Don't paddle in the sewage: adding water-quality awareness to trip planning

In 2024, water companies made 592,478 confirmed sewage discharges into UK waters, and once under-reporting is counted, Surfers Against Sewage puts the real figure near a million, about one every 30 seconds. Five people a day reported falling ill after going in. For paddlers, water quality has become part of the plan, not an afterthought.

The pattern is predictable, which is the useful part. Most sewage spills happen during and after heavy rain. The UK's older sewers carry rainwater and sewage in the same pipes, so when a downpour overwhelms them, water companies are allowed to release untreated wastewater through combined sewer overflows. Rain also washes muck off roads and fields into rivers and the sea. The Environment Agency puts it plainly: heavy rain, high tides or strong winds make reduced water quality 'more likely'. A hot, dry week is usually a good bet; the day after a summer storm is not.

A simple rule of thumb follows from that. Surfers Against Sewage flags a sewage alert wherever there has been a confirmed discharge in the previous 48 hours, in line with the precaution that bacteria stay raised for a day or two before the water clears. So after heavy rain or a known spill, give it around 48 hours before you paddle somewhere you might fall in, and longer at a spot with a bad record. You do not need to stop paddling. You need to avoid a mouthful of the wrong water on the wrong day.

Water quality belongs alongside wind and temperature as something you check before you go. When you are planning a paddle, weigh the last few days of rain the way you weigh the forecast. And when you learn that a particular outfall or stretch has a habit of going bad after rain, mark it. A hazard pin in PaddleScout records it on the map, and shared with your paddling friends it warns them too, the same way you would flag a weir or an offshore-exposed beach. We cover that side of it in our post on mapping hazards. The cleanest water, like the calmest wind, is usually a decision you make before you leave the house.