Sewer overflows: proposed Thames Tideway Tunnel – DEFRA

July 16, 2012

From 16 July 2012, the Thames Tunnel was formally renamed the Thames Tideway Tunnel.  References to the Thames Tunnel in relevant Defra web pages, including this one, have been amended accordingly, but linked documents that pre-date 16 July 2012 remain unaltered.

Combined sewerage systems are so called because rainwater run-off is combined with domestic and industrial sewage and transported to sewage treatment works.