A major advance in drip irrigation
What is measured irrigation?
Measured irrigation is an irrigation scheduling technique.
For conventional drip irrigation systems, the volume of water delivered by a dripper during the irrigation event depends upon the flow rate. But for measured irrigation the volume of water delivered by a dripper during the irrigation event is independent of the flow rate.
An irrigation system that is independent of the flow rate is a potential threat to multinational irrigation companies that have billions of dollars invested in pressurised irrigation technology. It is not surprising therefore that no irrigation company worldwide has so far shown any interest in measured irrigation. If you are interested in measured irrigation you are unlikely to receive any encouragement or support from the irrigation industry.
Measured irrigation can be completely automatic with the irrigation frequency and water usage directly proportional to the net evaporation rate (evaporation minus rainfall).
Measured irrigation is usually gravity feed and can be automated without access to mains water or mains power, and so there are no ongoing costs for mains water or electricity.
Measured irrigation is well suited to smallholders in poorer countries. At almost no cost, a smallholder can upgrade gravity feed drip irrigation to measured irrigation using a bucket and a steel pipe.
You can upgrade any irrigation system (drip or sprinkler, pressurised or gravity feed, pressure compensating drippers or non pressure compensating drippers)) to a fully automated measured irrigation system using the Unpowered Measured Irrigation Controller (no electricity is needed) or the Universal Measured Irrigation Controller
You can upgrade a gravity feed drip irrigation system with a farm pond to a fully automated measured irrigation using the DIY Solar Drip Irrigation Kit. Water is pumped automatically from the farm pond to a header tank.
Measured irrigation is simple and low tech and hence there are fewer things to go wrong – ideal for smallholders with limited access to technical and maintenance support.
Definition of measured irrigation
Measured irrigation is an irrigation scheduling method that satisfies the following two conditions:
Variations in the water usage throughout the year are controlled by the prevailing net evaporation rate
(evaporation minus rainfall).
The volume of water discharged by each emitter during an irrigation event is controlled directly without the need to control the flow rate or the duration of the irrigation event.
In September 2019, the Unpowered Measured Irrigation Controller was accepted by the Expert Panel for the
Smart Approved WaterMark.
News Update, February 2020
Just released, key features include:
Use with a tap timer, a programmable irrigation controller, or use as a stand-alone irrigation controller
Smart irrigation controller – controlled by the weather
Use for both gravity feed and pressurised irrigation
Use for any size irrigation system, large or small
Use for sprinkler or drip irrigation
Use for weeper or soaker hose irrigation
Use for pressure compensating drippers or non pressure compensating drippers.
Water usage is directly proportional to the net evaporation rate – a unique feature of measured irrigation
Water usage is independent of the water supply pressure
– a unique feature of measured irrigation
By using a zero pressure solenoid valve and the Universal Measured Irrigation Controller, you can irrigate directly from your rainwater tank without a pump. The water usage for measured irrigation is controlled by the prevailing weather conditions and is independent of the water level in the tank. The Universal Measured Irrigation Controller is a game-changer for automated irrigation from a rainwater tank (or header tank) without using a pump or timer. Low pressure means that hose clamps are not needed.
Unpowered MI Training Manual for Smallholders has
detailed instructions for upgrading any drip irrigation system to unpowered measured irrigation. The irrigation system may be controlled manually or you may wish to use the Unpowered Measured Irrigation Controller or the DIY Smart Irrigation Controller.
DIY Solar MI Training Manual for Smallholders has detailed instructions for upgrading gravity feed drip irrigation to
solar-powered measured irrigation. Water is pumped automatically from a farm pond to a header tank and all your plants are watered automatically from the header tank.
Universal Measured Irrigation Controller User Manual is the User Manual for this smart irrigation controller that can be used for any irrigation application.
Measured Irrigation from Scratch Manual provides detailed instructions for installing an irrigation system from scratch using measured irrigation. The theoretical foundation for measured irrigation is included.
Evapotranspiration and Measured Irrigation: Report for Smart Approved Watermark demonstrates a 90% correlation between measured irrigation discharge volumes and the prevailing evapotranspiration minus rainfall.
Research Report: Improvement in crop yield per litre using Measured Irrigation reports on a pilot trial in Adelaide demonstrating improvements in crop yield per litre of more than 100%.