Failures of sewer systems were once thought to be unavoidable and systems were operated on a reactive basis. Unfortunately this approach meant that pollution and flooding incidents were unavoidable. WRc's Sewer Operations team have been at the forefront to challenge this view in recent years. We have shown that the numbers of failures can be reduced dramatically by improved workmanship and taking a more proactive approach to sewer operations. Our approach involves developing a detailed understanding of the mechanisms and causes of failures, and the mechanisms that lead to flooding and pollution impacts. This has included work on the management of sewer blockages, sewer infiltration, sewage pumping stations, street ironworks failures, and sewer inspection methods. To reduce blockages we have undertaken research into the effects of Fats Oils and Grease (FOG), food waste and so called flushable products and we continue to work on measures to limit their impact.