Roads are usually thought of as hard, impermeable surfaces that transport surface water quickly into the drains and sewer network. Roads together with pavements and verges can form an important part of a holistic stormwater management strategy by replacing the impermeable surfaces with permable ones and designing in BG features. Among other benefits, as part of an integrated design, would be increased safety due to reduced ponding, e.g. for cyclists, and a water source for green infrastructure [ACA05].
As part of the current rolling-maintenance regime where the all surfaces are replaced over the course of time, the costs can be equivalent to using standard materials when considered part of a holistic solution [ACA07, PT-2].
Following the GLA announcement "Crossrail for the bike", there is an opportunity to deliver a multi-functional solution in support of BG solutions.