Diversifying. San Francisco s Water Supply. It s hard to imagine life without water we depend on it every day. Hetch Hetchy Regional Water System

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1 Diversifying San Francisco s Water Supply Hetch Hetchy Regional Water System The San Francisco Public Utilities Commission (SFPUC) delivers water through the Hetch Hetchy Regional Water System to 2.5 million customers throughout the Bay Area. The system brings water directly from the Hetch Hetchy Reservoir in Yosemite National Park and protected local watersheds to customer businesses and homes. With portions of the 167-mile delivery system crossing three seismically active faults, our water supply is vulnerable to a major earthquake as well as other emergencies that could severely disrupt drinking water supplies. It s hard to imagine life without water we depend on it every day. San Francisco Bay Area residents and businesses have long enjoyed some of the nation s highest-quality drinking water. We must protect this vital resource from possible disruption caused by drought, climate change and natural disaster, and we are partnering with neighboring Bay Area water providers to diversify our water supply. And, while San Francisco resident and business demand for water is among the lowest in all of California, we can do more. The future economic vitality, public health and safety of the San Francisco Bay Area depend on making these critical water supply investments now. Together, we can help ensure a reliable water supply for generations to come.

2 Conservation Using Water Wisely Conservation Promoting the efficient use of water through education, assistance and incentive programs. Conservation is a key way to manage our water supply. California is a dry state, and no city is immune to the challenges of meeting the demands of growing populations with a limited water supply. Water Conservation Programs We assist all types of customers residential, commercial, and institutional to help them understand their water use and identify ways to conserve. This includes coordination with City departments to increase water-use efficiency at City facilities. While customers have made great strides to conserve water, considerable opportunities to save water remain. Program highlights include: Financial incentives for installation of high-efficiency toilets, urinals and clothes washers Free indoor and landscape efficiency audits for residential, commercial and municipal customers Distribution of free water-efficient plumbing devices, including showerheads, aerators, leak tests and other items Direct installation of high-efficiency toilets for low-income customers through our Community Assistance Program (CAP) Free water-wise gardening classes School education programs Informational materials and presentations Implementation of local ordinances to improve plumbing fixtures and landscape irrigation efficiencies Conservation Goals We have been implementing conservation activities for over 20 years to help ensure that future water demands can be supported. We are committed to reducing the amount of water imported today, and into the future. Through active conservation and plumbing code requirements, we anticipate reducing our water demands by 14 million gallons per day (mgd) by 2018 and 23 mgd by 2035.

3 TextText Groundwater A Natural Source of Water Supply Groundwater Groundwater also known as well water is a renewable source of naturally occurring water that is found beneath the ground s surface. More than 100 years ago, groundwater was used as one of San Francisco s primary drinking water supplies. As surface water (such as rain) seeps into the ground, it passes through voids between soil and rock particles and collects underground. This underground reservoir (called an aquifer) can be managed just as we manage our surface water supplies. The Westside Groundwater Basin in San Francisco is a large aquifer extending from Golden Gate Park southward through San Bruno. The cities of South San Francisco, Daly City, and San Bruno have been pumping groundwater from this source for drinking water and other uses for more than 60 years. LEGEND Groundwater Use in San Francisco Drought conditions and water system vulnerability due to seismic activity or emergencies underscore our need to maximize the use of local water sources. Building groundwater wells in San Francisco can provide a safe and reliable source of drinking water. Our proposal is to install up to 6 supply wells to pump groundwater for use as drinking water. These groundwater wells will produce and average of 4 million gallons of drinking water per day. Treated groundwater will enter the municipal drinking water system after it is blended with our Regional System water in 2 of our local reservoirs. The resulting water blend, containing a small percentage of groundwater, will be distributed throughout the City. Blending will ensure continued high quality and no change in taste or odor. Projected Distribution of San Francisco Groundwater Blend SAN FRANCISCO BAY Sunset/Sutro Reservoir Distribution: Groundwater Blend Other Reservoir Distribution Parks and Open Spaces PACIFIC OCEAN SAN MATEO COUNTY

4 Recycled Water A Reliable and Sustainable Choice Recycled Water Recycled water is wastewater that has undergone extensive treatement that makes it safe and suitable for a number of uses. Water is too valuable to be used just once. Recycled water is used by more than 1,600 sites in 11 states, including 160 cities in California, for applications such as landscape irrigation, toilet and urinal flushing, commercial and municipal cooling, decorative fountains, lake filling, and other commercial, municipal and industrial uses. Maximizing the use of this renewable local resource makes sense. In San Francisco, recycled water will replace the use of groundwater and potable water currently being used for irrigation and toilet flushing. Recycled water will also help us make more efficient use of our water supplies, and reduce the amount of treated wastewater discharged into the Pacific Ocean and San Francisco Bay. We propose to use approximately 4 million gallons per day (mgd) of recycled water. San Francisco s Recycled Water Projects The Harding Park Recycled Water Project will bring recycled water from the North San Mateo County Sanitation District in Daly City to irrigate Harding Park Golf Course. Construction is scheduled for completion in The Pacifica Recycled Water Project will bring recycled water from the Calera Creek water recycling facility in Pacifica to irrigate the City-owned Sharp Park Golf Course as well as other landscape areas in Pacifica. Construction is scheduled for completion in The proposed Westside Recycled Water Project would provide water for irrigation of Golden Gate Park (including the Panhandle), Lincoln Park Golf Course and the Presidio Golf Course. It would also provide water for the ornamental lakes in Golden Gate Park and for toilet flushing and irrigation at the California Academy of Sciences. The proposed Eastside Recycled Water Project would to save drinking water that would otherwise be used for non-drinking purposes such as irrigation and toilet flushing in the eastern part of San Francisco.

5 Graywater Effective Reuse of Water Graywater Graywater is water from washing machines, showers, bathtubs and bathroom sinks that may contain some soap but is clean enough to water trees and shrubs. Untreated graywater can be used for sub-surface irrigation. The simplest method of graywater irrigation is a laundry-to-landscape system. This system involves attaching a 3-way valve to the washing machine hose, which allows the water from the washing machine to go directly to the yard for sub-surface irrigation. The valve can easily switch back to the sewer when there is no need to irrigate. Laundry-to-Landscape Pilot Graywater Program Our Laundry-to-Landscape Pilot Graywater Program offers a subsidy toward the cost of a laundry-tolandscape graywater kit. Qualifying single-family and two-unit residential properties are eligible to participate. In addition to the low-cost laundry-tolandscape kit, participants attend a free installation workshop, receive in-home advice and technical assistance from a graywater expert on installing their system, have access to a tool-lending library, and receive a free copy of the Graywater Design Manual for Outdoor Irrigation. San Francisco Graywater Design Manual for Outdoor Irrigation We have developed a technical resource for homeowners and professionals who want to install graywater systems for outdoor irrigation in San Francisco. This manual includes a detailed step-by-step process for designing and installing a laundry-to-landscape system, as well as the basic steps for designing and installing branched-drain and pumped systems. In it you will learn the benefits of graywater systems, when and where to install them, and the permit, operation and maintenance requirements.

6 Rainwater Harvesting Don t Let Good Water Go to Waste Rainwater Rainwater harvesting is the practice of collecting and using rainwater from hard surfaces such as roofs. It is an age-old technology that is growing in popularity as people look for ways to use water resources more wisely. Communities in ancient Rome were designed with individual cisterns and paved courtyards, which captured rainwater to augment supply from the city s aqueducts. Until recently, urban areas served by municipal water have tended to overlook rainwater as a water resource. San Francisco would like to change that by raising awareness about rainwater harvesting and promoting its use. Harvested rainwater is most commonly used for outdoor irrigation. We offer discounts on rain barrels and cisterns. Why Harvest Rainwater? When you install a rainwater harvesting system at home, you are helping to maintain the health of San Francisco s urban watershed in many ways. By harvesting rainwater you: Keep relatively clean water out of the combined sewer system and make it available for use Reduce the energy and chemicals needed to treat stormwater in San Francisco s combined sewer system, and the energy expended transporting water from far away Reduce the volume and peak flows of stormwater entering the sewer, thereby minimizing flooding and combined sewer discharges Reduce the volume of potable water used for non-potable applications such as irrigation Desalination A Regional Response to Water Needs Desalination is the process of removing salts from ocean, bay, or estuary water to produce fresh drinking water. The Bay Area Regional Desalination Project is a partnership between some of the Bay Area s largest regional water agencies the San Francisco Public Utilities Commission, Contra Costa Water District, East Bay Municipal Utility District, Santa Clara Valley Water District and Zone 7 Water Agency. Through this regional partnership, we are currently investigating the potential for desalination as a regional water supply source. For more information on our water supply program, call us at (415) or visit sfwater.org.