• First phase southbound successfully completed

• Second phase northbound scheduled for 21-24 October

• Motorists warned to plan ahead and expect long delays

Refurbishment works on the southbound side of the bridge carrying the M90 motorway over the railway near Kirkliston have been successfully completed, however Transport Scotland’s operating company BEAR Scotland is warning that a second phase of similar works is scheduled on the northbound side of the bridge this weekend.

Northbound closure this weekend

The northbound M90 will be fully closed between M9 Junction 1A and M90 Junction 1 from 20:30 on the night of Friday 21 October until 06:00 on Monday 24 October.

Motorists are warned to plan ahead and expect long delays if they need to travel north on the M90 from Edinburgh or West Lothian this weekend.

The following diversion routes will be in place:

• Southbound traffic on the M9 intending to join the M90 will be directed to leave the M9 at Junction 2 Philipstoun and follow the A904 to M90 Junction 1A Queensferry.
• Northbound traffic on the M9 intending to join the M90 will be directed to leave the M9 at Junction 1 Newbridge and follow the A8, A902 Maybury Road and A90 to M90 Junction 1.

These diversion routes are expected to be highly congested. Motorists are advised to allow plenty of extra time for journeys and avoid the area if possible.

Southbound works completed

A full programme of deck refurbishment and waterproofing replacement works was completed on the southbound side of the bridge over the weekend of 14-17 October.

• Old surfacing and waterproofing were removed, so that the condition of the underlying concrete bridge deck could be assessed and areas requiring repair identified
• Damaged and decayed concrete was then removed using hydrodemolition (very high-pressure water jets) before being repaired and reinstated with new materials
• After leaving the concrete to cure and gain strength, a new waterproofing membrane was applied followed by the installation of buried expansion joints and new kerbs
• A new surfacing course was then laid, and road markings reinstated.

The nature of these works required the M90 to be fully closed southbound, with the lack of a full hard shoulder at this location preventing the work from being undertaken with single lane closures and the bridge’s proximity to the start and end of slip roads preventing the possibility of using a contraflow system of traffic management.  This resulted in significant delays to traffic, as BEAR Scotland had warned in advance, however the motorway was reopened to full capacity before 06:00 on Monday morning as planned.

Minimising the need for reactive repairs

Chris Tracey, BEAR Scotland’s South East Unit Bridges Manager, said: “We are pleased that refurbishment works on the southbound side of the bridge were completed as planned and we thank motorists for their understanding during the significant delays experienced.

“We had delayed fully refurbishing this bridge for as long as possible to avoid the disruption it would cause to road users, but due to repeated surface failures  we had to act now before the 2022/23 winter season.  On several occasions during previous winters the road has had to be closed to carry out emergency repairs – in some instances following vehicle tyres being damaged due to the failures.

“The work we’re now doing means we won’t have to return to re-waterproof this bridge for many years after we complete the northbound side next weekend.

“We always avoid closing roads wherever it is safe and practical to do so, however the specific location of this bridge and the extent of work involved is such that full carriageway closures were unavoidable. There is no crossover point on this part of the M90 spur that would allow a contraflow and there is no room to fit a crossover in.  There is also no hard shoulder at this location that would have permitted one lane of traffic to pass.

“The multiple stages of work involved, including the time required for concrete repairs to cure before new waterproofing is installed, also meant that the job could not be completed using nightshifts only, and two full weekends working were required. The works have however been scheduled to avoid the working week and key events taking place in the surrounding area such as the autumn rugby internationals at Murrayfield.

“Ahead of the upcoming second phase, we thank road users again for their patience and understanding and recommend that they plan ahead and allow plenty of extra travel time for their journeys this weekend.

“Whilst every effort will be made to ensure that the M90 is fully open to traffic on the Monday morning, the extent of concrete repairs required will not be known until the existing surfacing is removed.  These works are also highly weather dependent and so could be postponed and rearranged at short notice depending on weather forecasts.”

Consultation has taken place with all relevant stakeholders including local authorities and Police Scotland in advance of these works.

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