S&P Global Ratings assigned its 'A-1+' rating to Tarrant Regional Water District, Texas' (TRWD) tax-exempt and taxable series A commercial paper (CP) program. Because it is an extendible maturity CP program with no revolving credit agreement or other liquidity support, the ratings are based on the long-term debt rating of 'AAA' on TRWD, which we are affirming. The outlook on the long-term rating is stable. The long-term rating reflects our assessment of the general creditworthiness of a deep pool of mainly municipal customers who purchase raw water-–in most cases on a full requirements basis--from TRWD. This includes contracts with: Fort Worth (60% of fiscal 2015 operating revenues), Arlington (17%), Trinity River Authority (TRA; 9.1%); and Mansfield (3.5%). A subordinate-lien net