Achieving water security requires reconciling multiple objectives while prioritizing scarce resources for the provision of safe drinking water supplies. We examine decision-making to invest in drinking water infrastructure in coastal Bangladesh where increasing saline intrusion in aquifers intersects with high levels of poverty for the 20 million people living in the coastal region. Multi-objective optimization is used to explore the trade-offs between two public policy goals: (a) maximizing overall access to improved water supplies (the greater good) and (b) maximizing access for the population with the lowest welfare (the greater need). To elucidate this trade-off, we make use of groundwater salinity measurements, an extensive household survey and an audit of drinking water infrastructure in 1 out of Bangladesh’s 139 polders, which is home to nearly 60,000 people. We quantify the costs of a variety of drinking water supply options including deep tube wells, desalination plants, and piped systems. The recommended solutions are sequences of investments in water supply assets that are optimized to specified locations within the polder. The method is potentially scalable and transferrable to inform investments to achieve the Sustainable Development Goal (Target 6.1) of universal access to safe and affordable drinking water.

中文翻译：

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优化农村饮用水供应基础设施以应对孟加拉国沿海地下水质量和家庭福利的空间变化

实现水安全需要协调多个目标，同时优先考虑稀缺资源以提供安全的饮用水供应。我们研究了在孟加拉国沿海地区投资饮用水基础设施的决策，其中含水层中盐分入侵的增加与生活在沿海地区的 2000 万人的高度贫困相交。多目标优化用于探索两个公共政策目标之间的权衡：(a) 最大限度地提高总体获得改善的供水（更大的利益）和 (b) 最大限度地提高福利最低的人口（更大的需求）的获得）。为了阐明这种权衡，我们利用地下水盐度测量、广泛的家庭调查和对孟加拉国 139 个圩田中的 1 个圩田的饮用水基础设施进行审计，这是近60,000人的家园。我们量化了各种饮用水供应方案的成本，包括深管井、海水淡化厂和管道系统。推荐的解决方案是对供水资产的投资序列，这些资产针对圩田内的指定位置进行了优化。该方法具有潜在的可扩展性和可转移性，可为投资提供信息，以实现普遍获得安全和负担得起的饮用水的可持续发展目标（目标 6.1）。