Concerns about public health led to the construction between 1876 and 1904 of three separate sewer systems to serve metropolitan Boston.

出于对公众健康的担忧，1876年至1904年期间，为了服务于波士顿市区，政府修建了三个独立的下水道系统。

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The discharges from separate storm sewer systems in the dry weather do great harm to receiving water in Shanghai.

分流制雨水系统旱流放江严重污染了上海市河道水质。

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During her five-day cruise, a water line broke in the hallway ceiling near her cabin, and a separate sewer line broke outside the main dining hall, she said.

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The tunnels merge and separate, feed into the sewer system, and branch out again for hundreds of metres, emerging right outside town, amid the bushes of a dry river bed.

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