There is increasing awareness of household self-supply and the role it can play in securing water for domestic needs in low- and middle-income countries (LMICs), but its scale across the Asia-Pacific has not previously been quantified. This study analysed 77 datasets from 26 countries to estimate the prevalence of self-supplied drinking water, and its associated trends in LMICs in South Asia, Southeast Asia and the Pacific. When factoring in temporal trends, results suggest that >760 million people—or 31% of the population—relied on self-supply for their drinking water in these regions in 2018, with the number of users increasing by >9 million each year. Reliance on self-supply for drinking water is greater in rural areas than in urban areas (37% of rural population vs 20% of urban population), though results vary considerably between countries. Groundwater sources constitute the most common form of self-supply in South Asia and Southeast Asia, while rainwater collection is dominant in the Pacific. The results confirm the significance of self-supply in the Asia-Pacific and suggest that households are a major but often overlooked source of financing within the water sector. The findings raise important questions about how policy and practice should respond to this widespread phenomenon.

人们越来越意识到家庭自给自足及其在中低收入国家 (LMIC) 的家庭用水保障方面所发挥的作用，但其在亚太地区的规模此前并未被量化。本研究分析了来自 26 个国家/地区的 77 个数据集，以估计南亚、东南亚和太平洋地区中低收入国家的自给饮用水流行率及其相关趋势。考虑到时间趋势，结果表明，2018 年这些地区有超过 7.6 亿人（占总人口的 31%）的饮用水依靠自给自给，用户数量每年增加超过 900 万。农村地区对饮用水的依赖程度高于城市地区（农村人口的 37% 对城市人口的 20%），尽管各国之间的结果差异很大。地下水源是南亚和东南亚最常见的自给形式，而雨水收集在太平洋地区占主导地位。结果证实了自给自足在亚太地区的重要性，并表明家庭是水务部门一个主要但经常被忽视的融资来源。研究结果提出了关于政策和实践应如何应对这一普遍现象的重要问题。