Uneven access to water and wastewater infrastructure is shaped by local governance. A substantial number of U.S. households lack adequate access and the U.S. is one of the few countries with large populations living outside of city bounds, in unincorporated areas. Few studies address how infrastructure services and local governance are intertwined at a regional scale. We examine the connection between incorporation status and access to centralized infrastructure, using negative binomial regression. A novel dataset informs this analysis, comprised of 31,383 Census block groups located in nine states representing over 25% of the national population. We find evidence that inequities in access are associated with unincorporated status and poverty rates. Sewer coverage rates are significantly lower for unincorporated communities in close proximity to municipal boundaries. Infrastructure equity could be improved by targeting high-poverty unincorporated communities, addressing challenges with noncontiguous service areas, and strengthening regional water planning and participatory governance.

水和废水基础设施的不均衡是受地方治理的影响。大量美国家庭缺乏足够的访问，美国是少数几个拥有大量人口居住在城市边界以外的非建制地区的国家之一。很少有研究讨论基础设施服务和地方治理如何在区域范围内交织在一起。我们使用负二项式回归检查公司注册状态与获得集中式基础设施之间的联系。一个新的数据集为这项分析提供了信息，该数据集由位于 9 个州的 31,383 个人口普查区块组组成，占全国人口的 25% 以上。我们发现证据表明，入学机会上的不平等与非法人身份和贫困率有关。靠近市政边界的非建制社区的下水道覆盖率明显较低。可以通过针对高度贫困的非法人社区、解决不连续服务区的挑战以及加强区域水规划和参与式治理来改善基础设施公平。