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41" AND CABRILLO WATER SUPPLY ASSESSMENT AUGUST 21, 2020 Table 4 2015 Projected and Actual Water Supply and Demand (Acre-feet) Land Use Type 2010 UWMP Projected 2015 Demand Actual 2015 Demand Single Family 18,368 14,084 Multi -Family 13,563 10,399 Other (CII) 15,684 12,025 Landscape 185 147 Total 47,800 36,656 Notes: Source: 2010 and 2015 City of Santa Ana UWMPs As shown in Table 4 above, there was a decrease in water supplied to the City in 2015 as to what was predicted to be delivered in the 2010 UWMP (47,800 AF) by approximately 23%. This is likely due to Senate Bill (SB) x7-7 which requires the State of California to reduce urban water use by 20% by the year 2020 as described in more detail below. Similarly, the Executive Order mandated by California Governor Edmund "Jerry' Brown in April 2015 in response to the drought that started in 2011 further required a collective reduction in statewide urban water use of 25% which would also reduce Citywide demands. In addition, UWMPs are typically developed in a conservative manner and tend to overestimate future water demands. Currently, 71% of the City's water supply is from OC Basin groundwater, 28% is from Metropolitan imported water and 1 % is from recycled water. The City's water supply portfolio is expected to change slightly to 70% from OC Basin groundwater, 29% from Metropolitan imported water, and 0.7% recycled water by the year 2040 as discussed in more detail throughout this WSA. Additional details on the strategic management of these resources is explained below. OCWD Groundwater The primary source of water for the City is the Orange County Groundwater Basin ("OC Basin") which is managed by the Orange County Water District (OCWD). The OC Basin underlies the north half of Orange County beneath broad lowlands. The OC Basin covers an area of approximately 350 square miles, bordered by the Coyote and Chino Hills to the north, the Santa Ana Mountains to the northeast, the Pacific Ocean to the southwest, and terminates at the Orange County line to the northwest, where its aquifer systems continue into the Central Basin of Los Angeles County. The OC Basin storage capacity is estimated to be 66 million AF3, of which only a fraction is available for use to prevent against physical damage to the Basin such as seawater intrusion or land subsidence. To ensure the Basin is not overdrawn, OCWD recharges the Basin with local and imported water. The Basin is recharged primarily by four sources including local rainfall, storm and base flows from the Santa Ana River (SAR), purchased Metropolitan imported water; and highly treated recycled wastewater. Basin recharge occurs largely in the following recharge basins that are located in or adjacent to the City of Anaheim: Warner Basin: A 50-foot-deep recharge basin located next to the SAR at the intersection of the 55 and 91 freeways; 3 OCWD Groundwater Management Plan 2015 Update. June 17, 2015. FUSCOE ENGINEERING, INC. 55D-21 13