Channel 4's Dirty Business has put water quality back in the spotlight. For wingers and windsurfers, the question is simple: how do I know if it's safe to get in?
Here's the honest answer: there's no perfect system. But there are tools that can help you make informed decisions-and it's worth using more than one.
KnotNow: Water Quality in Your Forecast
We built water quality monitoring into KnotNow because we didn't want you to have to juggle separate apps. On each location's forecast page, you'll see sewage discharge alerts alongside wind, tide and weather - including the "NOW" and "ACTIVITY IN 48 HRS" cards that show current status and recent discharge events.
What we show: Real-time operational status from water company outfalls in England. Our "ACTIVITY IN 48 HRS" flags any outflow that has been active within the last 48 hours. If a sewage discharge started prior to that window and is still ongoing (or only recently stopped), the total duration shown will exceed 48 hours.
How are discharge events combined? When a location reports multiple stop-and-start events within 48 hours, we combine them into a single discharge event with a total duration. In practice, brief gaps between reported events may not mean the water was clear - the sewage overflow may have continued between those signals. We err on the side of caution and combine events to give you the fullest picture of activity at each outfall.
The general rule of thumb is to allow a 48-hour clear window after a discharge ends before hitting the water. If you're seeing high numbers, it might be a good day to check your kit or grab a coffee instead of a session.
What we don't show: Our data comes from the water companies themselves. We can only display what they report. Coverage is England only - Scotland, Wales and Northern Ireland use different monitoring systems. And we don't cover every outfall; some spots have no nearby monitoring.
We at KnotNow highlight sewage discharge events for 48 hours. This precautionary window accounts for variable dispersal times, ensuring you have the clearest possible picture of recent activity. With sewage overflowing into England's waterways more frequently than many would like, we believe transparency helps you make informed choices.
Surfers Against Sewage App
The Surfers Against Sewage Safer Seas & Rivers Service app is free and covers beaches, rivers and lakes across the UK. It draws on Environment Agency data and provides real-time pollution alerts. Many wingers use both: KnotNow for the full forecast (wind, tide, water quality in one place), SAS for broader UK coverage and river spots.
The 48-Hour Rule
After heavy rainfall, storm overflows are most likely to activate. Many experts suggest waiting at least 48 hours after a significant downpour before entering the water-especially near river mouths, where runoff concentrates.
Know Your Spot
Some locations are more vulnerable than others. Estuaries, spots downstream of sewage works, and beaches with known combined sewer overflows deserve extra caution. Use the water quality section on each KnotNow forecast to see the monitoring status for your spot.
Don't Let Them Win
As Reuben Santer said in his campaign: don't let this dirty business put you off getting in the water. Instead, empower yourself with the tools to know when it's safe. Check the forecast. Sign the petition. And keep enjoying our waters-we can't let them win.