Knostrop Footbridge

Structural Designer

Mott MacDonald

Client Name

Leeds City Council

Location

Leeds, United Kingdom

PRINCIPAL CONTRACTOR
BAM Nuttall

ARCHITECT
Knight Architects

FABRICATORS
SH Structures Ltd Images: © Paul White & Mott MacDonald

PROJECT DESCRIPTION

Knostrop Footbridge forms part of the Leeds Flood Alleviation Scheme, connecting the Trans Pennine Trail over a new moveable weir on the River Aire in Leeds. The 70m bridge consists of a four span externally painted weathering steel box girder with a curved soffit. The bridge sits on slender piers, which cantilever forward from the tapered ends of the weir walls below. The bridge’s width varies throughout its length, using a graceful plan curvature to create viewing areas above the piers.
 

Judge's comment:

The elegant Knostrop Footbridge spans the River Aire in Leeds, over a new weir, part of the Leeds Flood Alleviation Scheme. The four spans of the continuous steel box girder are supported on very thin, 2.5m high by 50mm thick, vertical steel plates bolted and cast into the concrete walls between the weirs. Viewed from up or downstream, these plates are hardly visible so that the bridge appears to float over the river. The box girder is made from painted weathering steel and has a smooth curved soffit, changing shape and width to create a gentle sinuous form that gives viewing places above the weirs. Very tight tolerances, an accurate survey of the concrete walls, and a trial erection at the steelworks were all needed to ensure a perfect fit. This beautiful bridge reconnects popular footpaths on either side of the river and gives the passing pedestrian or cyclist a moment for the very human enjoyment of watching falling water.