The autowata: Test report

Abstract

The Autowata is a trickle irrigation device developed by Methven Industries of Dunedin. The manufacturers claim that it senses soil moisture content and turns water on and off accordingly. In their words; " The unique character of the metering valve is that it responds to the individual needs of each plant. To accomplish this on-going control, each valve has a fibre wick which is partly buried in the soil and acts by capillary action on a moisture-sensitive capsule in the valve. When the soil moisture level drops, the wick acts on the sensor capsule, which shrinks, and pressure is released on a rubber diaphragm opening the valve. When the appropriate moisture condition in the soil is reached, the wick bears water to the sensor capsule, which swells, and the water flow is cut off. It is a simple, efficient system which also responds to rainfall, humidity, wind velocity and temperature. The Autowata metering valve is as functional in practice as it is simple in principle."