CLACKS commuters could face delays this month with M90 traffic set to be diverted over the Forth Road Bridge.

From 10pm on Saturday, December 11, traffic will be diverted in a trial of measures designed to speed up the process if the Queensferry Crossing needs to be closed.

Southbound traffic on the M90 will be diverted off the motorway at Junction 1B Ferrytoll, before crossing the Ferrytoll Roundabout and joining the Forth Road Bridge via the A9000, which is normally reserved for public transport.

During this diversion there will be no access to the Ferrytoll Roundabout eastbound from the B981 or westbound from Hope Street, Inverkeithing.

Local traffic will be required to access the M90 via Junction 1C Admiralty.

The Queensferry Crossing will be reopened by 6am on Sunday, December 12 at the latest.

Chris Tracey, BEAR Scotland’s unit bridges manager for South East Scotland, said: “Earlier this year we trialled a full diversion via Forth Road Bridge using the emergency links north and south of the bridge.

“This proved effective once open, but took over five hours to implement, with traffic diverted via Kincardine in the meantime.

“Last winter’s two closures of the Queensferry Crossing only lasted for a few hours, so there wasn’t time to fully implement this option.

“The purpose of next weekend’s trial is to test how long it takes to implement a diversion using the slip roads on either side of the bridge.

“This would not provide the same capacity but could reduce the need for all traffic to divert via Kincardine if it can be done quickly.

“For longer term closures we would still open the emergency links north and south of the bridge to maximise capacity.

“If this trial proves successful, then further trials and modelling will be required to test the impact on traffic before incorporating it into our procedures.

“We are also investigating other ways of speeding up the diversion process, such as barriers that can be opened automatically.”