Findhorn Bridge was built from 1924 to 1926, and carried the old A9 highway for two spans over the River Findhorn. An inscription on the bridge states it was built as a replacement for a Thomas Telford structure of 1833, although it is likely that Telford's bridge had in fact been lost earlier. The bridge was built by Sir Robert McAlpine and Sons for £36,120.
Owen Williams, with Maxwell Ayrton as consulting architect. The two worked together on a number of bridges, and Findhorn Bridge is generally thought to be one of the most successful examples. On earlier schemes, such as the now-demolished Lea Valley Bridge, Ayrton's main contribution was to add monumental towers at the ends of the bridge, structurally irrelevant but marking the bridge as a gateway structure. For the Findhorn Bridge, the choice of a structural form which could be monumental in its own right, led to a happier collaboration.
So far as I am aware, there's nothing quite like Findhorn Bridge anywhere else. It has two 29m spans, each broadly of the Vierendeel truss type, in massive reinforced concrete. That in itself isn't completely without precedent. What is unusual is the architectural treatment of the bridge.
filleted corners. Where applied, the fillet enhances the strength of joints between the vertical and horizontal truss members, the joints being subjected to particularly high stresses in a Vierendeel design. In the Findhorn Bridge, the upper fillets have essentially been massively extended until a semi-octagonal opening is formed, instead of a rectangular one.
Nonetheless, the bridge has a considerable portion of charm. Much of this comes from the shaping and detailing of the various elements. For example, the outer face of the parapet wall is inclined inwards, keeping it visually distinct from the main truss elements. The vertical members have a chevron groove at their top which enhances the visual impression of it being a colonnade rather than a truss. The crossbeams below the deck are fish-bellied, reflecting the way the designer presumably understood the stresses to be distributed.
- Google maps / Bing maps
- Engineering Timelines
- British Listed Buildings
- Highland Council Historic Environment Record
- Scottish Highland Bridges
- Owen Williams Bridges in Scotland
- British Bridges (Public Works, Road and Transport Congress, 1933)
- Highland Bridges (Nelson, 1990)
- Owen Williams (Yeomans and Cottam, 2001)
- Civil Engineering Heritage - Scotland Highlands and Islands (Paxton and Shipway, 2007)
- An Encyclopaedia of Britain's Bridges (McFetrich, 2010)