Addressing the contribution of indirect potable reuse to inland freshwater salinization

Inland freshwater salinity is rising worldwide, a phenomenon called the salinization syndrome (FSS). We investigate potential conflict between managing FSS and indirect potable reuse, practice of augmenting water supplies through addition highly treated wastewater (reclaimed water) to surface waters groundwaters. From time-series data collected over 25 years, we quantify contributions three sources—a reclamation facility two rapidly urbanizing watersheds—to concentration sodium (a major ion associated with FSS) in regionally important drinking-water reservoir Mid-Atlantic United States. Sodium mass loading primarily from watershed runoff during wet weather reclaimed dry weather. Across all timescales evaluated, higher than outflow watersheds. originates chemicals added treatment, industrial commercial discharges, human excretion down-drain disposal drinking sodium-rich household products. Thus, numerous opportunities exist reduce contribution reuse pollution at this site, more generally. These efforts will require deliberative engagement diverse community stakeholders careful consideration local political, social environmental context. Freshwater an emerging threat globally. Here authors suggest variety behavioural technological interventions address growing problem.