Sizewell C's three offshore utility lines are under construction

Published scope and current milestone

The current harbour register keeps Notice 11 active and lists the CDO and desalination pipe-pull notices as inactive. Notice 11 started sequential boring and lining across all three lines. Notice 19 scheduled the CDO pull around 16 April. Notice 24 scheduled the desalination intake and outfall pulls around 3 June using approximately 500-metre floating pipes, NP497, C-Odyssey and supporting vessels. The harbour programme continues through pipe installation and head structures. Planning documents provide assessment-stage head locations, while Sizewell C's water page says the temporary plant will meet most construction demand. Head installation, testing, acceptance and first production water remain unpublished.

Marine-system delivery and operating implications

Physical delivery is under way rather than confined to concept development. The desalination operation required two approximately 500-metre floating pipes, jack-up barge NP497, C-Odyssey on a four-point mooring, guard vessels and diving. The same offshore corridor also carries the CDO, while permanent cooling-water works remain a different scope.