...July 15, 2019 NEW YORK (S&P Global Ratings) July 15, 2019--S&P Global Ratings lowered its short-term rating on Houston Combined Utility System's series B-4 commercial paper (CP) notes to 'A-1' from 'A-1+'. The rating action reflects our assessment of the substitution of the current letter of credit (LOC) provided by State Street Bank & Trust Co. with a new LOC provided by PNC Bank N.A. We recognize there are currently no CP notes outstanding. The effective substitution date is July 12, 2019. The LOC will provide coverage for principal plus 270 days' interest at the maximum 10% rate. The issuing-and-paying agent has instructions to draw on the LOC on the dates and in the amounts necessary for principal-and-interest payments on all maturing CP. The issuing-and-paying agent has instructions not to issue notes with a maturity in excess of 270 days--the day preceding LOC expiration--or in amounts that would exceed the LOC commitment. The issuing-and-paying agent has further instructions to cease...