Gross Irrigation Requirement (GIR) is the total amount of water
that must be applied at the field inlet to satisfy the
net irrigation requirement, considering
losses due to application inefficiency.
Standard Agronomy Formula
GIR = NIR / Ei
Where:
• NIR = Net irrigation requirement (mm)
• Ei = Irrigation efficiency (decimal form)
Enter Required Data
Important Notes:
• Efficiency must be converted into decimal
• Lower efficiency → higher GIR
• Used in canal, sprinkler & drip irrigation planning
