The Stanford Woods Institute hosted a dialogue on resource recovery from wastewater - specifically, how systems for wastewater management and water reuse should be defined for the San Francisco Bay Area in the 2020s. The dialogue brought together consultants, researchers, water quality agencies and government and industry leaders to inform planning efforts and align research with those efforts. Participants at the dialogue developed a "Wastewater as a Resource" vision statement for the Bay Area. On Oct. 28, 2010, the executive board of the Bay Area Clean Water Agencies (BACWA) unanimously passed a resolution adopting that vision statement.

Dialogue Objectives

Discussion focused on state-of-the-art technologies for water reuse and energy recovery from wastewater; and ideas for use of reclaimed water for ecosystem restoration and non-potable reuse applications, extraction of renewable energy, use of nutrients and financing and development of distributed and centralized wastewater treatment systems around the Bay. Workshop outcomes helped promote investments to revitalize Bay Area water and wastewater infrastructure, improve the stability of Bay Area ecosystems, increase the security and reliability of freshwater supplies, decrease dependence upon imported freshwater, and increase renewable energy generation. The expected solutions will convert current liabilities (e.g., energy required for wastewater treatment) into assets (e.g., energy from wastewater treatment). 

The Need

Forty wastewater treatment plants protect the water quality of the San Francisco Bay. These plants underwent massive redesign and reconstruction in the late 60's and early 70's to add secondary treatment that today provide efficient removal of waste organic matter from wastewater discharged to the Bay. Also important was the emphasis in the 1980's and 1990's on control of toxic contaminants, a goal that was mostly achieved through better pre-treatment technology and regulation and the (possibly-related) decline of American chemical manufacturing. 

We are now at a deciding moment. All of the treatment plants protecting the Bay Are at or exceeding their design lives. All are therefore involved in or preparing for "Master Planning" that will determine the future course of wastewater management in the Bay Area. This is an enormous challenge and involves many operators, consultants, government agencies, and non-profit organizations. 

Adding to this complexity are the constantly evolving goals of wastewater treatment. Particularly in the arid West, increased population pressure has increased the need for fresh water. Standards of treatment are changing. Many environmental groups now call for re-definition of secondary treatment to include specific standards for nutrients. New understanding of the microbial ecology of wastewater treatment could result in dramatic improvements in nutrient management and energy recovery, converting treatment plants into resource recovery centers that also contribute to reduced carbon emissions. As a result of this mixture of past accomplishments, new needs, and new technology, public demands on wastewater managers are likely to shift from solely preventing environmental degradation to incorporating wastewater into the entire life cycle assessment process of our cities.

Related links

http://www.stanford.edu/group/evpilot/