Like many islands worldwide, Santa Cruz, the most populated of Ecuador's Galápagos Islands, has limited resources to provide safe drinking water to an increasing number of inhabitants and tourists. Currently, households receive brackish water at their tap, which is rationed to a few hours per day. Insufficient recovery of water supply costs is an impediment to improving water services. Against this backdrop, we implemented a contingent valuation survey to investigate whether households are willing to pay for improved water services. Using split-sample scenarios that allow for scope and part-whole tests, we elicited household preferences for three improvements: 1) uninterrupted water supply, 2) drinkable tap water, and 3) combining both. Our estimation results indicate that households are willing to pay for safe drinking water. Conversely, our willingness-to-pay estimates suggest that households are indifferent about improvements of service reliability unless water quality is improved as well. The median willingness to pay for concurrent improvements of system reliability and water quality is estimated at approximately $36/month, about 2.1% of average monthly household income. This study has policy implications as it demonstrates that households deem system reliability and water quality as complementary improvements.

像世界上许多岛屿一样，厄瓜多尔加拉帕戈斯群岛人口最多的圣克鲁斯（Santa Cruz）资源有限，无法为越来越多的居民和游客提供安全的饮用水。当前，家庭的自来水收到微咸水，每天分配给几个小时。供水成本回收不足是改善供水服务的障碍。在此背景下，我们实施了一项或有估值评估，以调查家庭是否愿意为改善的水服务付费。使用允许进行范围和部分整体测试的分割样本方案，我们得出了三项改进的家庭偏好：1）不间断的供水，2）饮用自来水，以及3）两者结合。我们的估计结果表明，家庭愿意为安全的饮用水付费。反过来，我们的支付意愿估计值表明，除非水质也得到改善，否则家庭对提高服务可靠性并不关心。愿意同时改善系统可靠性和水质的中位数支付意愿约为36美元/月，约占家庭平均每月收入的2.1％。这项研究具有政策意义，因为它表明家庭认为系统的可靠性和水质是补充性的改进。