NEW IRRIGATION SYSTEMS: making do with less

With dwindling water supplies and a greater emphasis on efficient use of resources, irrigation technology is evolving to make do with less. While the initial capital costs of the latest equipment and software may be high, its increased efficiency, higher yield and reduced water usage cannot be beaten. Lindi Botha spoke to experts about the latest advances in irrigation.

- Lindi Botha

Irrigation supports 25% to 30% of national agricultural production in South Africa. Although irrigated agriculture uses 62% of the available water resources in South Africa, the importance of this sector for the economy and food security is undisputed.

Reducing hectares under irrigation is therefore not the answer to water shortages. What is needed is more efficient use of the water that is available.

To this end, innovations in the field have included low-flow drip irrigation, draglines and micro sprinklers, all of which have succeeded at growing crops optimally while using less water.

As the new decade dawns, even greater improvements are coming into play. Felix Reinders, programme manager at the Agricultural Research Council’s Department of Agricultural Engineering, notes that new and emerging technologies or solutions in irrigation can be grouped into three main categories: augmenting and improving water supply; improving water productivity; and managing irrigation systems more efficiently.

•  Augmenting and  improving water supply.

This includes irrigation systems that make use of solar and wind power; software that controls water productivity, from dam water release to root zone application; and integrated water administration systems that deliver water on demand through canal networks and rivers.

•  Improving water productivity.

Innovations here include pivot drip systems that combine the efficiency of surface drip irrigation with the flexibility and cost-effectiveness of mechanised irrigation systems, and integrated sensors to monitor soil and plants. Through wireless communication, the sensors help algorithms to better control and manage the irrigation systems.