A well-connected, enterprising 21st-century village community which will protect and create over 1,000 jobs across a variety of employment types, provide a wide range of homes, offer the opportunity for local governance, and deliver innovative means of healthcare services; all set within a rich green and blue infrastructure network associated with the working countryside.

The proposal sits along the corridor of the River Bourne and covers a range of flood risk classifications from 3a (functional flood plain), at the river’s edge, to 1 along the northern boundary. The landform, being an old airport is fairly flat and generally unhelpful to surface water flows towards the river. The 128 hectare site is also split across three local authorities; Surrey Heath District Borough Council, Runnymede District Borough Council and Woking District Borough Council.

A key aspect of our appointment was the development of a flood risk assessment and sustainable drainage strategy to support the outline planning application. Working with the landscape architects and the masterplanners, we developed a Strategic SuDS Network comprising of a series of above ground open green and blue features.

‘The Rills’ flowed north-to-south and form part of the Strategic SuDS Network. The Rills were proposed as conveyance features but also contributed to the attenuation requirement during an annual exceedance event. The Rill collected and conveyed the surface water runoff from the individual catchments southern towards the Bourne.

At strategic locations, The Rills were intercepted by a series of blue/green corridors that run eastto- west across the site and largely follow the existing topography and are therefore largely flat; these blue/green corridors also formed part of the Strategic SuDS Network. The principle blue/green corridor is known as ‘The Ride’ The Rills pass through these blue/ green corridors’ at these junctions surface water runoff is restricted by flow control devices set at an appropriate rate to mobilise a series of vegetated detention
basins and attenuate surface water flows.

The Strategy SuDS Network was also designed so that it could be utilised to provide exceedance flow routes from each development parcel to the Bourne.