The Werrington Dive Under (known as the Werrington Grade Separation during construction)[1] is a replacement dual track grade separated railway junction at Werrington Junction, 3 miles (5 km) north of Peterborough railway station in Cambridgeshire, England. The junction leads to the Great Northern/Great Eastern Joint line (GN/GE) which goes through Spalding to Lincoln and beyond. Completed and opened in December 2021,[2] the dive under allows trains on the west side of the East Coast Main Line (ECML) to access the GN/GE line without conflicting with the faster passenger services on the ECML.
The dive under was constructed by a 'jacked deck' on slide paths installed in access tunnels. The curved 'jack deck', pushed into place beneath the main running lines, will be the first use of such a structure in the United Kingdom. The installation uses a patented method of construction.