University research into sustainable drainage systems will help manage future flood risk
Managing surface water effectively is vital to prevent drainage systems from being overwhelmed during heavy rainfall events. Researchers at the University of Hull have created a ‘living lab’ with sustainable drainage systems on the campus to help identify the best ways to reduce the risk of flooding in urban environments.
Sustainable drainage systems (SuDS) are methods of managing water drainage in urban environments that aim to mimic natural drainage by slowing the flow of surface water and filtering it to reduce pollutants before it reaches watercourses. They have an important role to play in helping society adapt to the consequences of climate change – which is expected to bring more frequent heavy rainstorm events. We know that 100,000 homes in Hull and the East Riding are at risk of flooding and SuDS are key to Living with Water’s Blue-Green vision to manage flood risk in the region.
The University of Hull’s ‘SuDSlab UK’ project is being led by its Energy and Environment Institute, and its Blue-Green Lab involves 300 sensors being installed across the 50-hectare Cottingham Road campus that monitor the effectiveness of the drainage systems in place there.
The Institute’s Deputy Director and SuDSlab UK academic lead, Dr Stuart McLelland, said: “As well as reducing surface water flooding, and the demands heavy rainfall places on water treatment plants, SuDS aim to improve water quality, increase biodiversity and enhance the amenity of urban environments through the creation of attractive green spaces.
“The monitoring and measurement framework we’ve put in place through the Blue-Green Lab means we’re learning how our existing drainage systems work and can use that information to help us understand the best solutions for a range of environments.
“Partners in the project include Hull City Council, Yorkshire Water and the University’s Flood Innovation Centre, all of which have an understandable interest in the findings from our research.”
So, what does a sustainable drainage system look like? Visit the Blue-Green Lab at the University and you won’t have to look far to find a range of examples – though at first glance you may not realise that’s what they are.
That’s because most of them blend in with and enhance the appearance of the campus. For example, what look like areas of planting close to many of the buildings are actually detention basins – shallow depressions covered with vegetation that hold and slowly drain rainfall.
Likewise, a larger, fenced area of planting close to the Wilberforce multi-storey car park on the site is a ‘swale’, created specifically to hold and drain rainfall from the car park’s roof - rainfall that would otherwise end up directly into the drainage network, potentially overwhelming it.
Perhaps one of the most attractive SuDS on the campus is a corridor of plants and trees flanked by newly-built student accommodation blocks. Look closely and you’ll see the plantings are in shallow hollows that provide storage for water, but the overall effect is of a shady, green oasis with bench seating where students can enjoy being outdoors.
The best-hidden SuDS on the site is a long, wide walkway linking the main campus buildings to these student accommodation blocks. This ‘permeable pavement’ looks like an ordinary footpath but water poured on it is absorbed as if by magic, because it is constructed from a porous material that catches rainfall and surface runoff and stores it in an underlying reservoir, from where it slowly discharges.
Data from each of the SuDS described above, and all the others across the campus, are captured by sensors at five-minute intervals and sent to a central hub. You can see details of the locations of all the sensors on the SuDSlab UK website and live data are available online.
“The data from our monitoring equipment, which includes sensors in boreholes at depths of up to 40 metres, tells us where water is and what’s happening to it at different stages of the drainage process,” said Dr McLelland.
“We’re monitoring rainfall and tracking soil moisture, water depth, flow rates and temperature and electrical conductivity as a measure of water quality.
“All of this will lead to a better understanding of how SuDS can be made more efficient in a range of environments.
“As well as helping us manage water on the University campus, our learnings can in turn help organisations, towns and cities both in our region and beyond manage water more sustainably. This will become more important than ever if we are to meet the challenge of climate change in the future.”
Find out more about the wider SuDSlab UK project and the on-campus SuDS at the Blue-Green Lab here.
To arrange a tour of the Blue-Green Lab on the campus please contact sudslabuk@hull.ac.uk.