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Year Annual storage impact (TAF) -469 -263 +41 -206 -14 -159 -208 -192 Total SFPUC end-of- year storage (TAF) 1,048 785 826 620 606 447 239 47 Source: derived from data provided by the SFPUC; presentation by Yosemite Rivers Alliance, Table YRA-1. Editor's note — The current UWMP describes the Design Drought as an 8.5-year sequence (p. 92) and presents the resulting cutback percentages (Table 27, p. 117), but does not show the intermediate storage values. Disclosing the storage trajectory in an appendix lets Council and ratepayers see that physical supply is not exhausted until very late in the modeled sequence — a fact that is material to evaluating the >20% rationing scenario discussed in Edit 5. ────────────────────────────────────────────────────────────────────────────────────────── Edit 7 — Section 6, Climate Change / SFPUC Climate Studies (pp. 78–80) Subject: respond to Commissioner request for an LTVA-applicability discussion in the UWMP. The May 6 Item 4 staff report (p. 9) records that two Commissioners requested staff "take into consideration the Long- Term Vulnerability Assessment (LTVA) and Adaptation Plan for the SFPUC and be prepared to explain how this work applies to the UWMP." The current UWMP refers to the LTVA but does not explain its relationship to the Design Drought figures used elsewhere in the document. Recommended addition: Proposed insertion in the SFPUC Climate Change Studies subsection (Section 6): Relationship of the LTVA to the Design Drought used in this UWMP. The SFPUC's Long-Term Vulnerability Assessment, completed in partnership with the Water Research Foundation, evaluated regional water- supply reliability using 100 years of observed hydrologic data, 1,100 years of tree-ring–based reconstructions, and approximately 25,000 simulated stochastic model runs. None of the stochastic runs produced a drought sequence as severe as the SFPUC's Design Drought (described on p. 92). The Design Drought, rather than the LTVA's stochastic ensemble, is the planning input for the multiple-dry-year cutback percentages presented in Table 27 (p. 117) and for the SFPUC's Alternative Water Supply Program. This UWMP presents the SFPUC-derived Design Drought figures for regulatory completeness; the LTVA is included to give Council and ratepayers a fuller picture of the range of plausible future hydrologic conditions. Editor's note — This edit responds directly to the Commissioner request recorded on p. 9 of the staff report. It does not modify any SFPUC figure; it explains the relationship between two SFPUC products (the LTVA and the Design Drought) so that the UWMP itself answers the question Commissioners raised at the March 31 meeting.