The Great North of Scotland’s coastal route between Portsoy and Elgin crossed the River Spey on a mammoth viaduct close to its mouth, east of the village of Garmouth.

The project not only involved erection of the structure but also measures to confine the Spey to the middle of three channels into which it split during floods. This channel was spanned by a single bowstring structure measuring 368 feet in length and 40 feet high. Either side of it, identical approach viaducts were formed comprising three 107-foot lattice girder spans. Construction got underway in June 1883, carried out by Blaikie Brothers, a firm of contracting engineers from Aberdeen.

The paired masonry-clad piers were formed of concrete-filled iron cylinders, some of which were sunk to a depth of 50 feet before bedrock was encountered. Steam cranes and a riveting machine greatly quickened the assembly of the ironwork. Such were the benefits of this cutting edge technology that only 40 men were needed – the riveter fixing 900 rivets in a single day. With the final one inserted on 22nd October 1885, the structure was substantially complete, weighing in at 588 tonnes and able to withstand a rolling load of 354 tonnes.

Confining the uncooperative Spey to a preferred course was a battle which took many men many months to win. The structural integrity of the bridge and its approach embankments were compromised by flooding on several occasions. Despite this, goods trains began to roll across the viaduct on 10th April 1886. Passenger services followed three weeks later. Its cost exceeded the original £25,000 estimate by £15,000.

On 4th May 1968, the structure retired with the closure of the line. Dismantling of the railway got underway in the autumn but the viaduct survived due to the costs of safely salvaging it. In 1980, Moray District Council lifted any remaining threat of demolition by taking control of the viaduct and, a year later, it became part of the Speyside Way footpath.

Source

Much of this information came from John Ross’ excellent and authoritative book ‘The Spey Viaduct’ which is available through the website of the Great North of Scotland Railway Association.