Leveraging Geospatial Knowledge to Inform Water and Wastewater Management

Abstract

Water and wastewater management are persistent, evolving challenges, and geospatial knowledge provides a unique perspective to understand them. Although there are numerous studies on these topics and great progress in developing effective management strategies, gaps in knowledge remain. These gaps, such as understanding variability in impaired waters or addressing failing wastewater treatment infrastructure, vary spatially. Thus, the overarching objective of this dissertation was to leverage geospatial knowledge to inform water and wastewater management. Three chapters are included in this dissertation. For each chapter a different geospatial technique was utilized to addresses a unique aspect of water quality and wastewater management. Chapter 1 presents a novel spatiotemporal analysis of water quality impairment data (i.e., the 303(d) List) in Alabama and showed that Alabama coastal areas have more impaired waters compared to rest of the state. This manuscript exemplifies how existing water quality can be translated into new accessible insights for water quality managers, the public, and policy makers. In Chapter 2, the first national inventory of onsite wastewater treatment system (OWTS) data was completed. Results revealed that over half of the United States does not have parcel-resolution publicly available OWTS data (59% by area). This highlights the need to bolster open, accessible OWTS data, which are beneficial to inform local communities in decision making and infrastructure planning, academic research investigating related challenges, nonprofits or advocacy groups involved in grant applications or public education, and permitting agencies that seek to build an OWTS dataset. In Chapter 3 spatial optimization was used to model the cost-optimal layout of wastewater infrastructure in Lowndes County, Alabama to inform ongoing wastewater infrastructure improvement efforts. Results suggest that building more centralized infrastructure (i.e., clustered and centralized wastewater treatment systems) would be most cost effective for the county. Other communities could benefit from using this model to inform decision making. Altogether, these projects outline the range geospatial techniques that can be applied to address various water and wastewater challenges. Geographic information systems provide a unique platform to bring together various data and promote systematic analysis to improve management of water and wastewater.