For this major regeneration scheme northwest of Leeds city centre we are providing multidisciplinary engineering and infrastructure services to transform a contaminated 25-hectare brownfield site into a diverse and sustainable mixed-use community.
Our full scope of work covers the infrastructure design, including a new highway and bridge linking to the new railway station; geotechnical design, including the road embankment and specification of a reinforced soil wall; earthworks design and specification; ground and groundwater contamination remediation design and specification; and the design of utilities associated with the highway and initial phases of redevelopment.
Background
First established by Cistercian monks, in the 12th century, Kirkstall Forge is claimed to be the longest continually used industrial site in Britain. Following its closure in 2002, the site was acquired by CEG and is currently undergoing a £400m regeneration to provide around 1,000 new homes, commercial, retail and leisure facilities, alongside a new railway station providing a direct link from this riverside setting to the city centre.
Design quality and innovation
Infrastructure and connectivity were seen as of strategic importance by the client and local authorities. To support this, our approach provided an infrastructure that could be implemented in phases, adapting to commercial, retail or residential use without constraining the rest of the development.
The innovative design developed from this addresses the complexities of the steeply sloping site, bisected by the River Aire, through creative adaptation of standard solutions to meet specific challenges. Replacing 210m of the northern river bank and 125m of the southern with reinforced earth retaining walls has raised them by five metres in order to create suitable highway gradients and support the 30m span bridge, central to the connectivity of the site.
This new bridge is founded on concrete bank seats built directly on the reinforced soil structures and is the first in the UK to use this construction method to span a river. At 18m wide, it supports three traffic lanes and wider than normal footways designed to encourage pedestrian use and support the public realm strategy.
In a further first for the UK, a cantilevered pedestrian platform is founded directly in the reinforced embankment to overhang the river and further enhance the public realm.
Sustainability
A number of design decisions, including the remediation criteria and the earthworks specification, have resulted in the on-site retention of excavated materials excavated. Most were processed and sustainably re-used during the enabling works whilst limited quantities were held for future phases of development.
Collaboration
Complex stakeholder involvement and buy-in was key to the success of this project. During construction our civil and structural engineers acted as lead consultant coordinating all multi-discipline engineering matters and reporting directly to the client’s representative.
Impact
The completed infrastructure and enabling works have already had a significant impact on the regeneration of the area, allowing benefits to be realised prior to development of buildings on site and creating a robust framework for further transformation.
Resonating with the UK government’s plans to improve economic growth and connectivity across the north of England, Kirkstall Forge will improve the local environment and create around 2,400 new jobs, boosting the local economy by more than £5m per year.
The development has recently been included in a showcase portfolio of Northern Powerhouse projects with which the government aims to attract Chinese investment in the region and the Phase 1 works were highly commended for ‘Best Brownfield Infrastructure Project’ in the 2016 Brownfield Briefing Awards and won a Placemaking Award in 2015.