Irrigation scheduling is the process used by irrigation system managers to determine the correct frequency and duration of watering.
Irrigation Scheduling Quick Facts:
- Irrigation scheduling is the decision of when and how much water to apply to a field.
- Its purpose is to maximize irrigation efficiencies by applying the exact amount of water needed to replenish the soil moisture to the desired level.
- Irrigation scheduling saves water and energy.
- All irrigation scheduling procedures consist of monitoring indicators that determine the need for irrigation.
The importance of irrigation scheduling is that it enables the irrigator to apply the exact amount of water to achieve the goal. This increases irrigation efficiency. A critical element is accurate measurement of the volume of water applied or the depth of application. A farmer cannot manage water to maximum efficiency without knowing how much was applied.
Uniform water distribution across the field is important to achieve the maximum benefits from irrigation scheduling/management. Accurate water application prevents over or under irrigation. Over irrigation wastes water, energy and labor; leaches expensive nutrients below the root zone, out of reach of plants; and reduces soil aeration, and thus crop yields. Under irrigation stresses the plant and causes yield reduction.
Irrigation scheduling offers several advantages:
- It enables the farmer to schedule water rotation among the various fields to minimize crop water stress and maximize yields.
- It reduces the farmer’s cost of water and labor through fewer irrigations, thereby making maximum use of soil moisture storage.
- It lowers fertilizer costs by holding surface runoff and deep percolation (leaching) to a minimum.
- It increases net returns by increasing crop yields and crop quality.
- It minimizes water-logging problems by reducing the drainage requirements.
- It assists in controlling root zone salinity problems through controlled leaching.
- It results in additional returns by using the “saved” water to irrigate non-cash Crops that otherwise would not be irrigated during water-short periods.