Road closures planned for essential works on the A6

23 April 2026

North Northamptonshire Council is advising motorists of essential roadworks taking place at along the A6 at Irthlingborough viaduct next month, which will require full weekend road closures to allow critical maintenance to be carried out safely.

The works are Phase 1 of a programme to re-waterproof a section of Irthlingborough viaduct.

To minimise disruption, the works have been scheduled over the weekend:

• Full Closure from Friday 8 May 2026, 8pm – Monday 11 May 2026, 6am
• Overnight Closure Monday 11 May 2026, 8pm – Tuesday 12 May 2026, 6am

Phase 2 will take place from Friday 29 May:

• Full Closure from Friday 29 May 2026, 8pm - Monday 1 June 2026, 6am
• Overnight Closure Monday 1 June, 8pm - Tuesday 2 June, 6am

This work is the start of phased re-waterproofing and expansion joint replacement of the reinforced concrete viaduct.

The viaduct was constructed in 1936 and is in relatively good condition but needs major works to preserve its integrity and ensure it is fully functional for many years to come.

Whilst work will be required for all 9 decks over the coming years, deck 7 is the priority as it has had repeated occurrences of damaging potholes developing. The scheme has been funded by the Local Transport Grant, received from the Department for Transport.

During the closure, contractors will remove the existing surfacing and waterproofing from the bridge deck, carry out concrete repairs where required, and apply a new spray applied waterproofing system. This process is weather dependent and must take place in dry conditions, followed by integrity testing before the carriageway surface and road markings can be reinstated.

We understand that full weekend road closures can be inconvenient, but these works are essential to protect the long term safety and integrity of the Irthlingborough Viaduct. By carrying out the majority of works over a weekend, we are significantly reducing disruption to weekday traffic, commuters, and local businesses.

I would like to thank residents and road users for their patience while these important improvements are completed.Cllr Chris McGiffen, Executive Member for Highways and Travel at North Northamptonshire Council

Signed diversion routes will be in place during closures and motorists are advised to follow local diversion signage, plan journeys in advance and allow extra time for travel.

A contingency weekend has been identified should the works be affected by adverse weather:

• Full Closure (Contingency) Friday 15 May 2026, 8pm – Monday 18 May 2026, 6am
• Overnight Closure Monday 18 May 2026, 8pm – Tuesday 19 May 2026, 6am

Phase 2 contingency dates:

• Full Closure (Contingency) Friday 5 June 8pm - Monday 8 June, 6am 
• Overnight Closure Monday 8 June, 8pm - Tuesday 9 June, 6am

Any changes to works will be published on the North Northants Highways Facebook page.

Further information about roadworks in North Northamptonshire is available on the council website.