Project Update – November 2025

Welcome to the latest round up of construction activity at Sizewell C.  Our SMS alert service is now live.  Anyone can sign up to receive works tracker updates via SMS as well as email. Click here to subscribe Sizewell C Works Tracker - Track SZC Projects & Get Alerts for New Activities via the login button.

Thank you for your patience as work continues to build the new infrastructure required such as park and ride facilities to bus our workers into site and improvements such as the A12 two village bypass and Sizewell Link Road.  We are sorry for the inconvenience our works are causing.  The Sizewell C works tracker and One Network Causeway one.network are guides to works in the area and the new subscription service through our works tracker will also help with transport plans around the county.

We continue to work across the county to improve Sizewell C related road signs, which includes removing temporary signs and replacing with permanent road signs. This will ensure contract drivers are taking the correct routes.  Closer to site, we are also replacing temporary road signs along the B1122 with permanent speed reduction and camera signs.

We are in the final stages of the widened and improved layby on the A12 to assist police escorting our wide load HGVs. Working closely with Suffolk County Council, as road users are aware, we have closed one of the lanes of the dual carriageway. This is to ensure traffic flow and not create a bottleneck along the dual carriageway by ensuring a consistent one lane traffic flow from Woodbridge. This also ensures road safety for road users and workers, and Suffolk County Council will also be undertaking maintenance work during this time. The traffic management will be in place until December.

Temporary Construction Area (TCA)

On the Temporary Construction Area we have almost finished the installation of the foundations for our water desalination plant. Our main access road on the site is operational, and we are continuing to install utilities ready for our worker welfare facilities.

The foundations for the concrete batching plant, which will serve Sizewell C throughout construction, are also being poured. Having a plant on site is much more efficient than transporting concrete from off-site, helping to further reduce the number of HGVs on the roads.

The rail line into the TCA (Green Rail Route) is also being prepared with earth being removed in preparation for the laying of tracks.

Beach and Harbour Area

The construction of the northern section of the temporary sea defence is continuing with sheet piles being installed.  These interlocking steel sheets will create a continuous retaining wall that provides excavation support. Our earthworks team continue to backfill the area ahead of the next phase of the work for the Combined Discharge Outfall drainage system.

The construction of the collar at the top of the shaft that will take seawater to the desalination plant continues on the foreshore ahead of the excavation of the 26-metre deep shaft.

In and around Leiston

The site where the plaza roundabout will be built continues to be prepared for construction.   Over the coming months there will be further traffic management and road closures as we build a rail level crossing over Abbey Road.  The first phase of these works has been completed with a temporary road being installed that links the B1122 to Lovers Lane and then back onto the B1122 / Abbey Road. All road users will be required to use this temporary diversion whilst the new level crossing is constructed.

The works in Theberton on Church Lane are being carried out by Scottish Power Renewables and are due to be completed on 21 November.

We hope you have been able to use the new bikes around the town which are part of the  “Pedal to Zero” cycling scheme. The locations where bikes can be used from include the East of England Co-op, Leiston Town Council Office, Leiston Community Centre, The Waterloo Centre and Leiston Leisure Centre.

Community Road Improvements

From mid-November we will start to make road improvements along the B1078. The overall improvements are between the A140 junction with the B1078 and Wickham Market and include new signs, village gateway signs, improvements to visibility at junctions and areas of carriageway resurfacing. The work will be carried out at night, and diversions will be in place where it has been necessary to close the road.

Two Village Bypass and Friday Street Roundabout

We have now completed the archaeology along the Two Village Bypass, tree and ecology clearance and access works at Tinker Brook have also finished.  The construction of the Friday Street roundabout is ongoing, with the aim to open the roundabout to traffic in the summer of 2026. There is significant traffic management along the A12 as we carry out these works which are continuously reviewed, checked and maintained.

Sizewell Link Road

Galliford Try, the main contractors for Sizewell Link Road have started work on site.  Initial works include establishing a compound for worker welfare and equipment, as well as constructing a haul road, setting up temporary fencing and the diversion and upgrade of underground utilities are ongoing.  This will require traffic management along the A12 with two-way lights.

Yoxford Roundabout

Works at Yoxford Roundabout remain on track to open in the spring of 2026. Vegetation and ecology surveys have been completed allowing for utility diversions to take place. This will require traffic management along the A12 and the B1122 as works are carried out safely. Further details are outlined on the Sizewell C works tracker website.

Park and Rides

Northern Park and Ride, Darsham

Our contractor, Galldris, continues to build the new roundabout off-line from the A12 while keeping works and disruption on the carriageway to a minimum. However, traffic management (two-way traffic lights) are in place for the roundabout to be connected to the A12.  A phased operation of the park and ride site has commenced with spaces available for 100 vehicles and a bus service has now started.

Southern Park and Ride, Wickham Market

Galldris also continue work on the Southern Park and Ride, including earthworks and the construction of their compound. Works on the entrance to the Park and Ride continue off the slip road. A phased operation of the park and ride site will start towards the end of this year.

Essex and Suffolk water and Cadent gas continue to divert and upgrade the underground utilities in the area. The works will at times require temporary traffic lights along the A12.

Rail Works

In October track upgrades began to the east of Summerhill level crossing and work has commenced on the Leiston Level Crossing on Abbey Road.  This will involve traffic management and road closures; further details will be outlined in due course. Buckleswood Road in Leiston will be closed from 17 November until 31 January 2026 to construct the level crossing, across the road and install drainage systems. Diversions are outlined on the Suffolk onenetwork.com website.

The archaeology along the Green Rail Route (GRR) is complete and the site has been handed over to the earthworks contractor, which have begun digging the rail route.  Installation of the tracks will shortly follow, once this phase is complete.

Our rail team is working on installing railheads at the Ancillary Construction Area and Temporary Construction Area.  Further information can be found on our Works Tracker here: Rail Replacement Works - Sizewell C Works Tracker