Transport Scotland has said it is struggling to find ways to stop ice forming on the deck of the Queensferry Crossing.
It has said, according to a report in the Daily Record, that it has reviewed bridges across the world and found most operators simply close them and wait for ice to drop off.
The work comes after drivers travelling between Edinburgh and Fife faced a long diversion earlier this month when ice and snow caused a three hour closure of the crossing.
Transport Scotland says it has not found any method or technology that would completely remove the problem of ice build-up.
Operators of Denmark’s Oresund Bridge, the Uddevalla Bridge in Sweden and the second Severn Crossing in England, and many others all experience the same problems, according to the report.
Bridge operator BEAR Scotland said a system of weather sensors meant it could monitor conditions and take action.
Director of roads Hugh Gillies said: “The better we understand the conditions that cause this issue, the greater our chances of success. A review of measure on other bridges has been undertaken to explore the options available for the Queensferry Crossing.
“As a completely successful prevention or removal methodology has not been identified, currently most operators close the bridge and wait for the ice to fall,” he said in a letter to Labour MSP Alex Rowley.
The Forth Road Bridge will be used as a short-term diversion after the replacement of expansion joints is complete. Sensors were introduced on the crossing in July, five months after eight cars were damaged by falling ice.
