Date of Graduation

Spring 5-20-2016

Document Type


Degree Name

Master of Science in Environmental Management (MSEM)


College of Arts and Sciences


Environmental Management

First Advisor

Tracy Benning



This paper examines the challenges and economic feasibility of implementing grey water recycling systems at a citywide scale. Past and present conditions of fresh water scarcity are discussed, and how scarcity will be exacerbated by climate change. Previous technological developments and initiatives are discussed, and how they are implemented to reduce fresh water scarcity. Challenges, examples and costs of implementing grey water systems are detailed; in general results indicate that large projects (such as apartment complexes and multistory buildings) are only economically feasible (as opposed to single-family homes), decentralized (on-site) systems also appear to be more economically feasible due to cost savings of energy and piping required to convey grey water and waste water for treatment and installing a grey water system in new construction is less costly than retrofitting a building. Additional costs associated with determining the economic feasibility of grey water systems are nuanced, for example water rates make a large difference on the payback period of the project and lifestyle of the occupant (differing water amount and detergent uses). The average project cost ranged from $447,289 to $4,411, payback period ranged from 10-16 years and only a positive Net Present Value (NPV) was determined for a multistory building. For a city such as San Francisco, implementing grey water systems in single-family homes and multistory buildings would cost approximately $1.8 billion dollars