Coefficient of Uniformity

This tool will help determine the coefficient of uniformity for irrigation.
Water Volume
Enter collection cup diameter or length and width
Diameter
 
Length
Width
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Time (min)
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Minimum of twenty four observations are needed for computing a reliable coefficient of uniformity
No valid observations found
A coefficient of uniformity above 85 (85%) is considered good for overhead impact heads and spray stakes while uniformities above 90% are considered good for drip irrigation. Coefficients of uniformity below these values suggest that your irrigation system is not performing at its best and is likely wasting water. If you want to improve your CU, it is recommended that you replace your sprinkler heads, spray stakes or drip tape and then retest your system. You can also measure the orifice size of impact sprinklers and compare those measurements to new impact sprinkler orifices. Replacing the heads may be necessary. Other things to check include making sure that the pressure at your sprinkler head is matched with what the manufacturer recommends, ensuring that your sprinkler spacing are appropriate and making sure that you are maintaining adequate flow rates through your system. A coefficient of uniformity above 85 (85%) is considered good for overhead impact heads and spray stakes while uniformities above 90% are considered good for drip irrigation. Coefficients of uniformity below these values suggest that your irrigation system is not performing at its best and is likely wasting water. If you want to improve your CU, it is recommended that you replace your sprinkler heads, spray stakes or drip tape and then retest your system. You can also measure the orifice size of impact sprinklers and compare those measurements to new impact sprinkler orifices. Replacing the heads may be necessary. Other things to check include making sure that the pressure at your sprinkler head is matched with what the manufacturer recommends, ensuring that your sprinkler spacing are appropriate and making sure that you are maintaining adequate flow rates through your system.