S&P Global Ratings lowered its short-term rating on San Francisco Public Utilities Commission's proposition E tax-exempt subseries A-2 and taxable subseries A-2-T commercial paper (CP) water notes to 'A-1' from 'A-1+'. The rating reflects our opinion of the credit and liquidity support Sumitomo Mitsui Banking Corp., acting through its New York branch, provides for the subseries A-2 and A-2-T CP notes in the form of an irrevocable direct-pay letter of credit (LOC). The LOC fully supports all CP note payment obligations. The previous rating reflects the commission's self-liquidity with a liquidity agreement provided by The Bank of Tokyo-Mitsubishi UFJ Ltd., acting through its New York Branch. We understand the structure is changing so the LOC will fully support the payments