Agriculture, Soil, Fertilizer & Farm Operations worked example

Irrigation Water Requirement at 98% irrigation system application efficiency: a worked example

Push irrigation system application efficiency up to 98% and the picture changes. This example computes every intermediate figure at that operating point. Use it to plan irrigation sets, pump volume, water allocation, or seasonal irrigation scheduling.

The inputs for this scenario

  • Irrigated field area: 80 acres (unchanged)
  • Net irrigation depth to apply: 0.75 inches (unchanged)
  • Irrigation system application efficiency: 98 % (raised for this scenario; the documented default is 85)

Working through the calculation

  • Applying the documented formula (Water required = irrigated acres x target depth / application efficiency) to the inputs above produces each figure below.
  • At this operating point the engine returns 61.22 acre-inches for irrigation water required, the number this scenario is built around.
  • At this operating point the engine returns 60 acre-inches for net crop water target.
  • At this operating point the engine returns 1.22 acre-inches for irrigation loss allowance.
  • At this operating point the engine returns 98 % for application efficiency.

How this compares with the baseline

  • Against the tool's baseline example, where irrigation system application efficiency sits at 85% and the headline result is 70.59 acre-inches, this scenario comes in 13.27% below the baseline at 61.22 acre-inches.
  • It computes the gross acre-inches to pump, plus the net crop water target and the loss allowance, from acres, depth, and efficiency. The value of this scenario is the size of the gap it exposes: that gap, priced out over a year, is the budget you can justify spending to close it.

Results at a glance

  • Irrigation water required: 61.22 acre-inches (headline result)
  • Net crop water target: 60 acre-inches
  • Irrigation loss allowance: 1.22 acre-inches
  • Application efficiency: 98 %

Run it with your numbers

  • Every input above is editable in the live Irrigation Water Requirement calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.