A Framework for the Economic Assessment of a More Sustainable Wastewater Management System

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Conference Proceeding

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Blackwater and greywater are transported through the same sewage pipe in the traditional wastewater network in a city. This mixture turns both the blackwater and greywater into blackwater, which needs to go through extensive treatment processes before being discharged. On the other hand, greywater can be reused for numerous purposes, even after basic filtration. Fortunately, there are varieties of household greywater reuse systems (GWS) available in the market that can make good use of this resource by reusing this massive amount of generated greywater with its internal filtration or UV disinfection unit. This stops this massive amount of greywater from leaving the household, eventually reducing the sewage bill drastically. Furthermore, the lower volume of blackwater also allows for smaller sewer pipes and reduces the number of wastewater treatment plants required in a city. These reduced wastewater treatment plants will result in a significant drop in cost per capita for the city’s population, as well as less environmental impact. Altogether, it can be affirmed that the outputs of this wastewater management system will satisfy the economic, environmental, and social concerns for sustainable cities. However, dual plumbing and greywater system installation, operation, maintenance, and replacement (OMR) costs will initially add new expenses to the bills. Therefore, an economic assessment is necessary to verify that the assumed savings can significantly outweigh this cost, resulting in a net benefit. This study provides the framework for conducting this economic assessment of implementing this system. The framework will act as a guideline to conduct a thorough economic assessment of various similar sustainable design concepts for sustainable cities.


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Publication Title

Proceedings of the Canadian Society of Civil Engineering Annual Conference 2022