Challenge

An ambitious landscaping solution required ACO to create a sustainable drainage system to control rainwater run-off while providing a high-quality habitat for wildlife to flourish at the new Gloucester Gateway M5 motorway services.

The solution need to be sensitive to its local green field surroundings, reduce flood risk, maximise bio-diversity and create amenity areas.

Solution

ACO KerbDrain, Qmax and ACO Swale Inlets were combined to integrate with a full SuDS solution, creating amenity areas for people and wildlife alike.

Project detail

The design of the site needed to be similarly sensitive to the needs of the locality, given the site’s location on the edge of an area of outstanding natural beauty. This involved shielding much of the site from key vantage points by means of large-scale screens created by curving green roofs over both the main buildings.

The drainage strategy also reflected this principal, linking together an extensive array of sustainable drainage features across the site including swales, bio-retention areas and filtration strips, which ultimately discharge water to a pond and wetland area.

ACO worked with project designers BWB Consulting Engineers, and the specialist contractor, The Buckingham Group, to deliver a sustainable drainage system across the 265 car parking spaces plus 35 HGV bays.

ACO KerbDrain was the main channel drainage solution, selected due to its combined kerb and drainage usage. 447m were used to demarcate the parking bays while conveying water away from the impermeable surfaces. Rodding eyes and gully top units were also integrated as part of the design, for easy access for maintenance.

The SuDS design linkage involved specially adapted connections that were installed in five locations on the back of the ACO KerbDrain runs. This linked to five ACO Swale inlets, draining water at regular intervals into the swale, to feed planters used to green the public areas around the service facilities. The surface finish and the flared outlet of the ACO Swale inlets unit encourages water dispersion and reduces excessive flow velocities into the swale, reducing soil erosion.

The design also called for 150m of ACO Qmax 350 high-capacity slot drainage in the HGV parking bays. The F900 load class of Qmax, with the integrated ductile iron edge channels, meant the drainage solution could cope with the heavy vehicles pressures. Four Qmax 225/350 outlet chambers were also supplied for maintenance ease.

Result

The result is a site that reduces flood risk, maximises biodiversity and creates amenity areas to be enjoyed by all. The clients, Westmorland Ltd and the Gloucester Gateway Trust, partnered with the Building with Nature scheme to ensure the building benefits wildlife and increases biodiversity.

Water has been used to attract new species in the ponds, and the site also has bat boxes and raptor boxes for kestrels, as well as insects in the stone wall cladding of the buildings. Over 1000 trees have been planted on site, including an orchard, with the ‘growing communities’ project.