Launched in 2023, a live map of sewage treatment works’ Event Duration Monitors (EDMs) shows where spills are occurring across the Thames Water region. The upper Ver Valley is affected by spills into the Ver at Markyate and at Caddington spills discharge to a borehole. Sewage waste from Flamstead south, including from St Albans, mostly goes to Maple Lodge near Rickmansworth for processing. Any spills here are discharged into the Grand Union Canal/Colne – check the map for these three sites in particular.
