Locating the Site
Map 2: The Rio Grande Today
(Bureau of Reclamation)
Questions for Map 2
1. Find Elephant Butte Reservoir. How many acre-feet (“AF”) of water does it contain? “Acre-foot” is a term used by irrigation engineers to measure stored water. It is defined as the volume of water that would cover one acre of land one foot deep. Many water systems calculate that this amount of water is what a family of five uses every year. Why do you think the engineers use a measure like that, rather than something like gallons? How many gallons of water are in an acre-foot?
2. Look carefully at the section of the Project in New Mexico. First, trace the course of the river. How many reservoirs and how many diversion dams can you find? Why do you think the diversion dams are downstream of the storage reservoirs? Why do you think they have no reservoirs themselves?
3. Next, find the valleys. How many are there? How many acres does each valley contain?
4. Finally, locate the canals (shown by thin blue lines). How many can you find? See if you can identify any places where the canals cross the river. Why might that be necessary? How do you think you would go about carrying canal water over or under another watercourse?
Click for a larger version of Map 2.