DES MOINES (S&P Global Ratings) March 1, 2019--S&P Global Ratings revised its outlook to negative from stable and affirmed its 'AA' rating on Trinity River Authority (TRA), Tex.'s series 2018 contract revenue bonds, issued for its Walker-Calloway system. "The negative outlook revision reflects our view of the contract city's thin all-in debt service after incorporating administrative transfers, payment in lieu of taxes, franchise fee, and take-or-pay agreements in addition to supporting the general obligation (GO) debt at the contract city level in application of our criteria," said S&P Global Ratings credit analyst John Schulz. While neither city has any revenue bond debt outstanding, we view both as having extremely strong enterprise risk profiles and strong financial risk profiles in their