Southern Water has completed a driveway upgrade scheme in an Isle of Wight village to replace paved surfaces for porous surfaces to protect homes and local drainage from deluges of surface water following heavy rain.

Photo: before and after picture of a driveway

The company reimbursed residents of Binstead, near Ryde, to replace their impermeable paved and concrete driveways and yards with permeable alternatives such as gravel and cobblestones. This slows the flow of rain by allowing it to slowly be absorbed into the environment instead of running straight into drains and the combined sewer network, where it joins with wastewater.

Over 430 square metres of impermeable surfaces have been removed during the pilot, with residents offered up to £75 per sqm replaced. If 10mm of rain were to fall on that area in one downpour, it would create nearly 2.5 tonnes of surface water, which would run into the Southern Water network. This water will now be absorbed into the environment instead.

A driveway that has had work carried out so water can drain more naturally, which helps to reduce storm overflows

Residents in the village have experienced a number of flooding events in recent years, largely due to this excess surface water, and the ‘de-paving’ pilot is one of several measures Southern Water, Isle of Wight Council, and the Environment Agency are taking to tackle the problem.

The Binstead storm overflow has had to activate up to 20 times a year to prevent further flooding of homes and businesses when sewers have become overloaded with surface water. The de-paving scheme is part of wider efforts to reduce reliance on storm overflows.

Southern Water plans to use data gathered from the scheme to inform a wider roll-out across the South East, with the aim of replacing around 4,000 non-permeable driveways and more than 1,100 hectares of hard surfaces over the next five years to reduce storm overflows and associated flooding.

Southern Water engineer Harry Buckingham, who has headed up the pilot, said:

“The increase in paved gardens and driveways in the UK makes flooding more likely and contributes to storm overflows being activated. We are committed to reducing overflows and helping customers to slow the flow of water entering the system through measures including water butts, soakaways and permeable driveways.