ISBN: 1 84057 865 3
Published Date: 14/01/2019
Many Wastewater Treatment Works (WwTW) have MCERTS flow monitoring equipment at the works outlet only, which poses difficulties for assessing compliance with discharge permit conditions for Flow to Full Treatment (FFT).
We investigated the range of measurement arrangements currently in use, and their implications for FFT compliance assessment. Water companies and Regulators were consulted on their views regarding the potential (and need) for alternative FFT compliance assessment methods.
Two alternative methods (driven by flow and EDM data) were developed and applied. Approach 1 involved comparing durations of storm weir spill events and durations for which associated effluent flows exceed a FFT consent threshold. Approach 2 involved determining the level at which effluent flow reaches a plateau during storm weir spill events.
The feasibility of using static flow surveys to determine FFT compliance is also discussed.