The Sports Turf Research Institute - Showcase

Sustainable Drainage

The increased incidence of flooding in the UK over the past twenty years has led to planners looking at the whole area of urban drainage. It has become clear that the sudden flush of surface drainage water from roads, car parks and other hard surfaces can lead to a sudden increase in river levels downstream of a town or city. 

In order to attenuate the flow rate of water more soft, porous surfaces are being created. These may range from porous pavements to grassed channels or swales to channel drainage water slowly into the underlying soil. However, in existing sites such as car parks it is extremely difficult to introduce such systems.

STRI, with funding from WRAP, is looking at the potential for a system of retro-fitted sustainable drainage for car parks. These consist of plastic grids within which compost is held to a depth of, at least 50 mm. These are placed in the middle of individual parking bays. The compost is seeded with an appropriate grass mixture. The current trials are investigating the actual potential for drainage attenuation by such systems as well as monitoring the ability of different grass species to establish and grow in such schemes.

Apart from the ability of the grid systems to ‘stretch out’ drainage it is expected that they will also absorb any leakages of oil from the parked vehicles.