Irrigation Water Management

Irrigation Efficiency & Distribution Uniformity

PI Losses = Pre Infiltration Losses. Includes evaporation, wind drift, and runoff losses. Expressed as a % of the total water applied.

Gross Amount = depth of water applied (inches)

SMD = Soil Moisture Depletion
LR = Leaching Requirement



AE = Application Efficiency
DU= Distribution Uniformity

"With Perfect Timing" means the same as "With Good Management"
To see that this last is true, consider that with perfect timing, Dmin = SMD + LR.
Also, with perfect timing, SMD + LR = amount contributing to target = beneficial.

Thus: