Case Study: Water and Wastewater Utilities Planning for Climate Change EAST BAY MUNICIPAL UTILITY DISTRICT Background The East Bay Municipal Utility District (EBMUD) provides high-quality drinking water to 1.4 million customers in the San Francisco Bay Area. EBMUD's primary water supply comes from the Mokelumne watershed in the Sierra Nevada Mountains, where it has water rights for up to 325 million gallons per day (MGD). In dry years, EBMUD can use up to 100 MGD from the Sacramento River to augment its Mokelumne watershed supplies. The water treatment and distribution system consists of six water treatment plants, nearly 400 distribution facilities, and approximately 4,200 miles of distribution pipeline. EBMUD also has comprehensive water conservation and water recycling programs as part of its water supply portfolio. Climate Threats For EBMUD, drought and sea level rise are two of the primary climate threats. Based on historic hydrology, three out of ten years are dry in the Mokelumne watershed. Climate change is expected to increase hydrologic variability and result in more frequent and intense droughts. EBMUD's raw water system is comprised of a complex network of reservoirs, aqueducts (large pipes), and pump stations. Integral to the raw water system are the Mokelumne Aqueducts that cross 82 miles of terrain that includes the Sacramento-San Joaquin Delta. Portions of the Delta where the aqueducts cross are currently below mean sea level and protected by a series of levees that are vulnerable to sea level rise. Planning Process To plan for its water supply, EBMUD developed a Water Supply Management Program (WSMP), which is a long-term water supply plan to identify and recommend solutions to meet dry year water needs through the year 2040. The WSMP is a robust plan for an uncertain future including the effects of climate change. To understand the potential impact of climate change, EBMUD conducted a sensitivity analysis where variations in water demand, drought frequency, and the volume and timing of runoff from the Mokelumne River were modeled. EBMUD used the U.S. Environmental Protection Agency's Climate Resilience and Awareness Tool (CREAT) to communicate the climate change impacts identified in the WSMP. Adaptation Measures EBMUD has adopted a number of adaptation and mitigation measures to deal with climate change and its potential impacts to water supply and sea level rise. See the table below for adaptation and mitigation measures that have been adopted by EBMUD. East Bay Municipal Utility District Case Study— Page 1 xvEPA ------- Case Study: Water and Wastewater Utilities Planning for Climate Change TYPE ADAPTIVE MEASURES Water supply resilience Supplemental water supply from the Sacramento River Customer water rationing Water conservation and water recycling Water transfers Regional desalination Greenhouse gas emissions reductions Eliminate indirect greenhouse gas emissions by 2040 (i.e., electricity use) Reduce direct greenhouse gas emissions by half by 2040 (e.g., fuel use) Sea level rise Maintain a six-month local raw water supply in the event of an aqueduct failure Constructed aqueduct bypass facilities Develop a strategic plan to protect the aqueducts in the Delta Contact Information For more information about EBMUD's climate change adaptation and mitigation activities, visit their website at http://www.ebmud.com/about-us/sustainabilitv/climate-chanqe/. East Bay Municipal Utility District Case Study — Page 2 oEPA Office of Water (4608T) EPA 810-S-16-006 January 2017 ------- |