Initial Publication Date: August 12, 2008

Drying of the American West


The Colorado River basin and the seven states that depend upon its water. Map courtesy of the Colorado River Water Conservation District.

The Colorado River basin is the major source of water for people in the driest part of the United States. More than 30 million people in 7 states depend on this river as the primary source of their water.

In this case study, you'll find out how changes in climate over the Colorado watershed are changing the amount of fresh water available in the river. You'll also see how the population of the region that uses this water has grown, resulting in increasing demands for water from this source.

Keeping Track of What You Learn

In these pages, you'll find two kinds of questions.
  • Checking In questions are intended to keep you focused on key concepts. They allow you to check if the material is making sense. These questions are often accompanied by hints or answers to let you know if you are on the right track.
  • Stop and Think questions are intended to help your teacher assess your understanding of the key concepts and skills. These questions require you to pull some concepts together or apply your knowledge in a new situation.
Your teacher will let you know which questions you should answer and turn in.