Core Case Study: The Colorado River Story. 1400 miles through 7 states14 dams and reservoirsElectricity for 30 million peopleWater for 15% of U.S. crops and livestockWater for desert citiesVery little water reaches the Gulf of California. Fig. 11-1, p. 238. Fig. 11-2, p. 238. 11-1 Will We Have Enough Usable Water?.