The diagram shows the flow of clean and dirty water throughout the city of Bristol. Initially, the process begins with fresh water, fit for human consumption. As soon as it is used by humans, it becomes dirty and flows to three (3) separate destinations: rivers and streams, sewage treatment plants and the ocean.
The diagram shows that rivers and streams receive a mixture of clean and dirty water. The water which has been used by humans is the dirty water and the clean water flows from sewage treatment plants. The diagram also shows that dirty water is dumped into the ocean via rivers and streams. Thus, the ocean receives an input of dirty water from rivers/streams and water used directly by humans.
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