Project #4962

Identifying the Amount of Wastewater That Is Available and Feasible to Recycle in California

Principal Investigator
Research Manager
Ms. Stephanie Fevig, PE
University of California at Davis
Reuse: Potable


The purpose of project 4962 was to identify the amount of treated municipal wastewater available for recycled water production in California now and projected into the future considering factors such as the required minimum instream flows, water quality, proximity to potential water reuse sites, and cost.
Despite continuing development and increased recognition of the importance of recycled water in water resources management, the volume of recycled water recorded in California has been well under the recycled water goal of 1.5 million ac-ft set in the 1980s. This project was conducted to understand the amount of recycled water potentially available for beneficial uses and to inform the development of realistic recycled water goals.
Findings highlight the fact that traditional non-potable water reuse applications will likely provide lower cost reuse opportunities for limited total volumes, while indirect and direct potable water reuse options will be essential water reuse strategies to approach the technically feasible total volumetric water reuse rate of 2.53 Mac-ft/y, consisting of 0.7 Mac-ft/y of existing reuse and 1.83 Mac-ft/y of potential new water reuse capacity. This report provides a high-level view of opportunities and limitations from which audiences will learn factors that may affect the feasibility of achieving high recycled water goals.
Research Partner: California State Water Resources Control Board. Published in 2023.