50 Ways - 49. Take Precautions When Irrigating

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50 Ways Farmers Can Protect Their Groundwater

Nitrogen

1. Set realistic yield goals
2. Test the soil
3. Credit other nitrogen sources
4. Apply nitrogen in the spring
5. Use nitrification inhibitors when effective

Scouting

6. Scout fields

Insecticides

7. Know the economic thresholds for insects
8. Consider insect-resistant crop varieties
9. Spot-treat insect infestations when possible
10. Know how tillage affects insects
11. Know how crop rotation affects insects
12. Adjust planting & harvesting dates to control insects
13. Conserve beneficial insects
14. Consider using biological insecticides

Herbicides

15. Know the economic thresholds for weeds
16. Fine-tune your weed program to reduce rates
17. Manage crops to compete aggressively with weeds
18. Don't increase herbicide rates with conservation tillage
19. Band herbicides and cultivate
20. Control weeds with cover crops

Pesticide Selection

21. Determine the organic-matter of your soil
22. Determine your soil's potential for leaching
23. Determine your pesticide's potential for leaching
24. Determine the soil-pesticide interaction rating
25. Consider other critical pesticide qualities

Pesticide application

26. Select the proper nozzle tips
27. Calibrate your sprayer
28. Consider direct injection
29. SPrevent backsiphoning

Pesticide disposal and storage

30. Rinse chemical containers thoroughly
31. Dispose of rinsed containers safely
32. Dispose of excess chemicals safely
33. Store agrichemicals safely
34. Prevent and clean up chemical spills
35. Construct a rinse pad

Site conditions, wells, and septic systems

36. Know your well site conditions
37. Locate your well away from contamination sources
38. Make sure your well is constructed properly
39. Seal abandoned wells
40. Make sure your septic system operates correctly

Water testing & treatment

41. Test your water routinely
42. Test your water for coliform bacteria & nitrate
43. Test you water for pesticides
44. Know the signs of contaminants in drinking water
45. Select effective water-treatment methods

46. Store livestock waste properly
47. Have old, underground fuel storage tanks removed
48. Dispose of other hazardous waste safely
49. Take precautions when irrigating
50. Take precautions when chemigating

49. Take Precautions When Irrigating
	There are several types of irrigation, and each has its own special benefits and problems when it comes to groundwater. With furrow irrigation, water is ponded between crop rows created during planting and cultivation. With flood irrigation, water is pumped or allowed to flow into a ridged or diked area of the field. The basic risk with these systems is overapplication of water. Overapplication increases the chances that surface-applied or soil-incorporated pesticides will leach to the groundwater supply—particularly if the soil is highly permeable.
	Sprinkler irrigation sprays water into the air through perforated pipes or nozzles. For row crops, this system poses the least risk to groundwater because water can be applied more precisely than with flood or furrow irrigation. Also, a sprinkler irrigation system makes it easier to put down nitrogen in split applications. With split applications, less N is lost, reducing the risk to groundwater.
	Trickle or drip irrigation applies water very slowly on or beneath the soil surface near the plant. Because this method doesn't use much water, it is probably the safest in terms of leaching. However, trickle irrigation is not practical for row crops. There is also the potential of overapplication, as with all other systems. Overapplication could mean increased leaching.
	If possible, delay irrigation for at least one day after applying a chemical. This will give the chemical a chance to degrade and attach to soil particles. If the chemical is postemergent, delaying irrigation will also give the chemical a chance to be taken up by the plant.