Potential of wastewater reuse to alleviate water scarcity under future warming scenarios

• DOI: 10.1088/1748-9326/adb31d
• Publication Date: 2025-02-06T22:49:46Z
• Authors: Myla Kahn; Matteo Sangiorgio; Lorenzo Rosa
• Keywords: Scarcity; Wastewater Reuse

Abstract Water scarcity is a critical issue, expected to worsen with global warming. Tackling water requires strategies both decrease consumption and enhance availability. One promising solution mitigate wastewater reuse, which involves collecting, treating, repurposing used water. By employing balance model in conjunction climate outputs, we quantify the potential of reuse reduce gaps — situations where exceeds renewable availability under baseline two warming scenarios. We find that could gap by 9.1% (from 457.9 416.1 km3 per year) 8.3% 3°C scenario 524.6 480.9 year). Our analysis highlights for alleviate scarce countries metropolitan areas. India, facing world's largest gap, its 6.6% (8.2 reusing all available wastewater, compared 1.2% (1.5 reduction only currently treated wastewater. Specifically, Delhi, be reduced 29.6% full 16.6% As widens change, assure sustainable access. Drawing attention disparities access treatment, our findings can guide targeted investments treatment aiming scarcity, pollution from untreated support circular economies, ultimately ensuring sanitation.