Sewage Discharge (Dundee) Mr. Gordon Wilson asked the Secretary of State for Scotland what is the output of sewage from Dundee each day; and what effect such effluent has on the Tay. Mr. William Ross The daily discharge of sewage from Dundee is about 16 million gallons. This passes through 27 out-falls, spread over eight miles of river frontage, and although most of the sewage is at present untreated, its effects on the Tay estuary are relatively local to the discharge points. There is no evidence of any health hazard, and the ecology of the estuary does not appear to be significantly affected.