What Happens When You Flush

What Happens When You Flush? Written by Lisa Meltzer Focus Question Where does sewage go, and how is it treated?

冲水之后会发生什么？ 作者：莉萨·梅尔泽 思考问题：污水会流向哪里，又是如何处理的？

Introduction. Swoosh! You hear this sound every time you flush a toilet. But did you ever stop to wonder where everything that you flush down winds up? Getting rid of waste is often complex process. That process can stretch over or under many miles in your city or town.

引言 唰！ 每次你冲马桶，都会听到这个声音 但你有没有好奇过，冲下去的东西最终都去了哪里？ 废弃物处理通常是一个复杂的过程 在你生活的城镇里，这套流程会在地上或是地下绵延好几英里

Where does waste come from? Where does it go? Human waste is called sewage. In most homes, it is created by using the toilet, sink, or anything that makes water dirty. If all this sewage reached our drinking water, it would make it unsafe. For more than 2 billion people around the globe, waste either piles up on the land or runs into lakes and rivers. Millions of people die each year sick from drinking water that sewage has made unsafe. Sewage treatment experts are working hard to solve this problem, but it is a huge task.

污水从哪里来？ 又要到哪里去？ 人类的排泄物叫做污水 大多数家庭中，使用马桶、水槽或是任何弄脏水的行为都会产生污水 如果这些污水流入我们的饮用水源，就会让水变得无法安全饮用 全球有超过20亿人，污水要么堆积在陆地上，要么直接流入湖泊和河流 每年都有数百万人，因为饮用被污水污染的不安全水源生病去世 污水处理专家一直在努力解决这个问题，但这是一项非常艰巨的任务

Lucky for us, the sewer pipes in our homes don't just empty into our drinking water. Instead, in many cities and towns, all of this dirty water ends up in the local sewer.

幸好我们家里的污水管，不会直接把污水排进饮用水源 相反，在大多数城镇，所有污水最终都会汇入当地的污水总管

inside the treatment plant. Small sewer pipes join up to form bigger and bigger pipes. The sewage moves through this large group of pipes to a sewage treatment plant. Here, the water is cleaned. Things in the water that can make people sick are removed.

走进污水处理厂 细小的污水管汇在一起，变得越来越粗 污水顺着这些管道一路流到污水处理厂 污水会在这里得到净化 水中会让人生病的有害物质都会被清除

not all sewage treatment systems are alike. One common type cleans sewage in the following way. Step 1. A big screen, think of a giant kitchen strainer, removes large items such as rocks, sticks, and garbage. That way, they don't jam up the treatment plant's machines. Step 2. What is left over after this process is called sludge, which is thick, dirty water. The treatment plant helps bacteria grow in the sludge. These bacteria eat the sludge to break it

并不是所有的污水处理系统都一模一样 一种常见的处理系统会按以下步骤工作 第一步 一块大滤网——就像超大号的厨房滤勺——会拦下石头、树枝、垃圾这类大块杂物 这样这些杂物就不会卡住处理厂的机器了 第二步 这一步过后剩下的浓稠脏水叫做污泥 处理厂会促进污泥里的细菌生长 这些细菌会吃掉污泥，分解它