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Choose a swim spot
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What lies upstream
rivers within 60 km along the network…
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Overflow by overflow
ordered by the model's weight at this spot4
The questions the research is testing
results as recorded, adopted and failed alike5
What it cannot tell you
- No spill was followed down a river. The lines are the mapped rivers that join each overflow to the spot. Travel times and weights are the model's settings, fitted to samples, not measured journeys.
- The clock is an illustration. It shows when water would arrive at the model's assumed speed. Real speed changes with flow: a river in flood moves far faster than one in a dry spell.
- Monitored overflows only. Farms, misconnected drains, birds, dogs and unmonitored outfalls also carry bacteria. A spot with no overflow upstream is not a clean spot.
- Sixty kilometres is a cut-off, not a boundary. Overflows further up are left out because the model gives them almost no weight, not because their water never arrives.
- A lake is not a pipe. At lakes the model holds water for the lake's residence time and mixes it. Wind and currents can carry a plume much faster along one shore.
- Official advice comes first. Environment Agency notices and signs at the water are shown on each spot page.
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