[Code of Federal Regulations] [Title 40, Volume 18] [Revised as of July 1, 2002] From the U.S. Government Printing Office via GPO Access [CITE: 40CFR130.26] [Page 360] TITLE 40--PROTECTION OF ENVIRONMENT CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PART 130--WATER QUALITY PLANNING AND MANAGEMENT--Table of Contents Subpart C--Identifying Impaired Waterbodies And Establishing Total Maximum Daily Loads (TMDLs) Sec. 130.26 How do you apply your water quality standards antidegradation policy to the listing of impaired waterbodies? (a) Water quality standards as defined at 40 CFR part 131 include several requirements, including one for a State antidegradation policy. Your list must include waterbodies consistent with your antidegradation policy as described below. (1) Any waterbody is impaired if it is not maintaining a designated use or more protective existing use that was attained on or after November 28, 1975. (2) Any Tier 3 waterbody is impaired when the level of water quality that existed at the time the waterbody was designated as Tier 3 has declined. Tier 3 waters are waters you have designated as outstanding national resource waters. (b) [Reserved]