WALNUT CREEK, Calif. — The California Urban Water Agencies’ (CUWA) newly released white paper, “Adapting to Change: Utility Systems and Declining Flows,” provides decision makers, water/wastewater system managers, and other stakeholders an understanding of the impacts of declining system flows and how utilities are adapting to these circumstances.

Brown and Caldwell’s Chief Technical Officer Cindy Paulson and Water Reuse Leader Wendy Broley helped bring the paper together.

“Wise water use is a fundamental component of CUWA’s mission and an important part of our agencies’ long-term water supply reliability efforts for sustainably meeting future water demands. And yet, within the interconnected urban water cycle, rapidly declining flows can potentially impact water, wastewater, and recycled water systems.”
CUWA Executive Director Cindy Paulson

During the recent historic drought, Californians responded to the Governor’s call for emergency statewide water use reductions. And the corresponding reduction in water demands brought to light some unintended consequences of declining flows that have a ripple effect throughout systems within the urban water cycle.  “Our goal with this white paper is to better understand the system-wide impacts of increased conservation and water use efficiency so that decision makers are better informed as they address California’s current and future water challenges,” said Broley, who also serves as a CUWA staff engineer.

CUWA’s white paper was developed through a partnership with California Association of Sanitation Agencies (CASA), the Water Research Foundation (WRF), WateReuse California, and the California Water Environment Association (CWEA). The white paper summarizes information from several resources, including:

• A literature review to gain a foundational understanding of what impacts utilities may be experiencing because of declining flows.
• A high-level survey to determine the level and range of observed impacts in California.
• One-on-one interviews and developing case studies to illustrate the broad range of issues agencies are experiencing and their associated impact.

“It is interesting how water use reductions, and the subsequent declining flows are impacting agencies throughout California. Our survey showed that 50% of respondents did in fact experience impacts on their drinking water, wastewater, or recycled water infrastructure,” said City of San Diego External Water Policy Program Manager, Cathy Pieroni. Since the completion of the white paper, CUWA has received multiple requests from utilities interested in responding to the survey with observations and experiences of their own.  As a result, CUWA has agreed to keep the survey open for those that would still like to respond.  CUWA will incorporate the updated results in outreach materials, such as presentations and/or a future article.

The white paper can be accessed on CUWA’s website at: http://www.cuwa.org/pubs/CUWA_DecliningFlowsWhitePaper_11-28-17.pdf

The survey can be accessed here: https://www.surveymonkey.com/r/decliningflows