This map provides near real-time information about storm overflow activity, as indicated by event duration monitoring (EDM). You can use the map to see if the EDM monitors indicate: i. that overflows are currently discharging into a watercourse Ii. the date and time of the last recorded discharge. The data received from the EDM monitors isn’t always accurate. It doesn’t confirm discharges, it only indicates them. Thames Water is being open and sharing that data exactly as it receives it, so you can make more informed decisions.