San Francisco Water Power Sewer Services of the San Francisco Public Utilities Commission

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1 San Francisco Water Power Sewer Services of the San Francisco Public Utilities Commission 525 Golden Gate Avenue, 13th Floor San Francisco, CA T F Try February 16, 2017 TO: THROUGH: FROM: Commissioner Anson Moran, President Commissioner Ike Kwon, Vice President Commissioner Ann Moller Caen Commissioner Francesca Vietor Commissioner Vince Courtney Harlan L. Kelly, Jr., General Manage Steven R. Ritchie, Assistant General Manager, Water 5(2"' RE: Water Supply Assessment for the Biosolids Digester Facilities Project 1.0 Summary 1.1 Introduction Under the Water Supply Assessment law (Sections through of the California Water Code), urban water suppliers like the San Francisco Public Utilities Commission (SFPUC) must furnish a Water Supply Assessment (WSA) to the city or county that has jurisdiction to approve the environmental documentation for certain qualifying projects (as defined in Water Code Section (a)) subject to the California Environmental Quality Act (CEQA). The WSA process typically relies on information contained in a water supplier's Urban Water Management Plan (UWMP), and involves answering specific questions related to the estimated water demand of the proposed project. This memo serves as the WSA for the proposed Biosolids Digester Facilities Project ("proposed project"), for use in the preparation of an environmental impact report by the City and County of San Francisco Planning Department (case no ENV, San Francisco Planning Department) Urban Water Management Plan The SFPUC's most current UWMP is the UWMP update for 2015, which was adopted in June The water demand projections in the UWMP incorporated 2012 Land Use Allocation (LUA 2012) housing and employment growth projections from the San Francisco Planning Department. The WSA for a qualifying project within the SFPUC's retail service area may use information from the UWMP. Therefore, the 2015 UWMP is incorporated via references throughout this WSA shown in bold, italicized text. The UWMP may be accessed at Basis for Requiring a WSA for the Proposed Project The proposed project has not been the subject of a previous WSA, nor has it been part of a larger project for which a WSA was completed. The proposed project qualifies for preparation of a WSA under Water Code Section 10912(a) because it would use more water than required by a 500 dwelling unit project (Water Code section 10912(a)(7)). The SFPUC previously determined that a 500 dwelling unit project would create retail water demand of 50,000 gallons per day (gpd) or million gallons per year (gpy). The proposed project is characterized further in Section 1.2. Edwin M. Lee Mayor Anson Moran President Ike Kwon Vice President Ann Moller Caen Commissioner Francesca Vietor Commissioner Vince Courtney Commissioner Harlan L. Kelly, Jr, General Manager

2 Memo to Commissioners WSA for Biosolids Digester Facilities Project February 16, 2017 Page 2 of Conclusion of this WSA In this WSA, the SFPUC concludes that there are adequate water supplies to serve the proposed project and cumulative retail water demands during normal years, single dry years, and multiple dry years over a 20-year planning horizon from 2020 through Additional information on supply sufficiency is provided in Section 4.2, Findings. 1.2 Proposed Project Description The proposed project would construct new solids treatment, odor control, energy recovery, and associated facilities at the SFPUC s Southeast Water Pollution Control Plant (SEP) in San Francisco. Most of the existing SEP solids treatment facilities (including the digesters) are over 60 years old, were not built to withstand the maximum credible earthquake, require significant maintenance, and are operating well beyond their useful life. Newer, more efficient treatment technologies have since been developed that produce a higher quality of biosolids, capture and treat odors more effectively, and maximize biogas production for heat and energy. The proposed project would update and replace the aging SEP solids treatment system. Over the planning period for the proposed project (2045), projected increases in population will increase solids loads from about 187,000 dry pounds per day (2014) to about 280,000 dry pounds per day (2045). The proposed project would be located on portions of the existing SEP property at 750 Phelps Street and 1700 Jerrold Avenue (Block and Lot 5262/009), and the adjacent properties at 1800 Jerrold Avenue (the Central Shops site, Block and Lot 5262/009), and 1801 Jerrold Avenue (the decommissioned Asphalt Plant site, Block and Lot 5281/001). The project site totals approximately 415,000 square feet. The project would involve the demolition of existing structures and installation of the following facilities: Solids Pretreatment Facility Thermal Hydrolysis Process (THS) Anaerobic Digestion THS Cooling Towers Biosolids Dewatering Facility Energy Recovery Facility Biogas Treatment Biogas Storage Waste Gas Burners Solids Odor Control Piping modifications and new pumps for existing pump stations Other ancillary facilities (electrical rooms, transformers, chemical storage, and diesel generator) The proposed project would require construction of new structures totaling less than 215,000 square feet (footprint). No new staff would be needed to operate new facilities. Operation will begin as early as 2023 (startup/commissioning period).

3 Memo to Commissioners WSA for Biosolids Digester Facilities Project February 16, 2017 Page 3 of Water Supply This section reviews San Francisco s existing and planned water supplies. 2.1 Regional Water System See Section 3.1 of the UWMP for descriptions of the Regional Water System (RWS) and Section 6.1 of the UWMP for water rights held by City and County of San Francisco and the SFPUC Water System Improvement Program (WSIP). 2.2 Existing Retail Supplies Retail water supplies from the RWS are described in Section 6.1 of the UWMP. Local groundwater supplies, including the Westside Groundwater Basin, Central Groundwater Sub Basin, and Sunol Filter Gallery Subsurface Diversions, are described in Section of the UWMP. Local recycled water supplies, including the Harding Park Recycled Water Project and Pacifica Recycled Water Project, are described in Section of the UWMP. 2.3 Planned Retail Water Supply Sources The San Francisco Groundwater Supply Project is described in Section of the UWMP. The proposed Westside and Eastside Recycled Water Projects, as well as non-potable water supplies associated with onsite water systems implemented in compliance with San Francisco s Non-potable Water Ordinance (Health Code Chapter 12C), are also described in Section of the UWMP. 2.4 Summary of Current and Future Retail Water Supplies A breakdown of water supply sources for meeting SFPUC retail water demand through 2040 in normal years is provided in Section of the UWMP. 2.5 Dry-Year Water Supplies A description of dry-year supplies developed under WSIP is provided in Section 7.2 of the UWMP. Other water supply reliability projects and efforts that are currently underway or completed are described in Section 7.4 of the UWMP. A breakdown of water supply sources for meeting SFPUC retail water demand through 2040 in multiple dry years are provided in Section 7.5 of the UWMP. For a single dry year, the retail RWS allocation and, thus, the breakdown of water supply sources would be the same as those in a normal year. 3.0 Water Demand This section reviews the climatic and demographic factors that may affect San Francisco s water use, projected retail water demands, and the demand associated with the proposed project. 3.1 Climate San Francisco has a Mediterranean climate. Summers are cool and winters are mild with infrequent rainfall. Temperatures in the San Francisco area average 57 degrees Fahrenheit annually, ranging from the mid-40s in winter to the upper 60s in late summer. Strong onshore flow of wind in summer keeps the air cool, generating fog through September. The warmest temperatures generally occur in September and October. Rainfall in the San Francisco area averages about 22 inches per year and is generally confined to the wet season from late October to early May. Except for

4 Memo to Commissioners WSA for Biosolids Digester Facilities Project February 16, 2017 Page 4 of 7 occasional light drizzles from thick marine stratus clouds, summers are nearly completely dry. A summary of the temperature and rainfall data for the City of San Francisco is included in Table 1. Month Table 1: San Francisco Climate Summary Average Maximum Temperature ( F) Average Minimum Temperature ( F) Average Monthly Rainfall (inches) January February March April May June July August September October November December Annual Average Source: Western Regional Climate Center ( data from two San Francisco monitoring stations (Mission Dolores/SF# and Richmond/SF#047767). 3.2 Projected Growth Projections of population growth in the retail service area through 2040 are presented in Section of the UWMP. The corresponding LUA 2012 projections for housing and employment in San Francisco, which are incorporated into the projected retail water demands, are provided in Appendix E of the UWMP. 3.3 Projected Retail Water Demands For the 2015 UWMP, the SFPUC developed a new set of models that incorporate socioeconomic factors to project retail demands through These models incorporate the latest housing and employment projections from LUA See Section 4.1 of the UWMP for tabulated retail water demand projections through 2040 and a description of the model methodology. 3.4 Proposed Project Water Demand Water demand estimates for the proposed project are detailed in a memo prepared by the SFPUC project team, provided in Attachment A. The proposed project is not encompassed in the San Francisco Planning Department s LUA 2012 projections as it does not result in population or employment growth. Therefore, the demand that would be generated by the proposed project is not encompassed within the San Francisco retail water demands that are presented in the 2015 UWMP. Water demand associated with the proposed project over the 20-year planning horizon is shown in the following table.

5 Memo to Commissioners WSA for Biosolids Digester Facilities Project February 16, 2017 Page 5 of 7 Table 2: Water Demand Based on Project Phasing Total Average Demand of Proposed Project (mgd) mgd = million gallons per day Notes: The demand shown in this table is the net increase in potable water demand (BDFP demand compared to existing solids processing facilities). Operation of the proposed project would begin as early as 2023 with the startup/commissioning period. 4.0 Conclusion 4.1 Comparison of Projected Supply and Demand Section 7.5 of the UWMP compares the SFPUC s retail water supplies and demands through 2040 during normal year, single dry-, and multiple dry-year periods. See Table 3, below, which is adapted from the UWMP (Table 7-4) with the addition of water demands attributed to the proposed project. Although water demands associated with the proposed project are not already captured in the retail demand projections presented in the UWMP, the demands are incremental and would not substantiate the need for additional supplies. With the addition of demands associated with the proposed project, total retail demand in 2035 is projected to be 86.1 mgd, which represents a 5.2 mgd, or 6 percent, increase over the 2035 demand projected in the 2010 UWMP. The ability to meet the demand of the retail customers is in large part due to development of 10 mgd of local WSIP supplies, including conservation, groundwater, and recycled water. These supplies are anticipated to be fully implemented over the next 10 to 15 years. Table 3 shows projected shortfalls of mgd resulting from the proposed project. In a normal year, single dry year, or multiple dry year 1, the SFPUC may draw up to 81 mgd from the RWS, thereby increasing the total retail supply beyond the volumes shown in Table 3 and eliminating the 0.2 mgd deficit. In years 2 and 3 of a multiple dry year event, the SFPUC may draw 79.5 mgd, which is already reflected the total retail supply shown in Table 3. The resulting deficit would be easily managed through voluntary conservation or rationing. If planned future water supply projects (i.e., San Francisco Groundwater Supply Project, Westside Recycled Water Project, Eastside Recycled Water Project, and onsite non-potable supplies) are not implemented, normal-year supplies may not be enough to meet projected retail demands. To balance any water supply deficits during normal years, the SFPUC may import additional water from the RWS beyond the retail allocation of 81 mgd, with mitigation implemented by the SFPUC and potential environmental surcharges if RWS deliveries exceed the 265 mgd interim supply limitation. If dry-year supply projects (i.e., Calaveras Dam Replacement Project, Lower Crystal Springs Dam Improvements Project, Alameda Creek Recapture, Regional Groundwater Storage and Recovery Project, and water transfers) are not implemented, existing dry year supplies may not be enough to meet projected retail demands. To balance any water supply deficits during dry years, the SFPUC may reduce system deliveries and impose customer rationing.

6 Memo to Commissioners WSA for Biosolids Digester Facilities Project February 16, 2017 Page 6 of 7 Table 3: Projected Supply and Demand Comparison with Proposed Project (mgd) Single Multiple Dry Years Normal Dry Year Year 1 Year 1 1 Year 2 2 Year 3 2 Total Retail Demand Excluding Proposed Project Demand of Proposed Project Total Retail Demand Including Proposed Project Total Retail Supply Surplus/(Deficit) Total Retail Demand Excluding Proposed Project Demand of Proposed Project Total Retail Demand Including Proposed Project Total Retail Supply Surplus/(Deficit) (0.2) (0.2) (0.2) (0.2) (0.2) Total Retail Demand Excluding Proposed Project Demand of Proposed Project Total Retail Demand Including Proposed Project Total Retail Supply Surplus/(Deficit) (0.2) (0.2) (0.2) (0.2) (0.2) Total Retail Demand Excluding Proposed Project Demand of Proposed Project Total Retail Demand Including Proposed Project Total Retail Supply Surplus/(Deficit) (0.2) (0.2) (0.2) (0.2) (0.2) Total Retail Demand Excluding Proposed Project Demand of Proposed Project Total Retail Demand Including Proposed Project Total Retail Supply Surplus/(Deficit) (0.2) (0.2) (0.2) (1.3) (1.3) Notes: 1. During a single dry year and multiple dry year 1, a system-wide shortage of 10% is in effect. Under the Water Shortage Allocation Plan (WSAP), the retail supply allocation at this stage of shortage is 36.0% of available RWS supply, or 85.9 mgd. However, due to the Phased WSIP Variant, only 81 mgd of RWS supply can be delivered. RWS supply is capped at this amount. 2. During multiple dry years 2 and 3, a system-wide shortage of 20% is in effect. Under the WSAP, the retail supply allocation at this stage of shortage is 37.5% of available RWS supply, or 79.5 mgd. RWS supply is capped at this amount. 3. Total retail demands correspond to those in Table 4-1 of the UWMP, and reflect both passive and active conservation, as well as water loss. 4. Total retail supplies correspond to those in Table 6-7 of the UWMP. Procedures for RWS allocations and the WSAP are described in Section 8.3 of the UWMP. Groundwater and recycled water are assumed to be used before RWS supplies to meet retail demand. However, if groundwater and recycled water supplies are not available, up to 81 mgd, or the corresponding capped amount in dry years, of RWS supply could be used.

7 Memo to Commissioners WSA for Biosolids Digester Facilities Project February 16, 2017 Page 7 of 7 The SFPUC remains committed to meeting the level of service goals and objectives outlined under WSIP. In addition, the SFPUC continues to explore other future supplies, including: Development of additional conservation and recycling. Development of additional groundwater supplies. Securing of additional water transfer volumes. Increasing Tuolumne River supply. 4.2 Findings Regarding the availability of water supplies to serve the proposed project beginning as early as 2023, the SFPUC finds, based on the entire record before it, as follows: During normal years, single dry years, and multiple dry years, the SFPUC has sufficient water supplies to serve the proposed project. With the addition of planned retail supplies, the SFPUC has sufficient water supplies available to serve its retail customers, including the demands of the proposed project, existing customers, and foreseeable future development. Approval of this WSA by the Commission is not equivalent to approval of the development project for which the WSA is prepared. A WSA is an informational document required to be prepared for use in the City s environmental review of a project under CEQA. It assesses the adequacy of water supplies to serve the proposed project and cumulative demand. Furthermore, this WSA is not a will serve letter and does not verify the adequacy of existing distribution system capacity to serve the proposed project. A will serve letter and/or hydraulic analysis must be requested separately from the SFPUC City Distribution Division to verify hydraulic capacity. If there are any questions or concerns, please contact Steve Ritchie at (415) or SRitchie@sfwater.org.

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9 Attachment A Biosolids Digester Facilities Project Demand Memo

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11 San Francisco Water Power Sewer Services of the San Francisco Public Utilities Commission 525 Golden Gate Avenue, 9th Floor San Francisco, CA F February 15, 2017 TO: FROM: RE: Fan Lau, Water Resources Specialist Carolyn Chiu, BDFP Project Manage Input to Water Supply Assessment for the Biosolids Digester Facilities Project This document provides information specified in the "Project Demand Memo for Preparation of WSA." Specifically, this document responds to the input requested for Items lb (Introduction) and 3b (Project Demand). Project Description (Item lb) The Biosolids Digester Facilities Project (the "project" or BDFP) would construct new solids treatment, odor control, energy recovery, and associated facilities at the San Francisco Public Utilities Commission's (SFPUC) Southeast Water Pollution Control Plant (SEP) in San Francisco. Most of the existing SEP solids treatment facilities (including the digesters) are over 60 years old, were not built to withstand the maximum credible earthquake, require significant maintenance, and are operating well beyond their useful life. Newer, more efficient treatment technologies have since been developed that produce a higher quality and reduced volume of biosolids, capture and treat odors more effectively, and maximize biogas production for heat and energy. The proposed BDFP would update and replace the aging SEP solids treatment system. Over the planning period for the BDFP (2045), projected increases in population will increase solids loads from about 187,000 pounds per day (2014) to about 280,000 pounds per day (2045) (SFPUC, 2016)1. The BDFP would be located on portions of the existing SEP property at 750 Phelps Street and 1700 Jerrold Avenue (Block and Lot 5262/009), and the adjacent properties at 1800 Jerrold Avenue (the Central Shops site, Block and Lot 5262/009) and 1801 Jerrold Avenue (the decommissioned Asphalt Plant site, Block and Lot 5281/001). The project site totals approximately 415,000 square feet. The project would involve the demolition of other onsite structures and installation of the following facilities: Solids Pretreatment Facility Thermal Hydrolysis Process (THS) Anaerobic Digestion THS Cooling Towers Biosolids Dewatering Facility Energy Recovery Facility Edwin M. Lee Mayor Francesca Vietor President Anson Moran Vice President Ann Moller Caen Commissioner Vince Courtney Commissioner Ike Kam Commissioner Harlan L. Kelly, Jr. General Manager I SFPUC. March.. Final Conceptual Engineer Report

12 WSA Input Memo for Biosolids Digester Facilities Project February 15, 2017 Page 2 of 4 Biogas Treatment Biogas Storage Waste Gas Burners Solids Odor Control Piping modifications and new pumps for existing pump stations Maintenance Shops Other ancillary facilities (electrical rooms, transformers, chemical storage, and diesel generator) The BDFP would require construction of new structures totaling less than 215,000 square feet (footprint). No new staff would be needed to operate new facilities. Currently, the SEP uses supplies from three water systems, as follows: No. 1 water (W1): potable water No. 2 water (W2): non-potable, disinfected and filtered SEP effluent No. 3 water (W3): non-potable, chlorinated SEP effluent The type of water used in the treatment system under the proposed project would depend on the process and required water quality. For example, W1, the highest quality water, would be used for the cooling tower and energy recovery facilities. W2 and W3 water would be used for wash water, chemical dissolution, dilution, and to maintain moisture for the odor control facilities. Project Demand (Item 3b) BDFP processes would increase overall water use. However, the BDFP has been designed to maximize use of SEP recycled water and/or other non-potable water, to the extent possible in its processes. Thus, the majority of the water needs (about 88 percent) would be supplied by the No. 2 and No. 3 water systems, while only about 12 percent would be associated with the No. 1 potable water system. Table 1 presents the existing and projected future water demand (process and non-process water [administration / maintenance only] and irrigation) for the proposed project, including for W1, W2, and W3. W2 and W3 demand are shown to demonstrate how SFPUC would minimize potable water use and reduce treated effluent that would otherwise be discharged into the Bay. As shown in Tables 1 and 2, the BDFP average demand for W1 is approximately 140 gallons per minute (gpm), or approximately 205,000 gallons per day (gpd). This would result in a net increase of approximately 162,000 gpd of potable water, above the 50,000 gpd that would trigger the preparation of a WSA. Nearly 100 percent of the W1 demand is associated with process needs. Irrigation water demand, which is currently met by potable water, is also assumed to be supplied by potable water under the proposed project due to the higher salinity levels of the existing SEP effluent. This may likely change when recycled water or other viable non-potable water source is identified. At this time however, with selection of the right palette of salt tolerant plants and

13 WSA Input Memo for Biosolids Digester Facilities Project February 15, 2017 Page 3 of 4 implementation of the appropriate irrigation strategies (e.g., avoid wetting leaves with recycled water, adjusting irrigation frequency to keep soils moist, leaching soils with gypsum periodically), existing recycled water that is currently produced at the SEP could likely be used. Other water sources may be available to meet the irrigation needs of the project, such as stormwater (captured during rainy events) 2 and greywater (captured from sinks). In addition, as discussed in the Final CER (SFPUC, 2016), landscape planting will reflect the strategies of the City s Water Efficient Irrigation Ordinance Requirements for Tier 2 projects and the Green Landscaping Ordinance, including consideration of irrigation with recycled water or harvested rain water, water-efficient/drought tolerant plantings, and automatic irrigation controllers equipped with climatological sensors. Project design has not proceeded to a level in which the plant palette has been selected, associated water requirements have been evaluated, or the specific water supplies have been identified for irrigation. Thus, the values specified in Table 2 are based on assumptions of the calculated landscape area, estimated water requirements of peak (71 gpm) irrigation, and hours of irrigation (6 hours) during the plant establishment period. Following the plant establishment period, it is expected that water demands would reduce to 10 gpm. By assuming the irrigation water needs would be supplied entirely by the use of potable water, the project is providing a conservative estimate of W1 use. As design progresses, the BDFP Team will determine the details to better gauge the water needs as well as investigate other alternatives to potable water that can be used for irrigation. Potable water, which is necessary for certain processes that require the lowest level of salinity, could be further reduced in the future. SFPUC has identified the Eastside Recycled Water Project as a potential project that would deliver disinfected tertiary level treated recycled water to a variety of customers on the east side of the City for non-drinking uses such as irrigation and toilet flushing. Title 22 disinfected tertiary level treated recycled water provides a variety of reuse opportunities, including supply for cooling or air conditioning, toilet and urinal flushing, and irrigation (e.g., in public spaces). If available, this level of recycled water could be used to meet proposed biosolids facilities water demand (process and non-process) as well as irrigation demand. Although not yet formally in the planning stage, the Eastside Recycled Water Project may be available by In compliance with the City s Reclaimed Water Use Ordinance, SFPUC proposes that all Irrigation pipelines would be single-piped with a crossover/air gap connection such that recycled water (Title 22) could be used if and when it becomes available in the future. In addition, bathrooms in BDFP buildings would be dual plumbed for recycled water use if and when it becomes available. 2 As discussed in the Final CER, the BDFP will comply with SFPUC s Stormwater Design Guidelines, and thus would be required to decrease runoff rate and volume using low-impact development (LID) or other green infrastructure approaches. Examples of LID measures that could be implemented include flow-through stormwater planters, and rain barrels / oversized downsprouts. The use of LID measures would offset potable water use (SFPUC, 2016). Since the publication of the Final CER, SFPUC replaced the SFPUC s Stormwater Design Guidelines with the San Francisco Stormwater Management Requirements (SMR) and Design Guidelines in The BDFP would be in compliance with the SMR.

14 WSA Input Memo for Biosolids Digester Facilities Project February 15, 2017 Page 4 of 4 The water demands provided in Tables 1 and 2 are for the horizon year The BDFP would be installed with the majority of the major facilities (e.g., all five proposed digesters) that would be needed during the horizon year. As such, water demand is not expected to change substantially between the start of operation (startup/commissioning period to begin as early as 2023) and the horizon year, and demand is not broken down by phases. In addition, water demand based on water year type is not provided as THP processes do not change depending on the hydrologic water type; thus a breakdown based on the hydrologic water type is also not provided.

15 Attachment A Table 1: Existing and Proposed Water Demand Facility Potable Water (W1) Non potable, Chlorinated and Filtered Water (W2) Non potable and Chlorinated Water (W3) Total (W1+W2+W3) Max (Peak Hour) Demand), gpm Avg Day Demand gpm Max (Peak Hour) Demand gpm Avg Day Demand gpm Max (Peak Hour) Demand, gpm Avg Day Demand gpm Max Demand gpm Avg Demand gpm (1) (2) (3) (4) (5) (6) (1)+(3)+(5) (2)+(4)+(6) Existing Overall SEP 1 (Liquid and Bisolids Facilities) ,550 3,000 6,450 3,320 Existing Biosolids Facilities 1,2, , , Project BDFP Facilities Process only ,070 1, ,574 1,888 Irrigation only 3, Non process 3, Total Projected BDFP Facilities demand Increase in Biosolids Facilities Avg demand (gpm) ,070 1, ,697 1, ,790 1,480 1, Increase in Biosolids Facilities Avg demand (gpd) 6 226, ,058 2,577,600 2,131,200 1,526, ,800 1,277,280 1,400,458 NOTES 1 Peak values from SFPUC, Final CER, March Average values from SFPUC, Draft Site Logistics Plan, March Values from Brown and Caldwell (December 2016). 4 It is assumed irrigation is intermittent and would be up to 71 gpm (or 7 gpm when a 10% diversity factor is applied for intermittent use). The irrigation demand is based on calculated landscape area, estimated water requirements of peak (71 gpm) irrigation, and hours of irrigation (6 hours) during the plant establishment period. Following the plant establishment period, it is expected that water demands would reduce to 10 gpm, but this is not reflected above in order to provide a conservative estimate.. 5 Based on an occupancy of 110 people/day. Note that there is no increase in staffing at SEP due to the project, these people will be existing staff at SEP who will move from one building to another. 6 SFPUC staff has clarified that secondary effluent demands (W2 and W3 system water) are nonpotable demands that would otherwise be discharged into the Bay if it were not reused for proposed operations. Thus, they're not included in the determination of whether a WSA is needed. Definitions: Max = maximum; Avg = average; gpm = gallons per minute; gpd = gallons per day; and NA = not applicable Input to the Water Supply Assessment 1 2/15/2017 For the BDFP

16 Table 2. SFPUC SEP BDFP No. 1 Water (W1) Demands Functional Area Average (gpd) Peak Hour (gpm) Average (mgd) Existing Demands Existing Biosolids Water Demands 43, New Biosolids Demands (2045) Biosolids process facilities (Cooling Tower and Boiler Makeup Water Feed) 198, Biosolids Irrigation a 5, Biosolids facilities fixtures (bathrooms, locker rooms) b Total new biosolids demands (2045) 205, Net W1 Demand Increase from BDFP Project 162, Source: Brown and Caldwell, December a. Based on calculated area and estimated water requirements, at 71 gpm (peak) irrigation would be accomplished in 6 hours during plant establishment. Estimates will be revisited during design. Following the plant establishment period, it is expected that water demands would reduce to 10 gpm. b. Based on an occupancy of 110 people/day. Definitions: gpd = gallons per day; gpm = gallons per minute; mgd = million gallons per day. Input to the Water Supply Assessment 2 2/15/2017 For the BDFP