Agricultural Micro Irrigation

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:

• Made of uPVC or PE
• Connected using fittings such as Xpando Take-Offs

8. Lateral Pipework

Delivers water along the crop rows. Usually made of:

• Low Density Polyethylene (LDPE)

9. Emitters

Apply water directly to the root zone. Options include:

• Drippers
• Micro sprays
• Mini sprinklers

10. Flushing Points

Properly designed systems include flushing points to remove sediment and maintain water quality throughout the network.