Life Cycle Assessment of Reclaimed Water Irrigation in Organic Vineyards: Environmental Impacts and Water Stress Implications in La Rioja, Spain

Agriculture puts significant pressure on freshwater sources, which motivates the use of reclaimed water for irrigation as a promising alternative to reduce freshwater demand while also providing nutrients. This study applies Life Cycle Assessment to determine the environmental impacts of irrigating a DOCa La Rioja vineyard with reclaimed water in the cultivation of organic grapes (scenario A) and compares it with an irrigation practice that uses canal water combined with organic extra-fertilisation (scenario B), accounting for differences in wastewater treatment processes. Results show that scenario A reduces impacts in categories such as global warming (16.2%) and freshwater eutrophication (25.6%) compared with scenario B, primarily due to the lower emissions associated with reclaimed water treatment. Additionally, a water balance was performed for the plot, which indicated that current inputs currently exceed losses in the region, so water stress is not observed; however, this situation may change in the near future due to population growth and climate change. These findings underscore the need to enhance the efficiency of the reclaimed water production, primarily by optimising its energy requirements, to support sustainable water use in agricultural systems.