Barcelona bets on greywater: sustainable solution or missed opportunity?

Barcelona has taken a significant step in tackling the water crisis by introducing new regulations promoting greywater reuse in buildings. But is this truly a transformative change, or does it fall short of addressing the urgent needs?

Clear objectives behind the new regulation

At the end of June, Barcelona City Council approved the Greywater Utilisation Ordinance aiming to advance more efficient water management and meet the commitments of the Climate Plan. This regulation requires new constructions — and those undergoing major renovations — to integrate systems for recovering and treating greywater.

This change is significant: it is estimated to affect 70% of new homes, 100% of hotels, and nearly 90% of sports facilities, with a projected annual saving of 136,000 m³ of potable water. Additionally, the measure complements the expansion of the groundwater network, another alternative non-potable water source.