Core Components of a Typical Agricultural Micro Irrigation System
1. Water Supply
The water source can be:
Open sources such as rivers, channels, dams, or tanks
Groundwater sources such as bores or wells
2. Pump
The pump supplies energy to operate the system. When selecting a pump, consider:
Operating pressure of micro emitters
Friction losses in the pipes
Elevation changes
Losses from valves, fittings, and filters
Allowances for system inefficiencies and ageing
A well-chosen pump ensures optimal efficiency and long-term performance.
3. Fertigation / Chemigation
Fertigation allows soluble fertilisers to be applied through the irrigation system, with efficiencies of up to 90%.
Chemigation involves injecting cleaning agents like chlorine or acid to flush contaminants from the system.
4. Filtration
Filtration is essential for removing debris from the water supply:
Media filters are effective for open water sources with organic matter
Disc or screen filters are common for groundwater with inorganic particles
Regular cleaning and maintenance (manual or automated) are essential for peak performance. Consult a certified irrigation designer to select the right filtration system.
5. Mainline
Transfers water from the source to the zone control valves. Usually made from:
uPVC or PE (Polyethylene) pipes
Designed to maintain flow velocities below 1.5 m/s
Changes in direction should be thrust blocked (anchored with concrete)
6. Zone Control Valves
These valves control the flow to each irrigation zone and may be:
Manual or automated (solenoid valves)
Equipped with pressure regulators for consistent downstream pressure
Paired with air/vacuum relief valves
7. Submain
Connects the mainline to lateral pipes. Typically: