Environmental engineering research on decentralized, biological remediation of wastewater through the creation of treatment wetlands has advanced dramatically in the last decade. Treatment wetlands can effectively meet secondary treatment standards for total suspended solids and biological oxygen demand. Certain designs can achieve tertiary quality for ammonia, nitrates, and pathogenic bacteria. At costs equal to or lower than conventional systems, treatment wetlands can rejuvenate wastewater effluent generated by institutions, subdivisions, and small towns in diverse climates. In addition to providing ecosystem services relating to wastewater remediation, these site-based multifunctional landscapes also enhance biological diversity and provide open space values relating to scenic quality, recreation, and education. When aligned with ecosystem corridors, treatment wetlands become part of larger scale multi-functional landscapes that provide green infrastructure to guide development patterns at the regional scale. This paper examines the ability of a decentralized sequence of treatment wetlands located within public open space to improve ecosystem health and provide ecosystem service benefits to society at multiple geographic scales.