The water was so clear we could see the bottom of the lake.

湖水清澈见底。

《牛津词典》

The water is so clear that you can see your reflection in it.

水清可鉴。

《新英汉大辞典》

So many zebra mussels exist in theGreat Lakes, constantly filtering water, that they've changed the waterfrom murky to clear, fiddling with the careful ecosystem balance.

五大湖存在非常多的斑马贝。 它们不断地过滤水，把混沌的水变得清澈，随意摆弄着谨慎的生态平衡。

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But even more impressive was the filtration system that theoretically keeps the water clear, so that you can actually see the fish.

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And on the whole, on the whole I would tend to agree with that, but it does seem to me, I would want to enter a caveat, I don't think it's altogether quite so easy to have clear blue water between what you might call the private and the public.

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So the connection is clear: cut down on water use and you cut down on energy use.

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