City of San Diego: Indirect Potable Reuse

Following Surfrider’s and San Diego Coastkeeper’s 2002 lawsuits against the City of San Diego for improperly approving a waiver of secondary sewage treatment at its Point Loma Wastewater Treatment Plant, the environmental organizations entered into a multi-pronged settlement that required, among other things, that the City conduct a study of all available opportunities to increase water recycling within its service area. The environmental groups primarily sought to resurrect a previously failed Indirect Potable Reuse (IPR) project which would result in highly treated sewage being combined with San Diego’s raw water from the Colorado River or San Francisco Bay Delta. Sometimes called “toilet to tap,” the environmental groups nonetheless sought to re-initiate discussion among community leaders and citizens about the benefits of such a local source of water. After the production of a comprehensive Water Reuse Study involving numerous meetings, dozens of community leaders, and a technical advisory committee, the City Council finally took action. On October 29, 2007 the San Diego City Council approved a resolution authorizing the beginning steps of an Indirect Potable Re-Use (IPR) project in San Diego. The City Water Department was directed by the Council to: • Execute a one-year demonstration project of the Advanced Water Treatment (AWT) process to begin July 1, 2008; • Conduct a current flow and detention study at the San Vicente Reservoir to ensure that any treated sewage added to the inflow would remain in the reservoir for at least one year before being processed for potable purposes.; • Perform an independent energy and economic analysis for all water supply options in the Long-Range Water Resources Plan; and, • Conduct community education and outreach. The serious consideration and possible implementation of IPR would be an enormous victory for the environment. Not only would this new source of water be much more environmentally friendly than options such as desalination or imported water, it would also result in reduced flows of treated sewage into the Pacific Ocean via the Point Loma Ocean Outfall.

Clean Water