Supporting the creation of a new garden village in Cheshire

In 2015, The Garden Village at Handforth was selected as a possible strategic residential development site by Cheshire East Council. The project aimed to address the continuing housing shortage in the borough. The site comprises a combination of green and brownfield land, including a former Royal Ordnance Factory at Handforth WW2 storage depot and two Environment Agency registered historic landfill sites.

Subsequently, the site was identified as one of the UK government’s new ‘Garden Village’ sites. To support this, technical and master planning studies were undertaken. RSK subsidiary RoC Consulting provided technical ground and civil engineering input into the emerging master plan with a view to identifying potential considerations or constraints, while identifying any potentially abnormal items that might require due consideration in development appraisals.

A programme of site-wide ground investigations was completed to fully understand contamination-related concerns and probable foundation design requirements involving the formation of over 60 exploratory boreholes and trial pits. This work was completed at the same time as a site-wide highways, level and drainage review to determine the most efficient engineering strategy for the site, paying due consideration to the likely development phasing requirements.

As well as ground-related issues typically encountered on brownfield regeneration sites, the presence of an inert landfill site poses a considerable physical constraint to development.

To address this, an earthworks assessment was completed and as much material as possible was retained within the landfill zones, with land regraded and reprofiled to levels and gradient more compatible with development. This was completed in conjunction with ground investigations, during which the advice of ground improvement specialists was sought to determine the landfill materials’ suitability for reuse as engineered fill.

RoC’s technical input in support of the draft supplementary planning document and its engineering assessment on earthworks and drainage design helped to create a development cost plan, within which allowances can be made for any significant remediation or bulk earthworks operations.