What is drip irrigation system?

Drip Irrigation is the most efficient water and nutrient delivery system for growing crops. It delivers water and nutrients directly to the plant’s root zone, in the right amounts, at the right time, so each plant gets exactly what it needs, when it needs it, to grow optimally. It enables farmers to produce higher yields while saving on water as well as fertilizers, energy.

How does it work?
Water and nutrients are delivered across the field in pipes called ‘dripelines’ featuring small units known as ‘drippers’. Each dripper emits drops containing water and fertilizer, resulting in the uniform application of water and nutrients direct to each plant’s root zone, across an entire field.

Drip System Layout

Water Source: Irrigation water can come from a well, cistern, city council supply, or any other source that provides enough water.
Pump or Pressurized Water Source: The water source should have enough pressure to move water throughout the irrigation system and ensure good water distribution. The pressure can be maintained by installing raised tanks to utilize gravity or pumps depending on farm size. Pumps can be centrifugal, submersible, or turbine, depending on the water source and the pressure requirement. It is important to note that pumps require electricity, generators, or solar power.
Filters: Prevent particles from clogging the system. The filter should be accessible for easy cleaning. The main types of filters are disc filters, screen filters, and gravel filters.
Backwash Controllers: These devices prevent water from flowing back to the water supply system. A plumbing professional must install these to avoid contamination of the water source.
Pressure Control Valves: These maintain the water pressure in the water supply line to ensure correct operating pressure for the drip emitters at all times. This ensures that the emitters work correctly, last longer, and avoid over-watering or under-watering of crops.
Tubing: This consists of plastic pipes which carry water from the source to the crops. They can be HDPE/PVC or polyethylene, available in different diameters, lengths, and colors. Black tubing is ideal for outdoor use as it resists degradation from UV light. Tubing runs from the main line to the sub-main and then to the laterals.
Fittings and Accessories: Consists of connecting pieces between tubings and emitters/drippers. They are selected based on the size and type of tube and emitters/drippers being used. Fittings include but are not limited to elbows, couplers, tees, end caps, and valves.
Emitters or Drippers: These are the main component of a drip irrigation system. The emitters/drippers sit on the lateral lines with a spacing determined by the crop type being grown and sizes determined by crop water requirement. It is through the emitters/drippers that water is discharged to the crops. The emitters/drippers can either be pressure compensating or non-pressure compensating.
Chemical Injectors: These are sub-systems set to deliver nutrients into the irrigation system in specific quantities and time intervals. Some examples include electric dosing pump, piston motor injector, and venturi injector.
Meter: This device is installed on an irrigation system to measure the volume of water supplied to a farm.
Timer: Controls the frequency and duration of watering by being programmed to turn the irrigation system on and off at specific intervals, reducing watering during cooler weather and increasing watering frequency during hot/dry seasons.