Glasgow M8 roadworks to remain for another two years after 'challenges' cause delays

Roadworks on a section of the M8 will continue for another two years after unforeseen “challenges” caused significant delays.

Temporary propping of the motorway at the Woodside Viaducts in Glasgow began in March 2021 after the bridges’ supports were found to be in worse condition than expected.

Now, work on the eastbound carriageway won’t be finished until Autumn 2026, while completion on the westbound carriageway isn’t scheduled until the second half of 2027.

The estimated cost of these initial works is as high as £152m.

The date for completing the temporary repair to the Woodside Viaduct has been pushed back again. Transport Scotland

Amey, undertaking work on behalf of Transport Scotland, said it is working to overcome “previously unknown challenges” at the site, along with ongoing work to control previously known risks.

The revised completion dates remain subject to “no further adverse conditions or unforeseen challenges”.

Lane restrictions on the motorway’s eastbound carriageway were due to be lifted early this summer, with the westbound to follow early in 2026.

The discovery of a sewer in an unexpected location next to a Glasgow subway tunnel was said to be the most significant issue engineers encountered.

When STV News visited the site in November 2024, temporary props had been installed at 13 locations out of 23. No additional props has been put in place since.

However, two more props have been jacked up to assist with supporting the motorway and taking the load.

M8 Roadworks: Timeline of expected six-year delays

March 2021 – Ahead of planned refurbishment work, intrusive inspections of the supports were completed and found the viaduct crossheads to be in a much worse condition than anticipated, requiring the implementation of traffic management to reduce the load on the viaducts
February 2022 – Propping completion projected as November 2023
February 2023 – Propping completion projected as late 2024
May 2024 – Transport Scotland updated on the progress and the challenging picture that had emerged of the complex work area within which the Contractor was working. An estimated cost range of £126m-£152m and propping completion in early 2026 with the eastbound carriageway sooner in summer 2025 was published

November 2024 – Transport bosses tell STV News that the roadworks are the “biggest on their books” after three-and-a-half years of delays
August 2025 – As a result of previously identified risks and the discovery of a conflicting sewer, timescales have been revised to the second half of 2027 with the contractor working to open the eastbound carriageway in Autumn 2026

What do the current works involve?

Inspections in 2020 found the condition of the motorway bridges’ supports to be worse than expected.

The works include strengthening the triangular crossheads, which support the viaducts at their western end, and the associated propping steelwork.

Since November 2024, progress on the temporary propping has slowed, with only two new props jacked. Transport Scotland

Transport Scotland said both of those elements have been “more complicated than anticipated”.

They say the need to avoid loading the Subway tunnels has introduced an “unusual level of complexity” and has resulted in delays to propping both the viaducts.

An existing sewer, adjacent to the Subway tunnel at the western end of the viaducts, was found to be in a different location than expected.

Since November 2024, progress on the temporary propping has slowed, with only two new props jacked.

Transport Scotland initially hoped to lift lane restrictions in early summer 2025, but this has been pushed back.

Why are the works taking so long?

Transport Scotland’s director of major projects, Lawrence Shackman, admitted the project had been “continuously hampered by inaccurate records of utility apparatus”.

He also said the recent discovery of a sewer buried deep underground has led to delays and additional work.

Mr Shackman said: “I understand the completion of these works is keenly anticipated by M8 road users and the local community, not least to lessen the impacts from its construction.

“I’d like to thank everyone for their patience and understanding to date and assure them that Transport Scotland continues to robustly engage with the contractor, Amey, to deliver the work as quickly and safely as possible, whilst keeping the motorway open to the 150,000 vehicles who use it daily.

“Despite facing significant challenges, the project has made substantial progress with temporary props installed at 13 pier locations out of 23.

“In addition, ten of the temporary props have been jacked to assist with supporting the carriageway and taking the load.

“The location of the motorway through a busy, built-up city has meant this project has always been technically complex and presented a number of challenges, notwithstanding dealing with 23 supports that all require individual propping designs to take account of the varying column heights, span lengths and widths.

“Amey continues to face significant challenges, and the latest information now indicates an anticipated date for full completion of the work allowing traffic management to be removed in the second half of 2027.

“Due to the nature of the work, they are continuing to work towards opening the Eastbound carriageway in Autumn 2026.”