Science Inventory

Holistic Analysis of Urban Water Systems in the Greater Cincinnati Region: (1) Life Cycle Assessment and Cost Implications

Citation:

Xue, X., S. Cashman, A. Gaglione, J. Mosley, L. Weiss, Cissy Ma, J. Cashdollar, AND J. Garland. Holistic Analysis of Urban Water Systems in the Greater Cincinnati Region: (1) Life Cycle Assessment and Cost Implications. Water Research X. Elsevier B.V., Amsterdam, Netherlands, 2:100015, (2019). https://doi.org/10.1016/j.wroa.2018.100015

Impact/Purpose:

To elucidate a bigger picture of energy, resource and cost distributions in a typical urban centralized water system while providing insights for more sustainable holistic system managements. Urban water and wastewater utilities are striving to improve their environmental and economic performances due to multi-challenges such as increasingly stringent quality criterion, aging infrastructure, constraining financial burden, growing urban population, climate challenges and dwindling resources. Growing needs of holistic assessments of urban water systems are required to identify system-level cross-domain solutions. This study evaluated the life cycle environmental and economic impacts of urban water and wastewater systems with two utilities in Greater Cincinnati region as a case study. The scope of this study includes the entire urban water and wastewater systems starting from raw water acquisition for drinking water to wastewater treatment and discharge. The detailed process-based life cycle models were developed based on the datasets provided by local water and wastewater utilities. The life cycle assessment indicated that the operation and maintenance of drinking water distribution and wastewater treatment stages were the dominating contributors for energy consumption (70%) and global warming potential (78%). Wastewater discharge from the wastewater treatment plant contributed to more than 80% of the total eutrophication potential. The cost analysis determined that labor and maintenance cost (19%) for wastewater collection, and electricity cost (13%) for drinking water distribution were major contributors. Sensitivity analysis showed that the life cycle environmental results were more sensitive to the choice of the electricity mixes and electricity consumption than the rest of input parameters such as chemical dosages, and infrastructure life time. This is one of the first comprehensive studies of urban water systems as a whole using real case data. It elucidates a bigger picture of energy, resource and cost distributions in a typical urban centralized water system while providing insights for more sustainable holistic system managements.

Description:

Urban water and wastewater utilities are striving to improve their environmental and economic performances due to multi-challenges such as increasingly stringent quality criterion, aging infrastructure, constraining financial burden, growing urban population, climate challenges and dwindling resources. Growing needs of holistic assessments of urban water systems are required to identify system-level cross-domain solutions. This study evaluated the life cycle environmental and economic impacts of urban water and wastewater systems with two utilities in Greater Cincinnati region as a case study. The scope of this study includes the entire urban water and wastewater systems starting from raw water acquisition for drinking water to wastewater treatment and discharge. The detailed process-based life cycle models were developed based on the datasets provided by local water and wastewater utilities. The life cycle assessment indicated that the operation and maintenance of drinking water distribution and wastewater treatment stages were the dominating contributors for energy consumption (70%) and global warming potential (78%). Wastewater discharge from the wastewater treatment plant contributed to more than 80% of the total eutrophication potential. The cost analysis determined that labor and maintenance cost (19%) for wastewater collection, and electricity cost (13%) for drinking water distribution were major contributors. Sensitivity analysis showed that the life cycle environmental results were more sensitive to the choice of the electricity mixes and electricity consumption than the rest of input parameters such as chemical dosages, and infrastructure life time. This is one of the first comprehensive studies of urban water systems as a whole using real case data. It elucidates a bigger picture of energy, resource and cost distributions in a typical urban centralized water system while providing insights for more sustainable holistic system managements.