They start in our wastewater, then flow into rivers and out to the sea, where they are eaten by sea animals.

首先是我们的废水，接着便流入河海，被海里的动物吞食。

youdao

Rivers flow into the sea.

江河流入海中。

《新英汉大辞典》

All rivers flow into the sea.

百川归海。

《新英汉大辞典》

Next, Hawaii Volcanoes National Park offers spectacular hiking and, if you are lucky, a chance to watch live lava flow into the sea.

BBC: How to choose a Hawaiian island

At low tide, water would flow from the lagoon into the sea, and from the sea into the lagoon at high tide.

BBC: An artist's impression of how the lagoon could look

More importantly, some scientists are concerned that the flow of desalinated water into the sea could disrupt the Gulf Stream, which could change weather patterns.

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