And yet Canada keeps the traffic moving...

SCOTTISH Government officials chose not to install ice-clearance devices on the Queensferry Crossing in case they damaged the bridge, the Scottish Daily Mail can reveal.

Two near-identical structures in Vancouver, Canada, have been fitted with collars that slide down their cables and clear freezing chunks of ice.

Government ministers in British Columbia acted after hundreds of vehicles were hit and several drivers injured by falling ice during a cold snap in 2012.

The cable collars were last deployed only a month ago during a severe wintry blast that left the city under six inches of snow. A handful of ‘ice bomb’ incidents were reported but the Port Mann Bridge remained open to traffic, while the Alex Fraser Bridge shut for only an hour.

Vancouver – which has a similar climate to Scotland’s Central Belt – also uses de-icing spray on the cables ahead of predicted snowfalls.

However, Scottish Government agency Transport Scotland last night admitted it had turned down the idea of using the collars because they ‘may damage the cables’.

Ice accretion is a problem often encountered by cable-stayed bridges in colder climates, including the Veterans’ Glass City Skyway Bridge in Toledo, Ohio, which has the familiar ‘sail’ design. There, the authorities fitted sensors in 2014 that send out alerts when a sheen of water is detected between the ice and the cable.

The monitors allow officials to swiftly shut off lanes when needed and then reopen them swiftly.

Jack Cousens, head of roads policy for the AA, said: ‘Despite Edinburgh being twinned with Vancouver, the technology used on Canadian bridges to keep their crossings ice-free has not been installed here.

‘Seeing as the crossing was afflicted by the same hazard last year, they have failed to zoom in on a solution.’

Ice bombs first hit the Queensferry Crossing last March when three motorists narrowly escaped injury after their vehicles were severely damaged by chunks of frozen debris falling from the cables.

Last October, Transport Scotland said it had ‘identified technology which will assist in managing the problem of ice accumulation and this is being deployed on the Queensferry Crossing over the coming months’. But in the wake of this week’s closure, the agency admitted that it still had not ordered the ice sensors.

Scottish Labour transport spokesman Colin Smyth said: ‘As usual, this has been a catalogue of broken promises by the SNP and its hard-pressed commuters who are paying the price of their incompetence.’