Section outline

  • A dripping faucet showing a single drop of water, highlighting water conservation issues.

    Do we have an infinite supply of drinkable water?
    ::我们有无限的饮用水供应吗?

    No. In fact, in many parts of the world, finding clean drinkable water is difficult. This can lead to various serious health issues. Hundreds of millions of people world-wide are thought to live in areas where obtaining safe water is difficult. This makes preserving water resources an important global issue.
    ::事实上,在世界许多地方,很难找到干净的饮用水,这可能导致各种严重的健康问题,全世界数亿人被认为生活在难以获得安全饮水的地区,因此保护水资源是一个重要的全球性问题。

    Preserving Water Sources
    ::保护水源

    It might seem like there is plenty of water on Earth, but that's not really the case. Water is a limited resource . That means that it is used faster than it is replaced. Theoretically, at some point in time, the supply of fresh water could run out. Though this is unlikely, it is possible. But it is a significant issue in parts of the world with large . As these populations continue to grow, the supply of water becomes an increasingly important issue.
    ::地球上似乎有丰富的水,但情况并非如此。水是一种有限的资源。这意味着水的使用速度比被取代的速度要快。理论上,在某个时候,淡水的供应可能耗尽。虽然这不可能,但有可能。但在世界上人口众多的地区,这是一个重要的问题。随着这些人口的继续增长,水的供应变得日益重要。

    Even though we have lots of water in our oceans, we cannot use that water whenever we want. It takes special equipment, such as a desalination plant, and a lot of energy (and money) to convert salt water into fresh water. Of all the water on Earth, only about 1% can be used for drinking water. Almost all of the rest of the water is either salt water in the ocean or ice in glaciers and ice caps. As a result, there are water shortages many places in the world. Since we have such a limited supply of water, it is important to preserve our water supplies. Therefore, steps have been taken to prevent . Technologies have also been developed to conserve water and prevent water pollution .
    ::尽管我们海洋中有许多水,但我们不能随时使用这些水。它需要特殊设备,如海水淡化厂,以及大量能源(和金钱)将盐水转化为淡水。在地球上的所有水中,只有大约1%可以用于饮用水。几乎所有其余的水都是海水中的盐水,或者冰川中的冰和冰盖。因此,世界上有许多地方缺水。由于水供应如此有限,必须保护我们的供水。因此,已经采取措施防止。还开发了节水和防止水污染的技术。

    Sub-Saharan African countries have the most vulnerable water supplies. Some scientists believe of a potential future crisis in both Asia and Africa from pollution and depletion of natural water resources. Many countries in the Middle East are at an extreme risk of water shortages. Diminished water supplies could increase the risk of both internal conflicts or wars between countries.
    ::撒哈拉以南非洲国家拥有最脆弱的水供应,一些科学家认为亚洲和非洲今后都可能面临污染和自然水资源耗竭造成的危机,中东许多国家面临水短缺的极端危险,水供应的减少可能增加国内冲突或国家间战争的风险。

    Preventing Water Pollution
    ::防止水污染

    In the U.S., concern over water pollution has resulted in many federal laws. Some of these laws go all the way back to the 1800s! The laws prohibit the disposal of any waste into the nation’s rivers, lakes, streams, and other bodies of water, unless a person first has a permit. Growing concern for controlling water pollutants led to the enactment of the Clean Water Act in 1972. The Clean Water Act set water quality standards. It also limits the pollution that can enter the waterways. Other countries are also actively preventing water pollution and purifying water ( Figure ).
    ::在美国,对水污染的关注导致许多联邦法律的出台。 其中有些法律追溯到1800年代。 法律禁止将任何废物丢入国家的河流、湖泊、溪流和其他水体,除非一个人先有许可证。 越来越多的人关注控制水污染物,导致1972年颁布了《清洁水法》。 《清洁水法》规定了水质标准,并限制进入水道的污染。 其他国家也在积极防止水污染和净水(图示 ) 。

    Aerial view of the Jardine Water Purification Plant in Chicago, Illinois.

    A water purification plant in Chicago, Illinois.
    ::伊利诺斯州芝加哥的一个净水厂。

    Wastewater Treatment
    ::废水处理

    Fresh water is also preserved by purifying wastewater. Wastewater is water that has been used for cleaning, washing, flushing, or manufacturing. It includes the water that goes down your shower drain and that is flushed down your toilet. Instead of dumping wastewater directly into rivers, wastewater can be purified at a water treatment plant ( Figure ). When wastewater is recycled, waterborne diseases caused by in sewage can be prevented. What are some ways you can save water in your own house?
    ::废水是指用于清洁、清洗、冲洗或制造的水,包括冲进淋浴排水管和冲进厕所的水,废水可以直接排入河流,而不能直接将废水排入河流,废水可以在水处理厂净化(图)。当废水回收时,污水中产生的水传播疾病是可以预防的。有什么办法可以节省家里的水呢?

    Overview of a wastewater treatment plant with multiple purification tanks and surrounding structures.

    Sewage treatment plant.
    ::污水处理厂。

    Summary
    ::摘要

    • The United States, as well as other countries, have passed laws to preserve water quality and prevent water pollution.
      ::美国和其他国家都通过了维护水质和防止水污染的法律。
    • In the U.S., we also preserve our freshwater sources by purifying our wastewater.
      ::在美国,我们也通过净化我们的废水来保护我们的淡水来源。

    Explore More
    ::探索更多

    Use the resource below to answer the questions that follow.
    ::利用以下资源回答以下问题。

    • What's In Our Water from USGS (7:15)
      ::我们的水里有什么来自USGS(7: 15)
    1. What kind of material can be found in our water?
      ::在我们的水里可以找到什么样的材料?
    2. What kinds of problems can algae cause to our water resources? How is algae good?
      ::藻类会给我们的水资源造成什么问题?藻类怎么好?
    3. What is turbidity?
      ::什么是易发性?
    4. How is the pH of the Clackamas River related to river flow?
      ::Crakamas河的pH与河水流有何关联?

    Review
    ::回顾

    1. Of all the water on Earth, how much can be used as drinking water?
      ::在地球上的所有水中,有多少可以用作饮用水?
    2. How has the United States government tried to preserve water sources?
      ::美国政府如何试图保护水源?
    3. Why is wastewater treatment important?
      ::为什么废水处理很重要?