduce flood risk in Beaconsfield Road and Portslade village. The rain gardens are created by excavating shallow hollows. Low chalk banks are then planted with native species of wildflowers typical of both wetlands and local chalk grasslands to attract wildlife.
The hope is that not only will these rain gardens help to alleviate the threat of localised flooding, they will also help reduce pollution of the underground chalk aquifer from urban runoff.
Left: Creating the new Rain Garden at Portslade village green (thanks to Gary Grant; photo by Rich Howorth).
Right: Roadside Rain Garden in Portland, Oregon (thanks to Gary Grant; photo by Dusty Gedge).
Whilst a new idea in this country, rain gardens have a long pedigree in the USA – most notably in Portland on the Pacific coast (which gets 42 inches of rain a year compared to 37 inches for the US as a whole).
The great thing about rain gardens is they can be attractive natural features in their own right, helping to increase plant diversity, attract wildlife and provide some natural colour to public spaces, as well as playing a vital role in flood management. Plus they don’t need to be huge to be effective: space in gardens, street verges and shopping precincts can all be put to use. So isn’t it time we put the rain garden principle to use in more of our rain-hit town?
If you’re interested in exploring the idea of rain gardens in Lewes, email us or watch out for more news on our natural flood management events this year.
Rain garden expert Gary Grant, who designed the Biosphere rain gardens and is the author of various books on the subject, explains more about rain gardens here: http://biospherehere.org.uk/rise-of-the-rain-gardens/