Measure field performance for drip, sprinkler, or hose. Spot runoff, evaporation, and deep percolation losses. Get clear targets and actions for better watering results.
| Scenario | Applied water | Effective water | DU | Efficiency result |
|---|---|---|---|---|
| Drip on raised beds | 1200 L | 900 L | 90% | Overall ≈ 67.50% |
| Sprinklers on lawn | 18 m³ | 12 m³ | 75% | Overall ≈ 50.00% |
| Manual hose watering | 500 US gal | 260 US gal | 60% | Overall ≈ 31.20% |
Application efficiency estimates how much applied water becomes beneficial.
Application Efficiency (%) = (Effective Water / Applied Water) × 100
Overall irrigation efficiency also accounts for distribution uniformity.
Overall Efficiency (%) = Application Efficiency × (DU / 100)
If you do not provide effective water, it is estimated as:
Effective = Applied × (1 − Total Loss%/100).
Irrigation efficiency compares beneficial water stored in the root zone to total water applied. This calculator reports application efficiency and then adjusts it by distribution uniformity to reflect uneven wetting across beds, lawn zones, or containers. Tracking both values helps separate scheduling issues from hardware issues. Many gardens operate between 30% and 80%, depending on method and maintenance.
Start with applied water from a meter, tank volume, or flow rate multiplied by runtime. Estimate effective water using soil moisture change, a simple water balance, or by entering losses when direct measurement is not feasible. Use the depth-over-area option when you have measured millimeters from catch cans or rainfall gauges. Record date, weather, and irrigation duration to build a comparable log.
Distribution uniformity represents how evenly water is delivered. A high DU means most plants receive similar depths, reducing the need to overwater to satisfy dry spots. For sprinklers, catch-can tests across the pattern support DU estimates. For drip, compare emitter flow at the head and far end, and verify pressure regulation. As a guide, DU above 85% is strong, 70–85% is workable, and below 70% needs attention.
Common loss pathways include evaporation from wetted surfaces, runoff from slopes or compacted soil, and deep percolation beyond roots. Reduce evaporation with morning irrigation, mulch, and lower spray height. Reduce runoff by shortening cycles, improving infiltration, and leveling basins. Reduce deep percolation by matching runtime to soil intake and rooting depth. Sandy soils accept faster but drain quickly, while clay soils need shorter cycles and longer soak periods.
Use results to set practical targets. Drip systems often achieve higher uniformity and lower runoff, while sprinklers may require nozzle selection and pressure tuning. Recheck performance after filter cleaning, emitter replacement, and seasonal adjustments. Saving even 10% of applied water can lower pumping time, reduce disease pressure, and improve nutrient retention. Track weekly water savings.
It combines how much applied water becomes beneficial with how evenly water is distributed. High overall efficiency indicates both good scheduling and uniform delivery across the irrigated area.
No. If an estimate exceeds applied water, measurement or unit inputs are likely inconsistent. The calculator caps effective water to applied water to keep results realistic.
Use reasonable loss percentages for runoff, evaporation, and deep percolation based on soil, slope, and method. Start with the system defaults, then refine after observing puddling, drift, and drainage.
Clean filters, check pressure, repair leaks, and replace clogged emitters or worn nozzles. For sprinklers, adjust spacing and nozzle type, and verify head-to-head coverage using catch cans.
Use it when you measure water depth in millimeters across a known area, such as catch-can tests or measured infiltration. It is also useful for comparing irrigation to rainfall equivalents.
Targets vary by method. Drip and micro systems often reach higher values than sprinklers or hoses when maintained. Use your first measurement as a baseline, then aim for steady improvement rather than a single “perfect” number.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.