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Water: Reference Library

Policy & Guidance: Reference Library

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This page contains an index of EPA documents related to water quality standards, including those referenced in the WQS Handbook. You can sort the index alphabetically, by publication date, or by topic.

Please visit our Water Quality Standards Handbook for comprehensive guidance on the Water Quality Standards Program and to provide context for the documents below.

Please visit our regulations and determinations page to find a specific water quality standards regulation, determination, proposed or promulgated standard, or withdrawal notice published in the federal register.

Click on the up or down arrow in each column heading below to sort the table by that column in ascending or descending order.

Topic Title Publication Date EPA Number
(if assigned)
Antidegradation Tier 2 Antidegradation Reviews and Significance Thresholds, Memorandum from Ephraim King (PDF) (4 pp, 169K) 2005/08/10
Antidegradation Antidegradation Policy Approvals and Endangered Species Act Consultations, Memorandum from Geoffrey Grubbs  (PDF) (7 pp, 280K) 2005/01/27
Antidegradation Interpretation of Federal Antidegradation Regulatory Requirement, Memorandum from Tudor Davies (PDF) (449K) 1994/02/22
Antidegradation Antidegradation Policy, Memorandum from William Diamond (PDF) (55K) 1991/06/13
Antidegradation Application of Antidegradation Policy to the Niagara River, Memorandum from Margaret Prothro (PDF) (144K) 1989/08/04
Antidegradation EPA Designation of Outstanding National Resource Waters, Memorandum from William Diamond (PDF) (409K) 1989/05/25
Antidegradation Antidegradation Policy, Memorandum from Margaret Prothro (PDF) (293K) 1985/12/10
Antidegradation Antidegradation Policy, Memorandum from Patrick Tobin (PDF) (80K) 1985/11/22
Antidegradation Questions and Answers on Antidegradation (PDF) (15 pp, 1MB) 1985/08
Antidegradation Compendium of Department of the Interior Statements on Non-Degradation of Interstate Waters (PDF) (58 pp, 3.4MB) 1968/08/01
Antidegradation Antidegradation, Wasteloads, and Permits, Memorandum from Edwin Johnson (PDF) (77K) 1988/01/01
Arsenic Arsenic Decision, Memorandum from Robert Perciasepe (PDF) (3 pp, 334K) 1995/02/06
Assessment Thesaurus of Terms Used in Microbiological Risk Assessment 2007/07/01
Assessment Consolidated Assessment and Listing Methodology: Toward a Compendium of Best Practices 2002/07/01
Assessment Biological Methods Manual (Biological Field and Laboratory Methods for Measuring the Quality of Surface Waters and Effluents) (PDF) (194 pp, 8.3MB) 1973/07/01 670-4-73-001
Assessment, Biological A Primer on Using Biological Assessments to Support Water Quality Management (PDF) (108 pp, 6.1MB) 2011/10/01 810-R-11-01
Assessment, chronic toxicity Short-Term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms 2002/10/01 821-R-02-013
Assessment, chronic toxicity Short-Term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Marine and Estuarine Organisms 2002/10/01 821-R-02-014
Assessment, toxicity Methods for Measuring Acute Toxicity of Effluents to Freshwater and Marine Organism 2002/10/01 821-R-02-012
Bacteria criteria Ambient Water Quality Criteria for Bacteria (PDF) (662K) 1986/01/01 440/5-84-002
Biological criteria Biological Assessments: Key Terms and Concepts (PDF) (2 pp, 1.6MB) 2011/03/01 820-F-11/006
Biological criteria Summary of Biological Assessment Programs and Biocriteria Development for States, Tribes, Territories, and Interstate Commissions: Streams and Wadeable Rivers 2002/12/01 822-R-02-048
Biological criteria Using Biological Data as Indicators of Water Quality (PDF) (38 pp, 237K) 2002/07/01
Biological criteria Stressor Identification Guidance Document  2000/12/01 822-B-00-005
Biological criteria Summary of State Biological Assessment Programs for Streams and Rivers (PDF) (168 pp, 6.7MB) 1996/02/01 230-R-96-007
Biological criteria Policy on Biological Assessments and Criteria (PDF) (19 pp, 2.3MB) 1991/06/19
Biological criteria Application of Clean Water Act Section 401 State Water Quality Certification to Federal Energy Regulatory Commission (FERC) Licenses, Letter to the Honorable Lois Cashell, Secretary, Federal Energy Regulatory Commission (PDF) (4 pp, 443K) 1991/01/18
Biological criteria Biological Criteria: National Program Guidance for Surface Waters (PDF) (68 pp, 5MB) 1990/04/01 440/5-90-004
Biological criteria Biological Assessments and Criteria: Crucial Components of Water Quality Programs (PDF) (6 pp, 1.1MB) 2002/01/01 822-F-02-006
Biological criteria Lake and Reservoir Bioassessment and Biocriteria: Technical Guidance Document 1998/01/01 841-B-98-007
Chesapeake Bay Response to Petition from Chesapeake Bay Foundation 2005/06/13
Conditional Approvals Guidance for the Use of Conditional Approvals for State Water Quality Standards, Memorandum from Margaret Prothro (PDF) (4 pp, 639K) 1989/06/20
Copper criteria Streamlined Water-Effect Ratio Procedure for Discharges of Copper (PDF) (41 pp, 117K) 2001/03/01 822-R-01-005
Criteria Guidance Document on Expression of Aquatic Life Criteria as Dissolved Criteria (PDF) (30 pp, 1.4MB) 1993/10/01
Criteria Guidance on the Use of Criteria Contained in "Quality Criteria For Water" During the Review of State Water Quality Standards Revisions (PDF) (124K) 1978/01/16
Criteria National Recommended Water Quality Criteria Current
Criteria List of EPA Water Quality Criteria Documents 
Criteria Guidelines for Deriving Numerical National Water Quality Criteria for the Protection of Aquatic Organisms and Their Uses (PDF) (59 pp, 556K) 1985/01/01 PB85-227049
Designated Uses Designating Attainable Uses Symposium, 2002 2002/06/03
Designated Uses-Recreation Designation of Recreation Uses (PDF) (6 pp, 503K) 1989/09/07
Dissolved oxygen criteria Aquatic Life Criteria for Dissolved Oxygen (Saltwater) Cape Cod to Cape Hatteras 2000/11/01 822-R-00-012
Downstream Response to Sierra Club Petition 2004/06/25
Downstream Favorable Supreme Court Decision Concerning Interstate Water Pollution, Memorandum from Raymond Ludwiszewski (Arkansas v. Oklahoma) (PDF) (29 pp, 2MB) 1992/02/27
Downstream Templates for Narrative Downstream Protection Criteria in State Water Quality Standards 2014/02/14 820-F-14-002
Downstream Protection of Downstream Waters in Water Quality Standards: Frequently Asked Questions (PDF) (12 pp, 614K)
2014/6 820-F-14-001
Downstream Protection of Downstream Waters in Water Quality Standards: Frequently Asked Questions   2014/7 820-F-14-001
Downstream Decision Tree Tool for Downstream Protection 2014/11/17
Economic Interim Economic Guidance for Water Quality Standards: Workbook 1995/03/01 823/B-95-002
Effluent Dependent Ecosystems Region 9 Guidance for Modifying Water Quality Standards and Protecting Effluent-Dependent Ecosystems —Interim Final (PDF) (26 pp, 164K) 1992/06/17
Emerging contaminants Aquatic Life: Contaminants of Emerging Concern White Paper 2008/06/03
Endangered Species Act Consultation Memorandum of Agreement Between the Environmental Protection Agency, Fish and Wildlife Service, and National Marine Fisheries Service Regarding Enhanced Coordination Under the Clean Water Act and the Endangered Species Act; Notice 2001/02/22 823-F-01-002
Endangered Species Act Consultation Endangered Species Consultation Handbook (PDF) (315 pp, 919K) 1998/03/01
Endangered Species Act Consultation Endangered Species Act Joint Guidance (PDF) (14 pp, 781K) 1992/07/27
Existing Uses Questions and Answers on EPA's Existing Use Policy, Letter to Mr. Derek Smithee, State of Oklahoma Water Resources Board (PDF) (12 pp, 3.8MB) 2008/09/05
Existing Uses Determination of "Existing Uses" for Purposes of Water Quality Standards Implementation, Memorandum from Patrick Tobin (PDF) (157K) 1986/04/07
Existing Uses Interpretation of the Term "Existing Uses" Under the Antidegradation Policy (PDF) (54K) 1985/02/21
Fish and Shellfish Advisories Guidance: Use of Fish and Shellfish Advisories and Classifications in 303(d) and 305(b) Listing Decisions, Letter from Geoffrey Grubbs and Robert Wayland (PDF) (68K) 2000/10/24
Fish consumption Estimated per capita fish consumption in the United States (PDF) (262 pp, 3.2MB) 2002/08/01 821-C-02-003
Fish consumption National Guidance for Assessing Chemical Contaminant Data for Use in Fish Advisories 1996-2002 823-B-00-007, 823-B-00-008, 823-B-00-009, 823R95001
Great Lakes Acceptable Risk Levels in Great Lakes Waters, Fact Sheet 2006/08/01 823-F-06-012
Great Lakes Water Quality Guidance for the Great Lakes System: Supplementary Information Document (SID) (PDF) (774 pp, 1.2MB) 1995/03/01 820-B-95-001
Groundwater Water Quality Standards and Underground Waters, Memorandum from Joan Bernstein (PDF) (4 pp, 424K) 1979/05/29
Human health criteria Methodology for Deriving Ambient Water Quality Criteria for the Protection of Human Health 2000/10/01 822-B-00-004
Implementation Plans Revision of Water Quality Standards and Implementation Plans Under [Section] 303 of the Federal Water Pollution Control Act, Memorandum from William Frick (PDF) (8 pp, 498K) 1975/02/03
Interstate Waters National Stream Use Policy, Memorandum to Acting Director, Water Planning Division (PDF) (18K) 1972/10/15
Marinas Section 401 Certification of Marinas, Memorandum from Catherine Winer (PDF) (5 pp, 505K) 1985/11/12
Marine pH criteria Marine pH Criteria, Letter to Center for Biological Diversity (PDF) (4 pp, 246K) 2010/04/15
Metals criteria Modifications to "Interim Guidance on Determination and Use of Water-Effect ratios for Metals" and EPA’s "Recalculation Procedure when Deriving Site-Specific Criteria" (PDF) (21 pp, 187K) 1997/12/03
Metals criteria Interim Guidance on Determination and Use of Water-Effect ratios for Metals, Memorandum from Tudor Davies (PDF) (134 pp, 8.2MB) 1994/02/22 823/B-94-001
Metals criteria Office of Water Policy and Technical Guidance on Interpretation and Implementation of Aquatic Life Metals Criteria (PDF) (49 pp, 2.5MB) 1993/10/01 822/F-93-009
Mixing Zones Initial Zones of Dilution for Bacteria in Rivers and Streams, Memorandum from Ephraim King (PDF) (3 pp, 655K) 2008/11/12
Mixing Zones Compilation of EPA Mixing Zone Documents 2006/07/01 823-R-06-003
Mixing Zones EPA Guidance on Application of State Mixing Zone Policies in EPA-issued NPDES Permits, Memorandum from Robert Perciasepe (PDF) (471K) 1996/08/06
Mixing Zones Mixing Zones for Water Quality Standards, Memorandum from Richard Stoll (PDF) (2 pp, 265K) 1979/05/01
Mixing Zones Decision no. 31 of the General Counsel on Matters of Law Pursuant to 40 CFR Section 125.36(m) (PDF) (5 pp, 167K) 1975/10/14
Mixing Zones Mixing Zones, Memorandum from Robert Zenner (PDF) (3 pp, 345K) 1973/10/02
Modeling Guidance Document on Dynamic Modeling and Translators (PDF) (30 pp, 1.4MB) see page 18 1993/08/01
Monitoring Guidance Document on Monitoring (PDF) (30 pp, 1.4MB) see page 29 1993/10/01
Monitoring State Water Monitoring and Waste Load Allocation (PDF) (52 pp, 3.3MB) 1985/10/01 440/4-85-031
Narrative translator criteria Option 3 of Section 303(c)(2)(B) Guidance, Memorandum from David Sabock (PDF) (2 pp, 275K) 1990/01/03
Natural Conditions Framework A Framework for Defining and Documenting Natural Conditions for Development of Site-Specific Natural Background Aquatic Life Criteria for Temperature, Dissolved Oxygen, and PH: Interim Document (PDF)  (28 pp, 542K) 2015/02/12 820-R-15-001
Nonpoint Sources Nonpoint Source Guidance 1996/05/01
Nonpoint Sources Nonpoint Source Guidance 1996/05/01
Nonpoint Sources Guidance Specifying Management Measures for Sources of Nonpoint Pollution in Coastal Waters


Nonpoint sources Nonpoint Source Controls and Water Quality Standards, Memorandum from Carl Myers (PDF) (9 pp, 835K) 1987/08/19 FY-87-49
Nonpoint Sources Answers to Questions on Nonpoint Sources and WQS, Memorandum from Lawrence Jensen (PDF) (69K) 1986/03/07
Nonpoint Sources Coastal Nonpoint Pollution Control Program: Program Development and Approval Guidance (PDF) (68 pp, 654K) 1993/01/01 841B93003
Nutrients Bioconfirmation, Letter to Maine Department of Environmental Protection (PDF) (4 pp, 754K) 2011/12/22
Nutrients Response letter to the Mississippi River Petition, July 29, 2011 (PDF) (7 pp, 1.6MB) 2011/07/29
Nutrients Technical Assistance for Developing Nutrient Site-Specific Alternative Criteria in Florida, Interim Draft (PDF) (45 pp, 883K) 2011/06/01
Nutrients Working in Partnership with States to Address Phosphorus and Nitrogen Pollution through Use of a Framework for State Nutrient Reductions, Memorandum from Nancy Stoner, (a.k.a. Framework Memo) (PDF) (6 pp, 401K) 2011/03/16
Nutrients Letter to New England Interstate Water Pollution Control Commission, March 1, 2011 (PDF) (4 pp, 815K) 2011/03/01
Nutrients EPA Response to the Maine Congressional Delegation’s January 21, 2011 Letter (PDF) (9 pp, 854K) 2011/02/15
Nutrients Using Stressor-response Relationships to Derive Numeric Nutrient Criteria Technical Guidance (PDF) (93 pp, 1.9MB) 2010/11/01 820-S-10-001
Nutrients An Urgent Call to Action: Report of the State-EPA Nutrient Innovations Task Group (PDF) (170 pp, 5.6MB) 2009/08/27
Nutrients EPA Needs to Accelerate Adoption of Numeric Nutrient Water Quality Standards, OIG Report 09-P-0223 (PDF) (23 pp, 319K) 2009/08/26 09-P-0223
Nutrients State Adoption of Numeric Nutrient Standards 1998–2008 Status Report 2008/12/01 821-F-08-007
Nutrients Nutrient Criteria Technical Guidance: Wetlands 2008/06/01 822-B-08-001
Nutrients Nutrient Pollution and Numeric Water Quality Standards, Memorandum from Ben Grumbles 2007/05/25
Nutrients Establishing numeric nutrient criteria, Letter from Ben Grumbles to the Natural Resources Defense Council (PDF) (5 pp, 1MB) 2004/03/04
Nutrients Development and Adoption of Nutrient Criteria into Water Quality Standards, Memorandum from Geoffrey Grubbs (PDF) (21 pp, 246K) 2001/11/14
Nutrients Nutrient Criteria Technical Guidance Manual: Estuarine and Coastal Marine Waters 2001/10/01 822-B-01-003
Nutrients Nutrient Criteria Technical Guidance: Rivers and Streams 2000/07/07 822-B-00-002
Nutrients Nutrient Criteria Technical Guidance: Lakes and Reservoirs 2000/07/07 822-B-00-001
Nutrients National Strategy for the Development of Regional Nutrient Criteria (PDF) (53 pp, 271K) 1998/06/01 822-R-98-002
Ocean Acidification Integrated Reporting and Listing Decisions Related to Ocean Acidification, Memorandum from Denise Keehner 2010/11/15
Recreational Criteria Recreational Water Quality Criteria (draft) (PDF) (73 pp, 543K) 2011/12/09 820-D-11-002
Recreational Criteria Summary of Stakeholder Meeting on EPA’s Development of New or Revised Recreational Water Quality Criteria June 14–15, 2011 – New Orleans, Louisiana (PDF) (7 pp, 133K) 2011/06/14
Recreational Criteria Recreational Water Criteria – Critical Path Science Plan 2007/08/31 823-R-08-002
Recreational Criteria Bacteria Rule for Coastal and Great Lakes Recreation Waters (BEACH Act rule) 2004/11/16
Recreational Criteria Beaches Environmental Assessment and Coastal Health Act of 2000 2000/01/24 PUBLIC LAW 106–284
Reporting Watershed Monitoring and Reporting Requirements for Section 319 National Monitoring Program Projects 1991/08/30 843B91113
Reporting Integrated Reporting (IR) Guidelines under Sections 303(d), 305(b), and 314 of the Clean Water Act
Seaward Extent of State WQS Seaward Extent of State Water Quality Standards, Memorandum from Cathy Winer (PDF) (4 pp, 185K) 1985/10/31
Sediment Promoting Water, Superfund and Enforcement Collaboration on Contaminated Sediments (PDF) (3 pp, 1MB) 2015/02/12
Sediment Contaminated Sediment Management Strategy (PDF) (131 pp, 679K) 1998/04/01 823-R-98-001
Sediment criteria Suspended and Bedded Sediments, Technical Guidance 2003/08/20
Site-specific criteria Establishing Site Specific Aquatic Life Criteria Equal to Natural Background (Tudor Davies Memo) (PDF) (3 pp, 125K) 1997/11/05
Site-specific criteria Guidelines for Deriving Numerical Aquatic Site-Specific Water Quality Criteria by Modifying National Criteria 1984/12/01 600/S3-84-099
Standards, General Strategy for Water Quality Standards and Criteria 2003/08/03 823-R-03-010
Standards, General Assessment of the Water Quality Standards Development and Review Process (PDF) (83 pp, 508K) 2000/10/01
Standards, General Advanced Notice of Proposed Rulemaking for Water Quality Standards (PDF) (65 pp, 593K) 1998/07/07 Federal Register Vol. 63, No.129 Pages 36741-36806
Standards, General Water Quality Criteria and Standards Plan: Priorities for the Future (PDF) (60 pp, 121K) 1998/06/01 822-R-98-003
Standards, General Water Quality Criteria and Standards for the 21st Century: Proceedings, 4th National Conference, September 13-15, 1994 (PDF) (252 pp, 82.3MB) 1994/09/01 820/R-95-001
Standards, General Water Quality Standards for the 21st Century: Proceedings of the Third National Conference, August 31-September 3, 1992, Las Vegas, Nevada (PDF), December, 1992 (16.4MB) 1992/12/01 823/R-92-009
Standards, General Water Quality Standards, Memorandum from Jack Raven (PDF) (2 pp, 105K) 1984/02/02
Submitting new or revised water quality standards to EPA Information for States and Tribes on submittal of new and/or revised water quality standards to U.S. EPA for review under section 303(c) of the Clean Water Act and Federal regulations at 40 CFR 131 (PDF) (7 pp, 32K) 2007/09/13  
TMDL Guidance for Water Quality-based Decisions: The TMDL Process 1991/04/01 440/4-91-001
Toxic criteria Technical Support Document of Water Quality-Based Toxics Control (PDF) (335 pp, 26.6MB) 1991/03/01 823/R-88-100
Toxic criteria Memorandum from LaJuana Wilcher Announcing Development of Federal Rulemaking to Promulgate State Water Quality Standards (National Toxics Rule) (PDF) (5 pp, 426K) 1990/01/26
Toxic criteria Compliance with CWA Section 303(c)(2)(B), Memorandum from Martha Prothro (PDF) (3 pp, 334K) 1989/06/19
Toxic criteria Guidance for State Implementation of Water Quality Standards for CWA Section 303(c)(2)(B), Memorandum from Rebecca Hanmer (PDF) (22 pp, 1.4MB) 1988/12/12 823-R-88-100
Toxic criteria Selection of Water Quality Criteria in State Water Quality Standards, Memorandum from Edwin Johnson (PDF) (4 pp, 592K) 1985/02/28
Toxic criteria Recalculation of State Toxic Criteria from October 1, 1982 (PDF) (83 pp, 3.4MB) 1982/10/01
Toxic criteria Toxic Criteria Recommendations, Memorandum from Joseph Krivak re. November 28, 1980 (PDF) (2 pp, 83K) 1981/08/28
Tribes Strategy for Reviewing Tribal Eligibility Applications to Administer EPA Regulatory Programs (Strategy for Treatment in a Similar Manner to a State) (PDF) (38 pp, 534K) 2008/01/23
Tribes Final Section 106 Tribal Grant Guidance 2006/10/20 832-R-06-003
Tribes OST Expectations for Water Quality Standards for Indian Reservations for Tribes Treated as States, Memorandum from Tudor Davies (PDF) (5 pp, 246K) 1992/04/20
Tribes Guidance on Water Quality Standards and 401 Certification Programs Administered by Indian Tribes, Memorandum from Tudor Davies (PDF) (7 pp, 562K) 1991/12/31
Tribes Final WQS Regulation Amendment Concerning Indian Tribes, Memorandum from Tudor Davies (PDF) (5 pp, 294K) 1991/12/05
Tribes Reference Guide to Water Quality Standards for Indian Tribes (PDF) (3MB) 1990/01/02 440/5-90-002
Tribes Water Quality Standards Cooperative Agreements, Memorandum from David Sabock (PDF) (5 pp, 642K) 1989/08/22
Tribes Questions on Application of Federal Environmental Programs on Indian Lands, Letter to Mr. Dave Frohnmayer, Attorney General (PDF) (7 pp, 580K) 1988/09/09
Triennial Review Guidance: Coordinating CSO Long-Term Planning with Water Quality Standards Reviews (PDF) (79 pp, 498K) 2001/07/31 833-R-01-002
Triennial Review Three-Year Quality Standards Review, Memorandum from Patrick Tobin (PDF) (2 pp, 251K) 1983/09/06
Use Attainability Analysis Improving the Effectiveness of the Use Attainability Analysis Process, Memorandum from Ephraim King 2006/03/13
Use Attainability Analysis UAAs and Other Tools for Managing Designated Uses (PDF) (403 pp, 9.3MB) 2006/03/01 821-R-07-001
Use Attainability Analysis Water Quality Standards: Examples of Alternatives to Changing Long-term Designated Uses to Achieve Water Quality Goals (PDF) (14 pp, 830K) 2005/03/01
Use Attainability Analysis Technical Support Manual: Waterbody Surveys and Assessments for Conducting Use Attainability Analysis, Volumes 1-3 (PDF) (1983-84; 622 pp, 19.6MB) 1984/01/01 440/4-86-037
Use Attainment Framework for Incorporating Community Preferences in Use Attainment and Related Water Quality Decision-Making 2011/02/01 625/R-08/001F
Variances Request for Views on Allowable Duration of Water Quality Standards Variances, Memorandum from Catherine Winer (PDF) (4 pp, 242K) 1992/01/24
Variances National Assessment of State Variance Procedures: Report (PDF) (44 pp, 3MB) 1990/11/01
Variances Variances in Water Quality Standards, Memorandum from Edwin Johnson (PDF) (9K) 1985/03/15
Variances Applicability of the Part 25 "Public Participation" Regulations to the Approval of Variances from Water Quality Standards, Memorandum from Michele Corash (PDF) (5 pp, 248K) 1980/09/04
Variances Decision no. 58 of the General Counsel on Matters of Law Pursuant to 40 CFR Section 125.36(m) (PDF) (541K) 1977/03/29
Variances Decision no. 44 of the General Counsel on Matters of Law Pursuant to 40 CFR Section 125.35(m) (PDF) (341K) 1976/06/22
Variances and Downgrades Definitions of WQS Terms, Memorandum from Kenneth Mackenthun (PDF) (75K) 1979/07/03
Variances for Multiple Dischargers Developing Credible Rationales for Variances that Apply to Multiple Dischargers - Frequently Asked Questions (PDF) (7 pp, 449K)
2013/03/29 820-F-13-001
Waste Load Allocations Technical Guidance Manual for Performing Wasteload Allocations, Book 6, Design Conditions 1986/09/01 440487004
Water Quality-Based Approach Committing EPA's Water Program to Advancing the Watershed Approach, Memorandum from Tracy Mehan 2002/12/03
Water Quality State Authority to Allocate Water Quantities - Section 101(g) of the Clean Water Act (PDF) (4 pp, 387K) 1978/11/07
Waters of the US Clean Water Act Definition of “Waters of the United States” Current
Wetlands Numeric Water Quality Criteria for Wetlands (PDF) (51 pp, 2.8MB) 1991/07/08
Wetlands Water Quality Standards for Wetlands: National Guidance  1990/07/01 440/S-90-011
Wetlands Wetlands and 401 Certification: Opportunities for States and Eligible Indian Tribes  1989/04/01
Wetlands Clean Water Act Authority Over Wetlands, Memorandum from Cathy Winer (PDF) (2 pp, 277K) 1985/04/19
What is a New or Revised WQS What is a New or Revised Water Quality Standard Under CWA 303(c)(3)? - Frequently Asked Questions 2012/10/09 820F12017

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