Preparing for Climate Change in California’s East Bay Municipal Utility District
The East Bay Municipal Utility District (EBMUD) has developed mitigation and adaptation strategies to address the effects of climate change on water resources in the San Francisco Bay Area. These strategies include reducing greenhouse gas emissions, incorporating climate change into planning efforts, and creating a monitoring and response plan to inform planning for infrastructure and water quantity and quality in the face of climate change.
Located in the San Francisco Bay Area of California, the EBMUD serves approximately 1.3 million consumers in over 20 cities. The District obtains over 95% of its drinking water supply from the Mokelumne River; to supplement this supply, the District, along with the Sacramento County Water Agency (SCWA), is investing in the Freeport Regional Water Project, which will divert water from the Sacramento River and bring it into the East Bay system.
Climate change impacts of concern to the water system include loss of snowpack, changes in freshwater flow patterns, changes in precipitation levels, and increased temperatures. The District is working to stay up-to-date on the science and assessment of climate change effects in the Mokelumne and East Bay watersheds, and examining these impacts in terms of consequences for water supply and demand and potential vulnerabilities of the system’s infrastructure.
Many of the assessments have been conducted with the support of the Lawrence Livermore National Lab. These vulnerability assessments include:
- hydraulic and hydrologic modeling to determine what might happen to river flow;
- water temperature modeling to determine effects on fisheries and water quality; and
- investigating the reliability of infrastructure to deal with rising sea levels and water supply.
The last assessment is of particular concern because the aqueducts running from the Mokelumne River cover about 90 miles of the Bay Delta, which is currently below sea level and protected by levees; the aqueducts and levees are therefore both highly vulnerable to sea level rise. The long-term solution is to bury the aqueducts under the Bay Delta for a 10 to 15 mile stretch; this construction would be very expensive (~$500 million) but may be necessary. Less expensive and more short-term solutions that EBMUD is employing include:
- the addition of climate change to the strategic plan in 2008, which guides EBMUD’s planning efforts;
- establishment of a climate change committee comprised of five working groups (Science and Assessment; Impacts, Vulnerability, and Adaptation; Mitigation; Legislation and Regulations; and Public Outreach);
- creation of a monitoring and response plan to deal with vulnerabilities and impacts; and
- creation of a long-term water supply planning effort built out to 2040 that incorporates uncertainty.
Outcomes and Conclusions
The EBMUD has already taken steps to plan for and adapt to climate change. The District plans to continue its monitoring and assessment activities in order to determine vulnerabilities and identify needed actions to protect the water supply system.
Gregg, R. M. (2010). Preparing for Climate Change in California's East Bay Municipal Utility District [Case study on a project of the East Bay Municipal Utility District and the Lawrence Livermore National Lab]. Product of EcoAdapt's State of Adaptation Program. Retrieved from CAKE: http://www.cakex.org/case-studies/preparing-climate-change-california’... (Last updated July 2011)