From Area to get the Flow of Irrigation

2018-09-20 16:10
Area to Flow

The key of design is the calculation of irrigation water consumption.
For small-scale irrigation projects, there is a amount of water often encountered, that is, "water for land or land for water" problem.
Assuming the total amount of water coming in is Q (cubic meters per hour), your design idea is to use up this flow to irrigate, then how many areas of land it can be irrigated.

The expression in a literal formula is:
Irrigation area A = water supply W / water use ETc = (water supply Q * working time t) / (design water consumption ETc / Wn irrigation water coefficient) = water volume / irrigation depth.
Using written formulas is to make it clear that the calculation of the formula is a simple middle school mathematical, that is, area = volume / depth (height).
In general, there is already a need for irrigation area, the need to calculate the size of water supply, or pump flow, head.
If T day cycles are used to design, you have to follow the steps. Here is a simple method to calculate the water consumption of crops only for one day.
Irrigation water m1= crop water consumption ETc.
The amount of water needed is W=, the amount of irrigation water is m1 X, mutiply the irrigation area is A.
Water source (pump) flow Q= required water quantity W/ system daily irrigation time t.
Of course, the efficiency of water quantity should be taken into account. Irrigation flow Q = water quantity m1*A / irrigation efficiency Wn / irrigation work time t of the system for a day.

Q=m1*A/ Wn /t/1000.

The 1000 is the unit conversion (from millimeter to meter) coefficient.
Knowing the area of the irrigation project, you can calculate the amount of water that the project should need. If the flow is insufficient, you can find a way to replenish the water from other channels. Such as drilling wells, increasing reservoirs, excavating ponds and so on.
For example, if your irrigation project area is 120 mu, working time can reach 12 hours, crop water consumption is 4 mm / day, using sprinkler irrigation, irrigation efficiency is 85%, then you need irrigation flow is:

Q=4*120*667/0.85/12/1000=31.39 cubic meter / hour.

Known irrigation area A, calculation of irrigation flow Q.


  1. If the input unit is inconsistent with the formula set unit, then convert the unit.
  2. Click  "Convert " button
  3. Enter numeric values in the pop-up menu.
    The result of the transformation will be displayed in the corresponding output bar.
  4. There is no need to convert the units in accordance with the set units, and directly enter the value of standard units. The value of the program must be replaced by your own value.

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Area A - fromto sq m  

Irrigation Area(m^2):                        

Crop water consumption m1 - fromto m

Crop water consumption(m):

Application efficiency

Application efficiency Wn(%):

Allowed irrigation time per day

Irrigation time t(h):

Irrigation flow(cu m/h)

Result Q (cu m/h):