The River Westbourne rises in Hampstead Heath and was incorporated in Bazalgette's sewerage system as the Ranelagh Sewer.
The Egg is a Victorian storm relief sewer that serves both the River Tyburn (KSP sewer) and the Westbourne (Ranelagh sewer).
Averaging around 5 1/2ft, this brick and concrete drain appears to act as a relief sewer.
This large box shaped CSO tank serves a 5ft sewer and outfalls to the Medlock in the East of Manchester.
One of the many culverts that makes up the Hockley Brook as it travels under Birmingham.
A look at some of the outfalls after a storm near Ringley treatment works.
Big Humpty takes the River Medlock through a short but large egg shaped culvert.