Living Land

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Rethinking the sustainability of Israel’s

irrigation practices in the drylands

Professor Alon Tal, Blaustein Institutes for Desert Research, Ben Gurion University

srael’s strategy to combat desertification includes

a determined effort to expand agricultural produc-

tion in the drylands. Two central components of this

effort are the wide utilization of drip irrigation technol-

ogies and a complete commitment to ‘marginal’ water

sources, in particular recycled wastewater. Initial results

have been hailed as extraordinarily impressive, with

dramatic growth in yields with practically no increased

freshwater allocations. Yet, a growing scientific consen-

sus suggests that Israel’s approach to irrigation may be

fundamentally unsustainable.

Israel began developing drip irrigation some 50 years ago. The

technology was soon hailed as a breakthrough in agricultural

efficiency. In the country’s early years, furrow and gravity

based flooding systems had been normative. By contrast, drip

systems delivered tiny amounts of water and fertilizer directly

to the root zone of plants and trees in a steady flow. The

new technology immediately produced significantly “more

crop for the drop” and offered farmers myriad operational

and environmental benefits: reduced diseases, weeds, labour

costs and nonpoint source pollution discharges. At the same

time, nutrients and chemicals were more efficiently delivered

directly to the root zones of plants.

The technical capabilities of drip irrigation quickly

improved. Drip systems became more robust and durable,

with emitters able to process lower quality waters without

clogging. Subsurface irrigation systems were eventually devel-

oped to solve environmental problems, especially for systems

utilizing treated effluents. Keeping wastewater underground

adds an additional level of safety, preventing the likelihood

of contact with produce or exposure among workers. It also

allows for drippers to release water precisely where it is

needed, in the root zones, 20 cm underground. Today, some

Israeli drip irrigation technology applied in Africa

Image: Naty Barak

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