Deephams   
Deephams Sewage Works in the London Borough of Enfield (the orange blob on the map) usually handles 209,000 cubic metres of sewage every day. The Environment Agency requires the treated wastewater to flow into Salmon's Brook , which according to Wikipedia rises in Enfield Chase, runs past Deephams and the Edmonton incinerator, through to Pymmes Brook, a tributary that joins the Lea at Tottenham. See polluted Lea.

Work on Deephams is due to start in 2015 and may last last until 2020/21.(13/July/2012)
Click to see the story behind Deephams and SUDS
Lea Marshes