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

世界范围内陆淡水盐度正在上升，这种现象称为淡水盐化综合症（FSS）。我们调查了FSS管理与间接饮用水再利用之间的潜在冲突，间接做法是通过在地表水和地下水中添加经过高度处理的废水（再生水）来增加水供应。根据过去25年收集的时间序列数据，我们量化了三个盐度源（一个水回收设施和两个快速城市化集水区）对区域重要饮用水中钠（与FSS相关的主要离子）浓度不断上升的贡献。美国中大西洋的水库。钠质量负荷主要来自潮湿天气期间的分水岭径流和干旱天气期间的再生水。在所有评估的时间范围内，再生水中的钠浓度高于两个分水岭的流出量。再生水中的钠源自废水处理，工业和商业排放，人类排泄以及饮用水和富含钠的家用产品的下水道处理过程中添加的化学物质。因此，存在许多机会来减少该地点的间接饮用水再利用对钠污染以及FSS的贡献。这些努力将需要与分水岭利益相关者的多元化社区进行协商参与，并仔细考虑当地的政治，社会和环境环境。人体排泄和饮用水和富含钠的家用产品的下水道处理。因此，存在许多机会来减少该地点的间接饮用水再利用对钠污染以及FSS的贡献。这些努力将需要与分水岭利益相关者的多元化社区进行协商参与，并仔细考虑当地的政治，社会和环境环境。人体排泄和饮用水和富含钠的家用产品的下水道处理。因此，存在许多机会来减少该地点的间接饮用水再利用对钠污染以及FSS的贡献。这些努力将需要与分水岭利益相关者的多元化社区进行协商参与，并仔细考虑当地的政治，社会和环境环境。