Subpart A - General Provisions

§ 131.1 - Scope.

§ 131.2 - Purpose.

§ 131.3 - Definitions.

§ 131.4 - State authority.

§ 131.5 - EPA authority.

§ 131.6 - Minimum requirements for water quality standards submission.

§ 131.7 - Dispute resolution mechanism.

§ 131.8 - Requirements for Indian Tribes to administer a water quality standards program.

Subpart B - Establishment of Water Quality Standards

§ 131.10 - Designation of uses.

§ 131.11 - Criteria.

§ 131.12 - Antidegradation policy and implementation methods.

§ 131.13 - General policies.

§ 131.14 - Water quality standards variances.

§ 131.15 - Authorizing the use of schedules of compliance for water quality-based effluent limits in NPDES permits.

Subpart C - Procedures for Review and Revision of Water Quality Standards

§ 131.20 - State review and revision of water quality standards.

§ 131.21 - EPA review and approval of water quality standards.

§ 131.22 - EPA promulgation of water quality standards.

Subpart D - Federally Promulgated Water Quality Standards

§ 131.31 - Arizona.

§ 131.32 - [Reserved]

§ 131.33 - Idaho.

§ 131.34 - Kansas.

§ 131.35 - Colville Confederated Tribes Indian Reservation.

§ 131.36 - Toxics criteria for those states not complying with Clean Water Act section 303(c)(2)(B).

§ 131.37 - California.

§ 131.38 - Establishment of numeric criteria for priority toxic pollutants for the State of California.

§ 131.40 - Puerto Rico

§ 131.41 - Bacteriological criteria for those states not complying with Clean Water Act section 303(i)(1)(A).

§ 131.42 - Antidegradation Implementation Methods for the Commonwealth of Puerto Rico.

§ 131.43 - Maine.

§ 131.44 - Florida.

§ 131.45 - Revision of certain Federal water quality criteria applicable to Washington.

§ 131.46 - xxx

§ 131.47 - xxx