SZC related Traffic Management & Road Closure

See below for Sizewell C current and up and coming road closures and traffic management.

Road Closures

Willow Marsh Lane, Darsham is closed until June 2026 to enable the construction of the Northern Park & Ride roundabout and site. Diversion in place via Walpole Road, A144, A12.

Abbey Lane, Leiston is closed until January 2027 to enable the construction of the new railway line. Diversions in place via Harrow Lane, Hawthorn Road and Pretty Road.

Night-time closure along Lovers Lane and Valley Road from the 22 October to 20 December 20:00 – 05:00. This to enable the installation of power cables. With daytime 2-way traffic lights in place. Diversion via B1122 and King George’s Avenue.

Church Road, Theberton is closed between 6 and 31 October by Scottish Power to carry out Sizewell C and Scottish Power combined mitigation scheme at Theberton.

Kettles Lane, Benhall is closed until June 2026 for the construction of the Friday Street roundabout.

Fordley Road, Middleton will be closed from 3 to 14 November for Openreach to undertake diversion works.

Littlemoor Road, Middleton will be closed from 17 November 2025 and is not expected to be reopened.

Night-time closure of the A12 and the A1094 from 3 to 8 November 2025 between the hours of 20:00 – 05:00. Table below shows the phases of the closure.

Diversions will be in place:

• The A12 northbound diversion route will be B1116; A1120; A12 and vice versa.
• The A12 southbound diversion route will be B1122, B1069, A1094, B1069, A1152.
• The A1094 diversion route will be B1122, B1069, A1094, B1069, A1152, A12 and vice versa.

Closures of A140 and B1078 to facilitate the delivery of Sizewell C road safety mitigation scheme.

Overnight road closure of the A12 Northbound to allow white lining & removal of temporary road studs and other traffic management associated with the AIL Layby works from 5 to 6 December between the hours of 20:00 - 05:00.

Traffic Management

A12 single lane closure northbound along the dual carriage way from Ufford Road to the Wickham Market Slip Road. Expected to be in place till 20 December 2025.

A12, Friday Street varying traffic management in place, including lane closures and traffic signals until June 2026 as part of construction of the new roundabout.

B1122 off peak traffic signals implemented by Scottish Power at Theberton to deliver improved pedestrian footway 22 September to 31 October.

Sizewell C is also currently implementing short term nighttime traffic management associated with the delivery of the Sizewell C countywide highway signs throughout the month.

Two-way traffic lights on the A12 north of Town Farm Lane. This will be in place from 3 November – 21 November 2025. This is to enable Cadent Gas to carry out essential works to divert a Gas Mains.

Scottish Power Renewables will have two sets of two-way traffic lights on Sizewell Gap Road from 13 October for approx. eight weeks. These lights will be in operation between the hours of

A12 slip road next to the Southern Park Ride site, traffic lights in use to ensure safe working zone for construction of the site entrance works. This will be in place until 12 December 2025.

Two-way traffic lights on the A12, in the vicinity of Tinkerbrook Brook Lane. This will be in place from 27 October - 7 November, between the hours of 09:30 -15:50.

Traffic lights on A12 north and B1122 Middleton Road on nights for construction of new road and kerb alignment for the Yoxford roundabout from 3 to 18 December between the hours of 19:00 -05:00.

2-way traffic lights on the A12 southbound at Friday Street on nights to undertake excavation in the verges, 19 to 21 November between the hours of 20:00 - to 05:00.

Speed restrictions

A12 between Glemham and Benhall, 30 mph speed limit in place whilst works are carried out to construct the new by-pass.

A12 Friday Street 30 mph speed limit in place whilst works are carried out to construct the new roundabout.

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

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

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

B1125, 30mph and 50mph speed limits in place associated with speed cameras.

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

30 mph speed restrictions on Eastbridge Road until October 2026.