Soil systems

The existing ‘made ground’ at Mayfield was used to build structural elements such as pathways, with imported soils used for planting areas. © Richard Bloom

Collaboration is key for making best use of challenging soil conditions. LI Award-winner, Mayfield Park, highlights the need for a landscape-led approach to guide decision-making and inform progress.

Max Aughton

Designed by Studio Egret West (SEW), Mayfield Park is a new 6.5-acre park on a former industrial site just minutes from Manchester’s Piccadilly railway station. It is the first new public park to be built in the city centre in over 100 years, and consists of a new green space with the restored River Medlock flowing through its core. The park is the jewel in the crown of the transformational £1.4 billion Mayfield development.

Delivered for the Mayfield Partnership, Civic Engineers led the contractor team for PP O’Connor through RIBA Work Stages 5 and 6. The collaboration between engineers, the landscape architect, and the soil scientist played a crucial role in solving the complex challenges presented by a site with a 300-year history of environmental neglect and industrial damage.

Lying derelict for over 30 years, the site has been repurposed into a public green space that celebrates the heritage of the area and exemplifies sustainable construction practices. Following demolition of the existing structures, the site was levelled and enabling works undertaken. This included the reuse of approximately 9,000m3 of ‘made ground’ soils – natural soils that have been largely replaced by man-made materials. The ground remediation strategy, originally developed by ROC and overseen and implemented by Buro Happold, was carried out through a separate construction contract that preceded the main park works. This process allowed much of the site-won material to be reused for landform and footpath bases.

For those areas designated for planting, a different approach was needed. Testing by Tim O’Hare Associates (TOHA), confirmed that the volume and quality of substrate extracted from the site-won material was insufficient and too diluted to withdraw from the bulk excavation.

SEW collaborated with TOHA to create a range of imported topsoils, subsoils, and sands, developing bespoke soil profiles tailored to support a variety of planting types, habitats, and specific tree pit needs (read more from Tim O’Hare about manufactured soils on page 54).

The Mayfield Park development has demonstrated that, even in an urban environment with a rich industrial history, a landscape-led approach can realise real benefits in terms of optimising soil reuse, carbon reduction, biodiversity, and climate resilient drainage design.

Critical to the implementation of this approach on projects such as Mayfield is the understanding that the environment functions as a single system and that the soil beneath our feet is central to how all these functions interact. An early understanding of the landscape, soil, and ground conditions is critical to maximising opportunities and creating spaces where people can lead happier and healthier lives.

Max Aughton is a Project Landscape Architect at Studio Egret West