Wastewater management decision-making: A literature review and synthesis.

Wastewater management decision-making is complicated because of: (1) a complex regulatory structure, (2) the wide variety of conflicting expectations by stakeholders external and internal to the responsible utility, and (2) constrains including regulatory requirements, available technologies and practices, and customer willingness to pay. This review synthesizes the results from over 200 papers published since 2000 and presents a decision-making structure and process which is (1) science and fact-based, (2) reflects sustainability, (3) clear and transparent, (4) inclusive, (5) produces an objective-oriented decision, (6) scalable, (7) repeatable, and (8) efficient. Tools supporting the decision-making process are reviewed, including Multi-Criteria Decision Analysis (MCDA), Data Envelopment Analysis (DEA), Analytic Hierarchy Process (AHP), process modeling, economic assessments, Life Cycle Assessment (LCA), and Social Life Cycle Assessment (SLCA). Ultimately it was determined that engagement of decision-makers and relevant stakeholders to assess their values and preferences, coupled with supporting data and analyses, is necessary to reach a decision that, critically, has the support needed for it to be implemented. The results demonstrate that an understanding of the components of the decision process, coupled with an orderly process, enables good wastewater management decision-making. PRACTITIONER POINTS: A decision-making structure and process leading to the selection of implementable solutions is presented. The process possesses the following attributes: (1) science and fact-based, (2) reflect sustainability, (3) clear and transparent, (4) inclusive, (5) produce an objective-oriented decision, (6) scalable, (7) repeatable, and (8) efficient An extensive summary and analysis of tools supporting the decision process are provided, including Multi-Criteria Decision Analysis (MCDA), Data Envelopment Analysis (DEA), Analytic Hierarchy Process (AHP), process modeling, economic assessments, Life Cycle Assessment (LCA), and Social Life Cycle Assessment (SLCA). The critical role of internal and external stakeholders and differentiating their involvement relative to decision-makers is emphasized.