Water-efficient irrigation puts water into the root zone, in the amount the crop needs, at a time when little is lost to evaporation or runoff. Surface flooding and overhead sprinklers waste a large share of the water, while drip, buried clay pots and wicking beds waste much less, and the carrier guide’s figures are 40-70% lost against 5-15%. Both are unsourced, so measure what your own system delivers to the root zone before planning around them.
Water-efficient irrigation is the use of methods and schedules that deliver the water crops need with the least loss to evaporation, runoff and deep drainage.
Efficiency Is A Fraction, And It Depends On Method, Soil And Timing
Irrigation efficiency is the fraction of the water you apply that the crop actually uses. The rest is lost by evaporation from wet leaves and soil, runoff, drift in wind and drainage below the roots. The carrier guide (Drought Resilience & Water-Efficient Agriculture) says that surface flooding and overhead sprinklers waste 40-70% of water to evaporation and runoff, and that targeted methods reduce waste to 5-15%. The carrier gives no source, and the true figures depend on soil, slope, wind, temperature and how carefully the system is run.
What Counts As Efficient
- Put the water where roots are. Drip lines, buried pots and wicks deliver to the root zone and wet little else (Drip Irrigation, Clay Pot Irrigation, Wick Systems).
- Apply less often, more deeply so roots go deeper.
- Water when evaporation is low, early morning or evening, and not in strong wind.
- Keep leaves dry to reduce disease.
- Cover the soil with mulch to cut evaporation (Mulching & Soil Moisture).
Method: Measure Before You Trust
Step 1: Catch-can test. Place several identical containers across the watered area, run the system for a set time and measure the depth collected in each. The spread shows how even the delivery is.
Step 2: Dig after watering. An hour after irrigation (and a day after), dig and look at how deep the wet soil reaches. If it is wet to the root depth and no deeper, the amount is about right.
Step 3: Compare with the need. See Scheduling: When and How Much.
Step 4: Choose the method by water supply, labour and parts available: Drip Irrigation from Salvage Materials or Olla (Clay Pot) Irrigation.
Common Mistakes
- Watering by habit — the crop’s need changes with weather.
- Watering a little every day — shallow roots.
- Watering at midday in wind — much is lost before it reaches the soil.
- Trusting percentages — measure.
What’s Next
- Learn next: Drip Irrigation from Salvage Materials — building a system
- Combine with: Mulching & Soil Moisture — the surface cover that stretches every litre