August 2013 EPA 820-F-13-027

1 of 13

Supplemental Information for 

Water Quality Standards Regulatory Clarifications Proposed Rule

NOTE: THE FOLLOWING REGULATORY TEXT IS A COMPARISON OF THE 

PROPOSED RULE LANGUAGE AND THE EXISTING RULE LANGUAGE. 

STRIKEOUTS INDICATE TEXT PROPOSED TO BE DELETED AND 

UNDERLINES INDICATE TEXT PROPOSED TO BE ADDED.

THE TEXT BELOW SHOWS ONLY THE PROVISIONS AFFECTED BY THE 

REVISIONS IN THE PROPOSED RULE. IT DOES NOT REPRESENT THE 

ENTIRETY OF THE PART 131 REGULATIONS.

For the reasons stated in the preamble, the EPA proposes to amend 40 CFR part 131 as 

follows:

PART 131—WATER QUALITY STANDARDS

1. The authority citation for part 131 continues to read as follows:

Authority: 33 U.S.C. 1251 et seq.

Subpart A-General Provisions

2. Amend § 131.2 by revising the first sentence to read as follows:

§ 131.2 Purpose.

A water quality standard defines the water quality goals of a water body, or portion 

thereof, by designating the use or uses to be made of the water and by setting criteria 

necessary that to protect the designated uses. * * *

3. Amend § 131.3 by revising paragraphs (h) and (j), and adding paragraph (m) to 

read as follows:

§ 131.3 Definitions.

* * * * *

(h) Water quality limited segment means any segment where it is known that water 

quality does not meet applicable water quality standards, and/or is not expected to meet 
August 2013 EPA 820-F-13-027

2 of 13

applicable water quality standards, even after the application of the technology-basesd

effluent limitations required by sections 301(b) and 306 of the Act.

* * * * *

(j) States include: The 50 States, the District of Columbia, Guam, the Commonwealth 

of Puerto Rico, Virgin Islands, American Samoa, the Trust Territory of the Pacific 

Islands, the Commonwealth of the Northern Mariana Islands, and Indian Tribes that EPA 

determines to be eligible for purposes of the water quality standards program.

* * * * *

(m) Highest attainable use is the aquatic life, wildlife, and/or recreation use that is 

both closest to the uses specified in section 101(a)(2) of the Act and attainable, as 

determined using best available data and information through a use attainability analysis 

defined in § 131.3(g). 

4. Amend § 131.5 by:

a. Revising paragraphs (a)(1) and (a)(2);

b. Redesignating paragraphs (a)(3) through (a)(5) as (a)(4) through (a)(6) and adding a 

new paragraph (a)(3); and

c. Revising paragraph (b).

The revisions and additions read as follows:

§ 131.5 EPA authority.

(a) * * *

(1) Whether the State has adopted designated water uses which are consistent with the 

requirements of the Clean Water Act;
August 2013 EPA 820-F-13-027

3 of 13

(2) Whether the State has adopted criteria that protect the designated water uses based 

on sound scientific rationale;

(3) Whether the State has adopted an antidegradation policy consistent with § 

131.12(a), and if the State has chosen to adopt implementation methods, whether those 

implementation methods are consistent with § 131.12;

* * * * *

(b) If EPA determines that the State's or Tribe's water quality standards are consistent 

with the factors listed in paragraphs (a)(1) through (a)( 56) of this section, EPA approves 

the standards. EPA must disapprove the State's or Tribe's water quality standards and 

promulgate Federal standards under section 303(c)(4), and for Great Lakes States or 

Great Lakes Tribes under section 118(c)(2)(C) of the Act, if State or Tribal adopted 

standards are not consistent with the factors listed in paragraphs (a)(1) through (a)( 56) of 

this section. EPA may also promulgate a new or revised standard when necessary to meet 

the requirements of the Act.

* * * * *

Subpart B—Establishment of Water Quality Standards

5. Amend § 131.10 by revising paragraphs (g) introductory text and paragraphs, (j), 

and (k) to read as follows:

§ 131.10 Designation of uses.

* * * * *

(g) Pursuant to § 131.10(j), States may designate or remove a designated use or a subcategory of a use as long as the action does which is not remove protection for an existing 

use, as defined in §131.3, or establish sub-categories of a use if, and the State can 
August 2013 EPA 820-F-13-027

4 of 13

demonstrate that attaining the use is not feasible because: of one of the six factors in this 

paragraph. If a State adopts new or revised water quality standards based on a use 

attainability analysis, the State shall also adopt the highest attainable use and the criteria 

to protect that use. To meet this requirement, States may, at their discretion, utilize their 

current use categories or subcategories, develop new use categories or subcategories, or 

adopt another use which may include a location-specific use.

* * * * *

(j) A State must conduct a use attainability analysis as described in § 131.3(g), and § 

131.10(g), whenever:

(1) The State designates or has designated uses for a water body for the first time that 

do not include the uses specified in section 101(a)(2) of the Act, or 

(2) The State wishes to remove a designated use that is specified in section 101(a)(2) 

of the Act, to remove a sub-category of such a use, or to adopt designate a subcategoriesy of such a uses specified in section 101(a)(2) of the Act which requires criteria

less stringent criteria than previously applicable.

(k) A State is not required to conduct a use attainability analysis under this regulation 

whenever designating uses which include those specified in section 101(a)(2) of the Act:

(1) The State designates or has designated uses for a water body for the first time that 

include the uses specified in section 101(a)(2) of the Act, or 

(2) The State wishes to remove a designated use that is not specified in section 

101(a)(2) of the Act, or designate a sub-category of a use specified in section 101(a)(2) of 

the Act which requires criteria at least as stringent as previously applicable.
August 2013 EPA 820-F-13-027

5 of 13

6. Amend § 131.11 by revising paragraphs (a)(2) and (b) introductory text to read as 

follows:

A. § 131.11-Criteria.

(a) * * *

(2)Toxic Pollutants. States must review water quality data and information on 

discharges to identify specific water bodies where toxic pollutants may be adversely 

affecting water quality or the attainment of the designated water use or where the levels 

of toxic pollutants are at a level to warrant concern and must adopt criteria for such toxic 

pollutants applicable to the water body sufficient to protect the designated use. Where a 

State adopts narrative criteria for toxic pollutants to protect designated uses, the State 

must provide information identifying the method by which the State intends to regulate 

point source discharges of toxic pollutants on water quality limited segments based on 

such narrative criteria. Such information may be included as part of the standards or may 

be included in documents generated by the State in response to the Water Quality 

Planning and Management Regulations (40 CFR part 35130).

(b) Form of criteria:Form of criteria: In establishing criteria, States should:

* * * * *

7. Amend § 131.12 by revising the section heading and paragraphs (a) introductory 

text and (a)(2), and adding paragraph (b) to read as follows:

§ 131.12 Antidegradation Policy and Implementation Methods.

(a) The State shall develop and adopt a statewide antidegradation policy and identify 

the methods for implementing such policy pursuant to this subpart. The antidegradation 
August 2013 EPA 820-F-13-027

6 of 13

policy and implementation methods shall, at a minimum, be consistent with the 

following:

* * * * *

(2) Where the quality of the waters exceed levels necessary to support the protection 

and propagation of fish, shellfish, and wildlife and recreation in and on the water, that 

quality shall be maintained and protected unless the State finds, after full satisfaction of 

the intergovernmental coordination and public participation provisions of the State’s 

continuing planning process, that allowing lower water quality is necessary to 

accommodate important economic or social development in the area in which the waters 

are located. In allowing such degradation or lower water quality, the State shall assure

ensure water quality adequate to protect existing uses fully. Further, the state shall assure

ensure that there shall be achieved the highest statutory and regulatory requirements for 

all new and existing point sources and all cost-effective and reasonable best management 

practices for nonpoint source control.

* * * * *

(b) The State shall develop and make available to the public statewide methods for 

implementing the antidegradation policy adopted pursuant to paragraph (a) of this 

section. A State’s antidegradation implementation methods shall be designed to achieve 

antidegradation protection consistent with paragraph (a) of this section. Such methods 

must ensure that:

(1) High quality waters are identified on a parameter-by-parameter basis or on a water 

body-by-water body basis at the State’s discretion, but must not exclude any water body 
August 2013 EPA 820-F-13-027

7 of 13

from high quality water protection solely because not all of the uses specified in CWA 

section 101(a)(2) are attained; and

(2) The State will only make a finding that lowering high water quality is necessary, 

pursuant to paragraph (a)(2) of this section, after conducting an alternatives analysis that 

evaluates a range of non-degrading and minimally degrading practicable alternatives that 

have the potential to prevent or minimize the degradation associated with the proposed 

activity. If the State can identify any practicable alternatives, the State must choose one 

of those alternatives to implement when authorizing a lowering of high water quality.

8. Add § 131.14 to subpart B to read as follows:

§ 131.14 Water quality standards variances.

States may, at their discretion, grant variances subject to the provisions of this section 

and public participation requirements at § 131.20(b). A water quality standards variance 

(WQS variance) is a time-limited designated use and criterion for a specified pollutant(s), 

permittee(s), and/or water body or waterbody segment(s) that reflect the highest 

attainable condition during the specified time period. WQS variances are water quality 

standards subject to EPA review and approval or disapproval and must be consistent with 

this section. Any such WQS variances adopted after [effective date of the final rule] must 

be consistent with this regulatory section.

(a) Applicability:

(1) All applicable WQS not specifically addressed by the WQS variance 

remain applicable. 

(2) (i) Where a state adopts a WQS variance, the State regulations must 

continue to reflect the underlying designated use and criterion unless the 
August 2013 EPA 820-F-13-027

8 of 13

State adopts and EPA approves a revision to the underlying designated use 

and criterion consistent with § 131.10 or § 131.11. 

(ii) The interim requirements specified in the WQS variance are in effect 

during the term of the WQS variance and apply for CWA section 402 

permitting purposes and in issuing certifications under section 401 of the 

Act for the permittee(s), pollutant(s), and/or water body or waterbody 

segment(s) covered by the WQS variance. For these limited purposes, the 

interim requirements will be the standards applicable for purposes of the 

CWA under 40 CFR 131.21(c)-(e).

(3) A WQS variance shall not be granted if the designated use and criterion 

addressed by the proposed WQS variance can be achieved by 

implementing technology-based effluent limits required under sections 

301(b) and 306 of the Act.

(b) Submission Requirements:

(1) A WQS variance must specify the following:

(i) Identifying information: A WQS variance must identify the 

pollutant(s), permittee(s), and/or the water body or waterbody 

segment(s) to which the WQS variance applies.

(ii) WQS that apply during a variance for CWA section 402 

permitting purposes and in issuing certifications under section 

401 of the Act: A WQS variance must specify:

(A) The highest attainable interim use and interim numeric 

criterion, or 
August 2013 EPA 820-F-13-027

9 of 13

(B) An interim numeric effluent condition that reflects the 

highest attainable condition for a specific permittee(s) during the 

term of the variance. Neither (A) nor (B) of this paragraph shall 

result in any lowering of the currently attained water quality 

unless a time-limited lowering of water quality is necessary 

during the term of a variance for restoration activities, consistent 

with paragraph (b)(2)(ii) of this section.

(iii) Date the WQS variance will expire: States must include an 

expiration date for all WQS variances, consistent with paragraph 

(b)(2) of this section. WQS variances must be as short as 

possible but expire no later than 10 years after state adoption. 

(2) The State must submit a demonstration justifying the need for a WQS 

variance. For a WQS variance to a use specified in section 101(a)(2) of the 

Act or a sub-category of such a use, the State must submit a 

demonstration that attaining the designated use and criterion is not feasible 

during the term of the WQS variance because:

(i) One of the factors listed in § 131.10(g) applies, or 

(ii) Actions necessary to facilitate restoration through dam removal

or other significant wetland or stream reconfiguration activities 

preclude attainment of the designated use and criterion while the 

actions are being implemented.

(3) For a waterbody variance, the state must identify and document any costeffective and reasonable best management practices for nonpoint source 
August 2013 EPA 820-F-13-027

10 of 13

controls related to the pollutant(s) and location(s) specified in the WQS 

variance that could be implemented to make progress towards attaining the 

designated use and criterion. A State must provide public notice and 

comment for any such documentation. 

(c) Implementing variances in NPDES permits: Consistent with paragraph (a)(2)(ii) 

of this section, a WQS variance serves as the basis of a water quality-based 

effluent limit included in a NPDES permit for the period the variance is in effect. 

Any limitations required to implement the WQS variance shall be included as 

conditions of the NPDES permit for the permittee(s) subject to the WQS variance. 

(d) WQS variance renewals: EPA may approve a WQS variance renewal if the State 

meets the requirements of this section and provides documentation of the actions

taken to meet the requirements of the previous WQS variance. For a waterbody 

WQS variance renewal, the state must also provide documentation of whether and 

to what extent BMPs have been implemented to address the pollutant(s) subject to 

the WQS variance and the water quality progress achieved during the WQS 

variance period. Renewal of a WQS variance may be disapproved if the applicant 

did not comply with the conditions of the original WQS variance, or otherwise 

does not meet the requirements of this section.

9. Add § 131.15 to subpart B to read as follows:

§ 131.15 Compliance schedule authorizing provisions.

A State may, at its discretion and consistent with state law, authorize schedules of 

compliance for water quality-based effluent limits (WQBELs) in NPDES permits by 

including a compliance schedule authorizing provision in its water quality standards or 
August 2013 EPA 820-F-13-027

11 of 13

implementing regulations. Any such provision is a water quality standard subject to EPA 

review and approval and must be consistent with sections 502(17) and 301(b)(1)(C) of 

the Act. Individual compliance schedules issued pursuant to such authorizing provisions 

are not themselves water quality standards. Individual compliance schedules must be 

consistent with CWA section 502(17), the state’s EPA-approved compliance schedule 

authorizing provision, and the requirements of §§ 122.2 and 122.47.

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

10. Amend § 131.20 by revising paragraphs (a) and (b) to read as follows:

§ 131.20State review and revision of water quality standards.

(a) State Review. The State shall from time to time, but at least once every 3 years, 

hold public hearings for the purpose of reviewing applicable water quality standards and, 

as appropriate, modifying and adopting standards; in particular, . Aany water body 

segment with water quality standards that do not include the uses specified in section 

101(a)(2) of the Act shall be re-examined every 3 years to determine if any new 

information has become available. If such new information indicates that the uses 

specified in section 101(a)(2) of the Act are attainable, the State shall revise its standards 

accordingly. Similarly, a State shall re-examine its water quality criteria to determine if 

any criteria should be revised in light of any new or updated CWA section 304(a) criteria 

recommendations to assure that designated uses continue to be protected. Procedures 

States establish for identifying and reviewing water bodies for review should be 

incorporated into their Continuing Planning Process.

(b) Public Participation. The State shall hold a public hearings for the purpose of 

reviewing or revising water quality standards, in accordance with provisions of State law, 
August 2013 EPA 820-F-13-027

12 of 13

EPA’s water quality management regulation (40 CFR 130.3(b)(6)) and EPA’s public 

participation regulation (40 CFR part 25). The proposed water quality standards revision 

and supporting analyses shall be made available to the public prior to the hearing.

* * * * *

11. Amend § 131.22 by revising paragraph (b) to read as follows:

§ 131.22 EPA promulgation of water quality standards.

* * * * *

(b) The Administrator may also propose and promulgate a regulation, applicable to 

one or more States, setting forth a new or revised standard upon determining such a 

standard is necessary to meet the requirements of the Act. To constitute an 

Administrator’s determination, such determination must:

(1) Be signed by the Administrator or his or her duly authorized delegate, and 

(2) Contain a statement that the document constitutes an Administrator’s 

determination under section 303(c)(4)(B) of the Act.

* * * * *

C. Subpart D-Federally Promulgated Water Quality Standards

12. Amend § 131.34 by revising paragraph (c) to read as follows:

§ 131.34 Kansas.

* * * * *

(c) Water quality standard variances. The Regional Administrator, EPA Region 7, is 

authorized to grant variances from the water quality standards in paragraphs (a) and (b) of 

this section where the requirements of this paragraph (c) §131.14 are met. 

13. Amend § 131.40 by revising paragraph (c) to read as follows: 
August 2013 EPA 820-F-13-027

13 of 13

§ 131.40 Puerto Rico.

* * * * *

(c) Water quality standard variances. The Regional Administrator, EPA Region 2, is 

authorized to grant variances from the water quality standards in paragraphs (a) and (b) of 

this section where the requirements of this paragraph (c) §131.14 are met.