APES Name: ______________________

Irrigation Methods

Introduction: An acre of corn will use about 600,000 gallons of water from planting to harvesting. The average cost of water in the United States is only about $1.50 per 1000 gallons. In class we have learned about 5 different irrigation methods. Each irrigation method has benefits and drawbacks. Those that are easy to use tend to be not very efficient and vice versa. Using your notes and textbook, answer the questions below. When doing the math you can assume the lower value for efficiency if there is a range of values.

1. Describe flood irrigation.

2. How efficient is flood irrigation?

3. Considering your answer to number 2, and the information about corn in the introduction, how much water would have to be applied to an acre of corn using flood irrigation to make sure that the corn received the amount of water that it needs to use?

4. How much would this amount of water cost a farmer?

5. What is LEPA?

6. How efficient is LEPA?

7. How much water would need to be applied to a field of corn using LEPA?

8. How much money would this cost a farmer?

9. How much water could be saved per acre of corn if a farmer switches from flood irrigation to LEPA?

10. How much money could this save the farmer on water costs?

11. Explain why there is little incentive for farmers to make the switch to more efficient irrigation methods.

12. What are government subsidies, and how might they contribute to the problem of water use?

13. What irrigation method is pictured?

14. What is the efficiency of this irrigation method?

15. How is water wasted in spray irrigation?

16. Describe drip irrigation and its efficiency.

17. List the irrigation methods in order from least to most efficient

18. Besides new irrigation methods, what are some other ideas about how to save water?

19. Explain how raising the price of water can help to conserve it. Use the examples at the beginning of this worksheet in your answer.