Sizewell C related Traffic Management, Road Closures & Rail Movements

Please see below for the current and up and coming train movements, road closures and traffic management in relation to the Sizewell C project:

See below for current and up and coming freight train movements, road closures and traffic management in relation to the Sizewell C project:

Freight Train Movements

No planned train movements the week commencing 14 September 2026.

A12 Closures

Marlesford

The A12 at Marlesford will be closed at weeknights (8pm-5am) from 8pm 21 Sept to 5am Saturday 3 October. The diversion route is A1152, B1069, A1094 and vice versa.

Darsham

The A12 at Darsham will be closed at weeknights (8pm-5am) from 7-18 September and 5-16 October for works associated with a new pedestrian crossing.  Due to impacts of other A12 closures, further dates will be required, which we are currently coordinating, but dates are to be confirmed.  The diversion route is A12, A14, A140, A143, A12 and vice versa.

Wickham Market

A12 northbound off-slip at Wickham Market will be closed nighttime (8pm to 5am) 16 September to 5am 19 September for installing signs associated with the southern Park and Ride.

B1122 Closures

Leiston

From 27 July to 20 September, Abbey Road (B1122) will be closed 24/7 at the Leiston level crossing. The extension of the closure into September is due to complications related to the location of utilities. The eastern end of Westward Ho will also be closed for approximately 80 metres from the junction with Abbey Road.  Pedestrian access will be maintained.

The diversion route is B1122, A12, A1094, B1069, B1122.

B1122 will be closed Monday to Thursday weeknights from Yoxford roundabout to approximately 50M past Title Road Yoxford from 21 September to 6 November for coordinated works associated with the B1122 Early Years scheme and Sizewell Link Road. Access to properties located within the closure and between closure points will be maintained throughout.

There will be weekend closures of the B1122 between Potters Street and Rowley Mews, Eastbridge Road from the B1122 for approximately 300m, and Lovers Lane from the B1122 to King George’s Avenue, Leiston, throughout September, October and November, with a targeted start date of the weekends of 8pm 25 September to 5am 28 September and 8pm 2 October to 5am 5 October.

We will continue to provide updates on the works tracker including more specific details when they are available.

Other Road Closures

Leiston and Theberton

George Road is closed from 26 May to September 2028 for works associated with the Sizewell Link Road. The diversion route will be Harrow Lane, Abbey Lane and B1122.

Pretty Road will be closed until Q3 2027 for the construction of an overbridge as part of the Sizewell Link Road. The diversion route will be Harrow Lane, Abbey Lane and B1122.

Hawthorn Road will be closed from 10 August 2026 to 30 April 2027 for the construction of the Sizewell Link Road. The diversion route will be Harrow Lane, Abbey Lane and B1122.

Middleton-cum-Fordley

Fordley Road will be closed from 10 August 2026 until Q3 2027 for the construction of the Sizewell Link Road. The diversion route will be Fordley Road, Town Farm Lane, A12, and B1122.

Littlemoor Road, Middleton, has been closed from 19 November 2025 and is not expected to be reopened.

Farnham

Hill Farm Road has been fully closed from 12 January 2026 for works associated with the two-village bypass. The diversion route is A12, A1094 and Botany Farm Lane and vice versa.

Marlesford – local roads

Bell Lane will be closed (7pm to 5am) to the 1 October for approximately 100 metres from its junction with the A12.Tthe diversion route will be Keeper’s Lane and A12.

Ashe Road (south of the A12, aka Marlesford Road) will be closed (7pm to 5am) for approx. 130 metres from the A12 junction from 27 July to 19 September. The diversion route will be Hacheston Road, B1078 and vice versa.

Marlesford Road will be fully closed for approx. 130 metres from the A12 junction from 19 September to 5 October. The diversion route will be Marlesford Road, B1116, A12.

A1094 / B1069

Scottish Power Renewables will close the A1094 / B1069 between 9 November to the 18 December on weeknights (8pm to 6am) to undertake the coordinated improvement scheme with Sizewell C.

Non-Sizewell C Road Closure

Essex and Suffolk Water are closing the B1125 from 9 November 2026 to 1 March 2027 for a renewal scheme. Sizewell C are looking at collaboration with these works and will provide updates when available.

Traffic Management

Leiston

Ongoing traffic signals on Lover’s Lane and B1122 Abbey Road.

Ongoing traffic signals on Buckleswood Road associated with the rail crossing.

Sizewell C is undertaking cleaning of the highway under temporary traffic management between B1122 and Eastbridge during the weeks of 14 and 21 September 2026.

Speed restrictions

A12 between Kelsale and Yoxford: a 30mph speed limit in place whilst works are carried out to construct the Sizewell Link Road and roundabout.

A12 Darsham: a 30mph speed limit in place whilst works are carried out to construct the Northern Park & Ride roundabout.

B1122, Lover’s Lane and Sizewell Gap: a 30mph speed limit in place.

Buckleswood Road and Westward Ho, Leiston: 30 mph speed limits are in place whilst works are carried out to construct the Green Rail Route.

B1125: 30mph and 50mph speed limits are in place associated with the speed cameras.

Eastbridge Road: 30mph speed restrictions are in place whilst works are carried out to construct the Sizewell Link Road.

Sizewell Gap: 30mph speed limit on Sizewell Gap up to Sizewell Haul Road.