A pilot scheme in southern Italy now irrigates olive groves with purified urban wastewater, aiming to rescue a parched agricultural sector while cutting pollution before it reaches the Adriatic Sea. The stakes pulse through Puglia, where climate shifts and a bacterial outbreak have already ravaged traditional olive farming.
Xylella fastidiosa has wiped out millions of trees across the region. Meanwhile, dwindling rainfall squeezes every remaining grower. As a result, the ECO FLOW project unites Greek and Italian researchers around a simple proposition: stop sending treated wastewater into the sea and start sending it onto roots.
The trial operates beside Gallipoli’s water treatment facility. Workers planted three rows of bacteria-resistant olive varieties, Favolosa and Lecciana, then irrigated them three different ways. One row receives conventional well water. Another gets standard treated effluent from the plant. The third receives wastewater run through an additional patented purification step.
Rocco Protopapa from ARIF, Puglia’s regional irrigation agency, described the core comparison. Researchers measure fruit yield and quality across all three irrigation methods. “We want to see how much fruit they produce and how they produce it,” he said. “And that way we avoid wasting water that would otherwise end up in the sea.”
The extra purification technology emerged from a previous European initiative called RE-WATER. Fabrizio Dell’Anna of Acquedotto Pugliese explained how hydrogen peroxide combines with ultraviolet light inside a thermally insulated reactor. That reaction spawns highly reactive molecules capable of breaking down pollutants. Because no commercial equipment matched the specifications, the team engineered the system themselves, discovering that circulating water boosted the number of reactive molecules available to attack contaminants.
ECO FLOW operates with a budget exceeding €1.5 million. European cohesion policy covers 75 percent, while Greek and Italian national funds supply the remainder. Greek partners focused on physical membrane filtration, while Italian researchers pursued the chemical approach. Both methods work in tandem, according to project experts.
Danilo Spasiano from the Polytechnic University of Bari said monitoring has recently begun. His laboratory tracks water chemistry, plant growth, soil characteristics, and accumulation of trace substances in the ground.
Antonio Astuto, whose farm produces over sixty tonnes of olives annually, noticed a striking difference. Four-year-old trees irrigated with purified wastewater began fruiting unexpectedly early. “We were very happy to see that the plants grew quicker, probably thanks to the type of water used,” he said. The two-year pilot now tests whether that early promise holds through full harvest cycles.
