Carlisle FAS is a major infrastructure project of national importance for the Environment Agency (EA) resulting from the devastating floods of January 2005. It sets a new benchmark for design quality, innovation, construction and sustainability. Locally the defences protect over 3000 residential, commercial, educational and historic properties including significant public and private infrastructure.
The scheme requirements were to provide a 1 in 200 year flood defence scheme appropriate to the residential, historical and industrial locations along the two environmentally sensitive rivers Eden and Caldew. Opportunities were to be taken to increase the flood storage capacity within the rivers by setting defences back, improve human interaction with the river and enhance the cyclepath network.
The scheme has provided the essential infrastructure for Carlisle’s future renaissance by greatly reducing the risk of flooding, creating new areas of high quality public realm, encouraging development along the river, strengthening and enhancing the sustainable transport network and ultimately turning the city’s focus back towards the river.
Approximate Map Location
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Waterways and wetlands
Commended 2009 LI Awards Urban design and masterplanning
To provide a 1:200 year flood protection along the Rivers Eden and Caldew, providing environmental enhancements where possible.
Engineers: Jacobs, Halcrow.
Carlisle City Council
Raised flood walls were set back from the river, leaving space for riverside paths. Sections of the existing river walls were replaced by railings, opening up new views to the river and providing the opportunity for public art. Raised embankments provided continuity of open green space and footpaths and cycleways were routed along these to provide new and extended views.
Lazonby pink sandstone was sourced from within Cumbria ensuring its visual suitability and reducing road miles, with reconstituted stone, also sourced from local suppliers, reducing the use of virgin stone.
Respecting locally prevailing bonding patterns, brick was used as a cladding material, in those areas where brick was the predominant building material. In areas of restricted working space and environmental sensitivity another innovative solution for a flood defence scheme was developed with Hanson UK. Their QuickbuildTM precast wall panels were revolutionary on this projectcomprising pre-fabricated cladding panels that were constructed off site and lifted into place using cranes in a matter of days. These used the same brick types and bonding pattern as used elsewhere. Construction off-site allowed improved control over the finish quality, reduced healthnd safety risks by avoiding the need for bricklayers to work close to deep water, and reduced environmental risks by avoiding potential polluting activities. These were assembled as the core concrete wall was being constructed.
An innovative technique for flood defence wall facings was devised using concrete formliners. Site specific moulds were taken from carefully selected local stone walling and combined with coloured concrete to create a dramatic, yet sympathetic, finished effect along the river corridor. This approach minimised the volume of concrete used as it eliminated the requirement for additional cladding materials, mortars and associated environmental risks from pollution especially adjacent to the SAC designated river.
AXIS undertook an extensive context review to ensure the Design Guidelines responded to existing materials and townscape features along the river corridor (typically locally appropriate cladding, coping and railing designs) rather than standard flood defence detailing.
Throughout the scheme the opportunity was taken to widen paths to 3m during their reinstatement, providing for mixed pedestrian and cyclist use.