Newquay Island Suspension Bridge, Cornwall
Location N 50°24’56.85”
Span 30.5m (100 feet)
Width 1.32m (4 feet)
Status Open (Private)
Designed by Louis Harper (1868-1940)
Manufactured by Harpers Limited, Craiginches Ironworks, Aberdeen
Level of Evidence that this is a Harper Bridge: Definite
The basis for this is the easily recognised features seen in the early photographs, the unique Louis Harper finials, contemporary press reports and family knowledge. The original nameplate is obscured by the later concrete.
This bridge at Newquay connects the sea stack Island to the mainland and was probably commissioned by the owner of the property on the adjacent mainland. There was a summerhouse on the island as seen in George Washington Wilson’s photograph. This also shows the towers to have been lattice in type. At some subsequent stage the towers were encased in concrete, presumably to protect the steel from the marine environment – a technique also seen in the West Indies.
The main cable may be original, but the platform cable was replaced and routed round the base of the tower rather than through it. Both sets of cables lead to a common anchorage.
A few years ago the hangers were renewed using stainless steel. However, this was incompatible with the mild steel of the main cable which started to deteriorate. Engineering firm Free4m Consulting investigated the history of the bridge to try to find a solution, and tracked down Douglas Harper. He was able to produce an example of an original hanger, which turned out to be the key to solving the problem of how to renovate the bridge.
All 98 hangers were replaced (again), replacing heavy clamped hangers with a more elegant design involving bending each steel hanger around the supporting cables using only a hand tool, as had been done originally in 1900 (see Technical/Suspension). This return to the original elegant design incidentally took perhaps a third of a ton of weight off the bridge.
This restoration won the 2019 Heritage award of the Institution of Structural Engineers. Previous winners include the Forth Rail Bridge, the Hoover Building, the Supreme Court of New Zealand and the Cutty Sark.
In July 2021, the award was presented by Newquay's mayor to Douglas Harper, who accepted it on behalf of the conservation project and the engineers. The judges said that they were "particularly impressed by [the] minimalist approach which was underpinned by detailed research and sound engineering judgement. This is a beautiful piece of conservation and extension of structural design life carried out extremely well. An existing structure with a new lease of life through minimal modifications is a prime example of good proactive sustainable structural engineering."
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