Humans and wildlife catered for at Knostrop Weir Bridge

Words:
Hugh Pearman

Public works as a matter of civic pride

Aerial view shows the relationship of the bridge to the echelon of weirs and the lock island.
Aerial view shows the relationship of the bridge to the echelon of weirs and the lock island. Credit: Paul White

Knostrop Weir on the south-eastern outskirts of Leeds is part of an ambitious flood alleviation scheme started after the devastating River Aire floods which hit the city at the end of 2015. It provides two things: an echelon of three new pneumatically moveable weirs that can rapidly be lowered to let floodwater discharge quickly downstream; and a shared foot and cycle bridge, part of the Trans Pennine Trail, which perches on the weir abutments as what our judge Yuli Cadney-Toh called a 'hoppity bridge'.

Working with engineer Mott MacDonald, Knight Architects has produced a 70m bridge which is a pleasingly elegant and dynamic thing in its own right, its undulating edges providing three wider points on the deck where it is tempting to linger to watch the smooth rush of water, nearby boats, or wildlife (it was designed with the transport needs of fish, eels and otters in mind as well as humans). On the sunny, cold winter’s day I visited, it was well used by the public. Visually it dissolves from a distance: it is a surprisingly unobtrusive design in this industrial and post-industrial landscape, minimising structural bulk by having the weir walls double as foundations for the bridge.

  • Industry, engineering and architecture combined – Knostrop Bridge hops across the new flood weirs.
    Industry, engineering and architecture combined – Knostrop Bridge hops across the new flood weirs. Credit: Paul White
  • Look carefully and you’ll see an otter ramp on the far bank. Eels and fish passes are also integrated.
    Look carefully and you’ll see an otter ramp on the far bank. Eels and fish passes are also integrated. Credit: Paul White
  • The bridge perches lightly on the abutments of the moveable weirs.
    The bridge perches lightly on the abutments of the moveable weirs. Credit: Paul White
  • This is an understated and sophisticated design that is simultaneously minimal and generous.
    This is an understated and sophisticated design that is simultaneously minimal and generous. Credit: Paul White
  • Site plan – the bridge forms a vital pedestrian and cycle link in the Trans Pennine Trail.
    Site plan – the bridge forms a vital pedestrian and cycle link in the Trans Pennine Trail. Credit: bmmjv and KA
12345

All the judges liked the fact that an engineering-led project of this kind should consider the amenity and convenience of the public and be part of an overall landscape improvement of this alternative route into and out of the city, 'taking people to places they might not have gone' as Kathy MacEwen put it. For me, it displays a clear intelligence and commitment to the old idea that public works are a matter of civic pride.

See more MacEwen Award