School of Geography and the Environment, University of Oxford, South Parks Rd, Oxford, UK.
Department of Civil Engineering and Cabot Institute of the Environment, University of Bristol, University Walk, Bristol BS8 1TR, UK.
Sci Total Environ. 2022 Mar 20;813:151876. doi: 10.1016/j.scitotenv.2021.151876. Epub 2021 Nov 23.
Climate resilient water supplies are those that provide access to drinking water that is sustained through seasons and through extreme events, and where good water quality is also sustained. While surface and groundwater quality are widely understood to vary with rainfall, there is a gap in the evidence on the impact of weather and extremes in rainfall and temperature on drinking water quality, and the role of changes in water system management. A three-country (Bangladesh, Nepal and Tanzania) observational field study tracked 2353 households clustered around 685 water sources across seven different geographies over 14 months. Water quality (E. coli) data was modelled using GEE to account for clustering effects and repeated measures at households. All types of infrastructure were vulnerable to changes in weather, with differences varying between geographies; protected boreholes provided the greatest protection at the point of collection (PoC). Water quality at the point of use (PoU) was vulnerable to changes in weather, through changes in PoC water quality as well as changes in management behaviours, such as safe storage, treatment and cleaning. This is the first study to demonstrate the impact of rainfall and temperature extremes on water quality at the PoC, and the role that weather has on PoU water quality via management behaviours. Climate resilience for water supplies needs to consider the infrastructure as well as the management decisions that are taking place at a community and household level.
具有气候适应能力的供水系统是指能够在季节变化和极端事件中持续提供饮用水的系统，并且能够维持良好的水质。虽然地表水和地下水的质量普遍被认为会随降雨量而变化，但对于天气和极端降雨及温度对饮用水质量的影响，以及供水系统管理变化的作用，仍存在证据空白。一项涉及孟加拉国、尼泊尔和坦桑尼亚三国的观测性实地研究，在 14 个月的时间里，跟踪了 2353 户家庭，这些家庭分布在 7 个不同地理位置的 685 个水源周围。使用 GEE 对水质（大肠杆菌）数据进行建模，以解释家庭层面的聚类效应和重复测量。所有类型的基础设施都容易受到天气变化的影响，不同地理位置之间存在差异；在收集点（PoC），受保护的钻孔提供了最大的保护。由于 PoC 水质的变化以及安全储存、处理和清洁等管理行为的变化，用水点（PoU）的水质容易受到天气变化的影响。这是第一项研究，证明了降雨和温度极端对 PoC 水质的影响，以及天气通过管理行为对 PoU 水质的作用。供水系统的气候适应能力需要考虑基础设施以及社区和家庭层面的管理决策。
