A hidden crisis? Strengthening the evidence base on the sustainability of rural groundwater services

为目前无法获得安全用水的约3.44亿非洲人提供改善的地下水资源，对于改善健康、减少贫困和提高家庭对气候变化的适应能力的许多发展努力至关重要。根据千年发展目标，在扩大水覆盖范围方面取得了相当大的进展，据估计，1990年至2010年期间，3.22亿人获得了安全用水。然而，越来越多的人担心，基于假定的功能和服务水平的覆盖统计可能会掩盖服务可持续性的实际问题。已发表的证据，尽管支离破碎且方法不明确，表明可能有30%或更多的地下水水源在建设的几年内“失效”。业内专业人士多年来一直知道这些问题，但对投资和基础设施的重视，而不是长期效果，转移了人们对设施建成后实际情况的关注。尽管这个问题的规模被认为是巨大的，但也很少有证据表明来源为什么会失败。在缺乏关于失败的程度和原因的系统证据的情况下，捐助者和国家政府冒着重复错误和实现低物有所值的风险。大量失败水源的投资累积损失可能是巨大的——数千万美元——如果人们暂时或永久地恢复使用未经改善的水源，就会失去公共卫生和生计方面的好处。依赖地下水的农村水资源衰竭的原因是复杂的，供水衰竭可能是许多相互关联的促成因素的结果，包括水需求的变化、降雨量的减少、不适当的工程和治理。在不同的环境中，这些因素对源失效的重要性和贡献有显著不同。揭开供应失败的原因需要了解(1)地下水条件和趋势，(2)供水点选址，设计和施工，(3)融资，管理和支持安排，以及(4)需求压力和峰值。这个研究项目旨在解决非洲农村地下水供应失败的关键知识和证据差距，并通过开发一种诊断系统失败原因的可靠方法，这可以用于为围绕建设新的供水点以及维护和修复现有供水点的决策提供信息。该项目将把该方法应用于乌干达的一项试点研究，以建立关于地下水供应和水源失效原因的第一个系统证据基础。这将是对失败原因的第一次严格评估，研究的产出将大大提高捐助者和国家政府以及非政府组织的能力，以确保在水方面的投资能够持久地获得安全饮用水。这项研究将为依赖不断下降的地下水供应的贫困农村社区带来实际利益，特别是作为主要取水者的妇女和儿童。只有提供有关问题规模及其根本原因的可靠证据，才能解决问题。

Extending access to improved groundwater sources for the estimated 344 million Africans currently without access to safe water is fundamental to many of the development efforts to improve health, reduce poverty and increase the resilience of households to climate change. Considerable progress has been made in increasing water coverage under the Millennium Development Goals (MDGs), with estimates indicating 322 million people have gained access to safe water over the period 1990 to 2010. However, there is growing concern that coverage statistics based on assumed levels of functionality and service may conceal real problems of service sustainability. The published evidence, albeit fragmented and methodologically unclear, suggests that perhaps 30% or more of groundwater-based water sources 'fail' within a few years of construction. Sector professionals have known about such problems for years, but the emphasis on investment and infrastructure, rather than long term results, has diverted attention away from what actually happens to facilities once built. Despite the suggested scale of the problem, there is also very little evidence on why sources fail. In the absence of systematic evidence on the extent and causes of failure, donors and country governments risk repeating mistakes and achieving poor value for money. The cumulative loss of investment in large numbers of failed sources could be enormous - tens of millions of dollars - and public health and livelihood benefits are lost if people revert to unimproved water sources on a temporary or permanent basis. The causes of groundwater-dependent rural water failure are complex, and supply failure is likely to be the result of a number of inter-related contributory factors, ranging from changes in demand for water, reduction in rainfall, inappropriate engineering, and governance. These factors will have significantly different importance and contribution to source failure in different settings. Unravelling the causes of supply failure requires an understanding of (1) groundwater conditions and trends, (2) water point siting, design and construction, (3) financing, management and backstopping arrangements, and (4) demand pressures and peaks. This research programme sets out to address the key knowledge and evidence gap surrounding rural groundwater supply failure in Africa, and by developing a robust methodology for diagnosing why systems fail, which can be used to inform decisions around the construction of new water supply points, and the upkeep and rehabilitation of existing ones. The project will apply the methodology to a pilot study in Uganda to develop the first systematic evidence base on causes of groundwater supply and source failure. This will be the first rigorous assessment of the causes of failure, and the outputs of the research will significantly increase the capacity of donors and country governments, and NGOs, to ensure investment in water achieves lasting access to safe drinking water. The research will lead to realised benefits to the poor rural communities reliant on failing groundwater-based water supplies, particularly women and children as the main water collectors. Only by providing reliable evidence of the scale of the problem, and its underlying causes, can the problem be addressed.