Technically, yes. People do it. There’s an annual race called the Great London Swim. They jump right in.
But here’s the catch: the water is safe from natural nasties. The big problem is storm overflow. When it rains hard, old sewers dump raw waste into the river.
So, after a downpour? Don’t touch it. On a sunny day? It’s mostly fine. You just end up looking like a chocolate bar.
The Physics of a Brown River
Think of the Thames as a giant blender. The tide pushes one way, fresh river water pushes the other. They meet in London, right under the Houses of Parliament.
Why Is the River Thames Brown? The Surprising Truth - YouTube
This is the "tidal limit." It’s where the river gets really confused. All that energy keeps the mud suspended. It never settles.
The mud is so fine, it’s like flour. It doesn’t sink quickly. It just hangs around, giving the river its signature murk.
