Individuals experiencing unsheltered homelessness face significant barriers to accessing water, sanitation, and hygiene services, but the risks associated with this lack of access and barriers to service provision have been largely understudied. We analyzed water samples upstream and downstream of three homeless encampments in the San Diego River watershed and interviewed service providers from public and nonprofit sectors to assess local perceptions about challenges and potential solutions for water and sanitation service provision in this context. Water upstream from encampments contained detectable levels of caffeine and sucralose. Escherichia coli concentrations downstream of the encampments were significantly greater than concentrations upstream, but there was no significant change in the concentrations of other pollutants, including caffeine and sucralose. The HF183 marker of Bacteroides was only detected in one sample upstream of an encampment and was not detected downstream. Overall, there was insufficient evidence to suggest that the encampments studied here were responsible for contributing pollution to the river. Nevertheless, the presence of caffeine, sucralose, and HF183 indicated that there are anthropogenic sources of contamination in the river during dry weather and potential risks associated with the use of this water by encampment residents. Interviews with service providers revealed perceptions that the provision of water and sanitation services for this population would be prohibitively expensive. Interviewees also reported perceptions that most riverbank residents avoided contact with service providers, which may present challenges for the provision of water and sanitation service unless trust is first built between service providers and residents of riverine encampments.

中文翻译：

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对河流沿岸营地中无家可归的个人的环境水质和获得水和卫生服务的挑战的评估

遭受无家可归的无家可归的人面临着获得水，卫生和卫生服务的巨大障碍，但是与获取和获取服务的障碍相关的风险在很大程度上已经被研究不足。我们分析了圣地亚哥河流域三个无家可归者营地上游和下游的水样，并采访了公共部门和非营利部门的服务提供商，以评估当地对水和环境卫生服务面临的挑战和潜在解决方案的看法。营地上游的水含有可检测水平的咖啡因和三氯蔗糖。大肠杆菌营地下游的浓度显着大于上游的浓度，但其他污染物（包括咖啡因和三氯蔗糖）的浓度没有显着变化。拟杆菌属的HF183标记仅在一个营地上游的一个样本中检测到了该病毒，而在下游没有检测到。总体而言，没有足够的证据表明此处研究的营地是造成河流污染的原因。然而，咖啡因，三氯蔗糖和HF183的存在表明，在干燥天气期间河中存在人为污染源，并且与营地居民使用这种水有关的潜在风险。与服务提供商的访谈显示，人们认为为该人群提供水和卫生服务的费用将高得令人望而却步。受访者还表示，大多数河岸居民都避免与服务提供商联系，