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Green Means Clean: Assessing the Condition of U.S. Drinking Water Watersheds

This article is from Issue Freshwater - Vol. 18 No. 1.

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With 2/3 of the U.S. population drinking water from surface sources such as streams, rivers, lakes, and reservoirs it is very important that these water sources are protected.  Part of protecting the water sources and providing cleaner water is protecting the natural land within the watershed. Watershed boundaries often cross State lines. The scientists in this study were interested in conducting a national assessment of drinking water watersheds that crossed State boundaries. 

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Reflection Section Answer Guide

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Additional Resources for this Article:
Meet the scientists that contributed to this article:

"Thinking About Science Themes" covered in this article:
Look at the section entitled, What Kinds of Scientists Did This Research? What do you notice about the kinds of scientists who are involved with this study? You probably noticed that three different kinds of scientists worked together to study drinking water watersheds in the United States. You might have also noticed that two of the scientists study relationships. When different kinds of scientists come together to conduct a study, each scientist brings a different perspective, a different kind of knowledge, and perhaps different scientific methods. These differences strengthen the study. One person may see or understand things that another person may not. If you are holding a hard copy of Natural Inquirer, take a moment to look at the What Kinds of Scientists Did This Research? section of the other articles within the journal. You may also look at this section in more articles by viewing Natural IQ: Southern United States Climate Change edition at http://www.naturalinquirer. org. Notice that a variety of scientists came together to conduct the other studies. Relate this characteristic of scientific research to your own experiences. Share an experience of when having many different perspectives was an advantage for you.
Specific "Thinking About Science" Themes:
  • Characteristics of Scientists

"Thinking About Environmental Themes" covered in this article:
A watershed is an area of land where all the water that is underground within the area and all the water that drains off of its surface goes to the same place (figure 1). Watersheds contain streams or rivers that carry surface water toward the oceans, and they may contain lakes or reservoirs (re zə vwrz) (figures 2a and 2b). Watersheds hold groundwater, which also flows into streams and rivers. In the United States, the largest watersheds are defined by the Continental Divide (figure 3). One of these large watersheds drains into the Pacific Ocean. The other large watershed drains into the Atlantic Ocean, the Gulf of Mexico, and the Caribbean Sea. Smaller watersheds are contained within each larger watershed in a nesting pattern (figure 4).
Specific "Thinking About the Environment" Themes:
  • Water
  • Water Resources

NSE Standards covered in this article:
  • Abilities necessary to do scientific inquiry (A)
  • Nature of science (G)
  • Populations, resources and environments (F)
  • Risks and benefits (F)
  • Science as a human endeavor (G)
  • Structure of the earth system (D)
  • Understandings about science and technology (E)
  • Understandings about scientific inquiry (A)