Wyo. Code R. 020-0011-1
Effective Date: 07/21/1994 to 10/15/1998
Rule Type: Superceded Rules & Regulations
Reference Number: 020.0011.1.07211994
Section 1. Authority. These regulations are promulgated pursuant to W.S. 35-11-101 through 1304 specifically 302 (a) (i), and no person shall cause, threaten or allow violation of a surface water quality standard contained herein.
Section 2. Definitions. The following definitions supplement those definitions contained in section 35-11-103 of the Wyoming EnvironmeThe one hour average concentration. The EPA has determined that this value, if not exceeded more than once every three years on average, should not result in unacceptable effects on freshwater aquatic organisms and their uses. Acute values represent a response to a stimulus severe enough to induce a rapid reaction, typically in 96 hours or less. Appendix B contains acute values for certain pollutants.
(b) Agriculture - Water uses which include irrigation and/or stock watering.
(c) Best Management Practices - A practice or combination of practices that after problem assessment, examination of alternative practices and appropriate public participation, are determined to be the most technologically and economically feasible means of preventing or reducing nonpoint source pollution.
Best Management Practices (BMPS) are adopted in accordance with procedures outlined in the Wyoming Continuing Planning Process (CPP) after problem assessment, examination of alternative practices, and appropriate public participation. In instances where a conflict arises as to which practice or practices should be implemented, a committee consisting of the landowner, a representative of the Department of Environmental Quality, and a third, mutually acceptable party, shall be convened to resolve the conflict.
(d) Chronic Value - The four day average concentration. The EPA has determined that this value, if not exceeded more than once every three years, should not result in unacceptable effects on freshwater aquatic organisms and their uses. Chronic values represent a response to a continuous, long-term stimulus. Appendix B contains chronic values for certain pollutants.
(e) Cold Water Game Fish - Grayling (Thymallus arcticus), Northern Pike (Esox lucius), Salmon (Oncorhynchus spp.), Sauger (Stizostedion canadense), Tiger muskie (Esox Masquinongy), Trout (Salmo, Oncorhynchus, and Salvelinus spp.), Walleye (Stizostedion vitreum), and, Whitefish (Prospium williamsoni).
(f) Dissolved Oxygen - A measure of the amount of free oxygen in water.
(g) Effluent Limitations - Any restriction established by the state or by the administrator of the Environmental Protection Agency on quantities, rates and concentrations of chemical, physical, biological and other constituents which are discharged from point sources into waters of the state, including schedules of compliance.
(h) Environmental Protection Agency - The Federal Environmental Protection Agency (EPA).
(i) Ephemeral Stream - A stream which flows only in direct response to precipitation in the immediate watershed or in response to snow melt, and which has a channel bottom that is always above the prevailing water table.
(j) Eutrophic - Waters abundant in nutrients and having high rates of productivity frequently resulting in oxygen depletion below the surface layer.
(k) Existing Quality - The established chemical and biological water quality as of the date of promulgation of these regulations with recognition of the fact that water quality will tend to fluctuate on a seasonal and year-to-year basis depending upon natural fluctuations in water quantity.
(l) Fecal Coliform - Those species within the coliform bacteria group which are present in the gut or feces of warmblooded animals. The group includes organisms which are capable of producing gas from lactose broth in a suitable culture medium within 24 hours at 44.5 degrees C + .2 degrees C.
(m) Federal Act - The Federal Water Pollution Control Act (Clean Water Act) and subsequent amendments to that act.
(n) Full Body Contact Water Recreation - Any recreational or other surface water use in which there is contact with the water sufficient to pose a significant health hazard (i.e., water skiing, swimming).
(o) Game Fish - Bass (Micropterus spp.), Catfish (Ictalurus punctatus), Crappie (Pomoxis spp.), Grayling (Thymallus arcticus), Ling (Lota lota), Northern Pike (Esox lucius), Perch (Perca flavescens), Salmon (Oncorhynchus spp.), Sauger (Stizostedion canadense), Sunfish (Lepomis spp.), Tiger Muskie (Esox Masquinongy), Trout (Salmo, Oncorhynchus, and Salvelinus spp.), Walleye (Stizostedion vitreum), White Bass (Morone chrysops), and Whitefish (Prospium williamsoni).
(p) Intermittent Stream - A stream or part of a stream that is below the local water table for some part of the year, but is not a perennial stream.
(q) Main Stem - This term shall mean the major channel of a river or stream as shown on the latest and most detailed records of the Wyoming State Engineer.
(r) Micrograms Per Liter (ug/l) - Micrograms of solute per liter of solution equivalent to parts per billion (ppb) in liquids, assuming unit density.
(s) Milligrams Per Liter (mg/l) - Milligrams of solute per liter of solution equivalent to parts per million (ppm) in liquids, assuming unit density.
(t) Mixing Zone - A limited area or volume of a surface water body within which an effluent becomes thoroughly mixed with the water body.
(u) Nanograms Per Liter (ng/l) - Nanograms of solute per liter of solution equivalent to parts per trillion in liquids, assuming unit density.
(v) Natural - That condition which would exist without the measurable effects or measurable influence of man's activities.
(w) Natural Biotic Community - The population structures which were historically or normally present under a given set of chemical and physical conditions or which would potentially exist had not the habitat been degraded.
(x) Natural Water Quality - That quality of water which would exist without the measurable effects or measurable influence of man's activities.
(y) Nephelometric Turbidity Unit (NTU) - The standard unit used to measure the optical property that causes light to be scattered and absorbed rather than transmitted in straight lines through water, as measured by a nephelometer.
(z) Nongame Fish - All fish species except those listed in Section 2(o) above.
(aa) Nonpoint Source - Any source of pollution other than a point source as defined by W.S. 35-11-103(a)(x) and Section 2(dd) of these regulations and includes underground storage tanks.
(bb) pH - Term used to express the intensity of acid or alkaline conditions. A pH value of 7 at 25 degrees C is neutral, with pHs of less than 7 progressively more acid and pHs of greater than 7 progressively more basic (alkaline).
(cc) PicoCuries Per Liter (pCi/l) - A term describing the radiation level of water or solutions. A picocurie is equal to 10-12 curie; a curie is defined as 3.7 x 10¹⁰ disintegrations per second.
(dd) Point Source - Any discernible, confined and discrete conveyance, including but not limited to any pipe, ditch, channel, conduit, well, discrete fissure, container, rolling stock, concentrated animal feeding operation or vessel or other floating craft, from which pollutants are or may be discharged, except those pollutant sources specifically identified as nonpoint in these regulations.
(ee) Salinity - The total mineral dissolved constituents, after carbonates have been converted to oxides, organics have been oxidized and bromine and iodine have been converted to chloride. This term is often used interchangeably with the term total dissolved solids.
(ff) Secondary Body Contact Recreation - Any recreational or other surface water use in which contact with water is either incidental or accidental and in which the probability of ingesting appreciable quantities of water is minimal, such as fishing, hunting and commercial and recreational boating.
(gg) Surface Waters of the State - All permanent and intermittent defined drainages and lakes, reservoirs, and wetlands which are not manmade retention ponds used for the treatment of municipal, agricultural or industrial waste; and all other bodies of surface water, either public or private which are wholly or partially within the boundaries of the State. Nothing in this definition is intended to expand the scope of the Environmental Quality Act, as limited in W.S. 35-11-1104.
(hh) Toxic Materials - Those materials or combinations of materials including disease causing agents, which, after discharge and upon exposure, ingestion, inhalation or assimilation into any organism, either directly from the environment or indirectly by ingestion through food chains, will, on the basis of information available to the director of the Wyoming Department of Environmental Quality cause death, disease, behavioral abnormalities, cancer, genetic malfunctions, physiological malfunctions (including malfunctions in reproduction) or physical deformations in such organisms or their offspring.
(ii) Tributary - Those streams or stream segments which flow into or contribute water to another stream, stream segment or other water body.
(jj) Undesirable Aquatic Life - Organisms generally associated with degraded or eutrophic conditions. These may include the following organisms where they have replaced members of the natural biotic community: nongame fish, bluegreen algae, certain diatoms, fungi, tubificid worms, and certain syrphid flies.
(kk) Warm Water Game Fish - Bass (Micropterus spp.), Catfish (Ictalurus punctatus), Crappie (Pomoxis spp.), Ling (Lota lota), Perch (Perca flavescens), Sunfish (Lepomis spp.), and White Bass (Morone Chrysops).
(ll) Wetlands - Those areas that are naturally inundated by surface or groundwater at a frequency and duration sufficient to support, and that under normal circumstances do support, a prevalence of vegetation typically adapted for life in a saturated soil condition. Wetlands generally include swamps, marshes, bogs and similar areas.
(mm) Wyoming Continuing Planning Process (CPP) - A planning process involving public participation and political debate and including policies, procedures and programs that result in the definition and implementation of actions that lead to the prevention, reduction and abatement of all forms of water pollution and for the protection and enhancement of water uses in the State of Wyoming. The CPP is continuous in time and is designed to respond to changes in conditions and attitudes. Certified and approved state and areawide water quality management plans prepared pursuant to section 208 of the federal act describe elements of the CPP and are outputs of the CPP. Such plans include but are not limited to the following:
(nn) Wyoming Surface Waters - Shall have the same meaning as 'surface waters of the State' defined in Section 2gg.
(oo) Zone of Passage - A continuous water route which joins segments of a Surface Water body above and below a mixing zone.
(pp) 404 Permit - The permit program established by Section 404 of the Federal Act to regulate the discharge of dredged or fill materials to surface waters of the United States.
Section 3. Water Uses. The objectives of the Wyoming pollution control program are outlined in W.S. 35-11-102 and are specifically designed to maintain the best possible quality of waters commensurate with the following uses: (a)
Agriculture;
(b) Protection and propagation of fish and wildlife;
(d) Human consumption;
(e) Recreation;
(f) Scenic value;
and, to achieve the goal of the federal act, which is to achieve, wherever attainable, surface water quality which provides for the protection and propagation of fish, shell fish, wildlife, and recreation in and on the water.
Section 4. Surface Water Classes and Uses. There are four classes of surface water in Wyoming (see Appendix A for listing):
(a) Class 1 - Those surface waters in which no further water quality degradation by point source discharges other than from dams will be allowed. Nonpoint sources of pollution shall be controlled through implementation of appropriate best management practices. In designating class 1 waters, the Environmental Quality Council shall consider water quality, aesthetic, scenic, recreational, ecological, agricultural, botanical, zoological, municipal, industrial, historical, geological, cultural, archaeological, fish and wildlife, the presence of significant quantities of developable water and other values of present and future benefit to the people.
(b) Class 2 - Those surface waters, other than those classified as class 1, which are determined to:
(i) Be presently supporting game fish; or
(ii) Have the hydrologic and natural water quality potential to support game fish; or
(iii) Include nursery areas or food sources for game fish.
(c) Class 3 - Those surface waters, other than those classified as class 1, which are determined to:
(i) Be presently supporting nongame fish only; or
(ii) Have the hydrologic and natural water quality potential to support nongame fish only; or
(iii) Include nursery areas or food sources for nongame fish only.
(d) Class 4 - Those surface waters, other than those classified as class 1, which are determined to not have the hydrologic or natural water quality potential to support fish and include all intermittent and ephemeral streams. Class 4 waters shall receive protection for agriculture uses and wildlife watering.
(e) Prior to proposing any changes in water classifications, the Department of Environmental Quality shall notify in writing local water users including the water commissioner, soil conservation committee, irrigation districts, county commissioners, and county ASCS.
In addition, the Department of Environmental Quality shall notify in writing the Wyoming State Engineer, the Wyoming Water Development Commission, and the Wyoming Game and Fish Department.
All class 1 and 2 waters are designated as coldwater game fisheries unless identified as a warmwater game fishery by a 'ww' notation in Appendix A.
Section 5. Standards Enforcement. The numerical and narrative standards contained within these regulations shall be used to establish effluent limitations for those discharges requiring control via permits to discharge in the case of point sources and best management practices in the case of nonpoint sources. If no permit or best management practice has been issued or implemented for a pollution source the state may, in addition to other appropriate legal action, take direct action to enforce these standards.
The processes used to implement the standards are described in various implementation documents adopted by the department. Such documents are adopted with full public participation and include, but are not limited to, the antidegradation policy, the Wyoming continuing planning process (CPP), the wasteload allocation manual, best management practices, and the toxics control strategy.
Compliance with the conditions of these regulations does not exempt any discharger from the penalty provisions of W.S. 35-11-901.
Section 6. Interstate Compacts, Court Decrees and Water Rights. The department shall, after review and conference with the State Engineer, make recommendations to the State Engineer concerning proposed new diversions which could cause violations of these regulations.
(a) No new point sources, other than dams, may discharge, and no existing point sources, other than dams, may increase their quantity of pollution discharge, to any water designated as class 1.
(b) The department shall impose whatever controls are necessary on point source discharges to tributaries of class 1 waters. Such discharges shall not degrade the quality of any class 1 water below its existing quality.
(c) Nonpoint source discharges of pollution to class 1 waters or tributaries of class 1 waters shall be controlled by application of best management practices adopted in accordance with the Wyoming continuing planning process. For class 1 waters, best management practices will maintain existing quality.
Section 8. Antidegradation. Water uses in existence on June 27, 1979 and the level of water quality necessary to protect those uses shall be maintained and protected. Those surface waters not designated as class 1, but whose quality is better than these standards, shall be maintained at that higher quality. However, after full intergovernmental coordination and public participation the Wyoming Department of Environmental Quality may issue a permit for or allow any project or development which would constitute a new source of pollution, or an increased source of pollution, to these waters as long as the following conditions are met:
(a) The quality is not lowered below these standards;
(b) All existing water uses are fully maintained and protected;
(c) The highest statutory and regulatory requirements for all new and existing point sources and all cost effective and reasonable best management practices for nonpoint sources have been achieved; and
(d) The lowered water quality is necessary to accommodate important economic or social development in the area in which the waters are located.
Section 9. Mixing Zones. Except for Sections 14, 15, 16, 17 and 28 of these regulations, compliance with water quality standards shall be determined after allowing reasonable time for mixing. Except for the zone of initial dilution, which is the initial 10% of the mixing zone, the mixing zone shall not contain pollutant concentrations that exceed the acute aquatic life values (see Appendix B). In addition, there shall be a zone of passage around the mixing zone which shall not contain pollutant concentrations that exceed the chronic aquatic life values (see Appendix B).
Section 10. Testing Procedures. For determination of the parameters involved in the standards, analyses will be in accord with test procedures defined pursuant to: Title 40, Code of Federal Regulations, Part 136, or any modifications thereto. For test procedures not listed in the Code of Federal Regulations, test procedures outlined in the latest editions of: EPA Methods for Chemical Analysis of Water and Wastes; or, Standard Methods for the Examination of Water and Wastewaters; or, A.S.T.M. Standards, Part 31, Water shall be used.
The analytical technique for total uranium (as U) shall be the fluorometric method as referenced in Methods for Determination of Radioactive Substances in Water and Fluvial Sediments, Techniques of Water - Resource Investigations of the U.S. Geological Survey, Book 5, Chapter A-5, pp. 83 - 92.
Where standard methods of testing have not been established, the suitability of testing procedures shall be determined by the department and the EPA using defensible scientific methods.
Section 11. Flow Conditions.
(a) Water Quality Standards shall apply at all times except during periods of low flow. Low flow can be determined by: 1) using the 7Q10 (the minimum 7 consecutive day flow which has the probability of occurring once in 10 years) for acute exposures, 2) the EPA's biologically based flow method which determines a 4 day, 3 year low flow for chronic exposures and a 1 day, 3 year low flow for acute exposures (ref: Technical Guidance Manual For Performing Waste Load Allocation; Book VI, Design Conditions: Chapter 1, Stream Design Flow for Steady-State Modeling, August 1986, USEPA), or 3) other defensible scientific methods. Whatever method is selected for a specific situation, application of the standards will conform to the magnitude, frequency, and duration provisions as described in these standards.
(b) During periods when stream flows are less than the minimums described above, the department may, in consultation with the Wyoming Game and Fish Department, require dischargers to institute operational modifications as necessary to insure the protection of aquatic life.
(c) Sections 14, 15, 16, 17, and 28 shall apply at all stream-flow conditions.
Section 12. Protection of Wetlands. Point or nonpoint sources of pollution shall not cause the destruction, damage, or impairment of naturally occurring wetlands except when mitigated through an authorized wetlands mitigation process. However, this section does not apply to wetlands created by point or nonpoint sources; nor are such wetlands required to be maintained through continuation of such discharges.
Section 13. Toxic Materials - Except for those substances referenced in Sections 21 (e) and (f), toxic materials attributable to or influenced by the activities of man shall not be present in any Wyoming surface water in concentrations or combinations which constitute 'Pollution' as that term is defined in W.S. 35-11-103(C)(i).
Section 14. Dead Animals and Solid Waste. In no case shall dead animals of any description be placed or allowed to remain in Wyoming surface waters or be placed or allowed to remain in any location which would result in contamination or threaten contamination of Wyoming surface water.
Except as authorized through a '404 permit', solid waste shall not be placed or allowed to remain in surface waters of the state, nor shall solid wastes be placed or allowed to remain in any location which would cause or threaten contamination of Wyoming surface waters.
Section 15. Settleable Solids. In all Wyoming surface waters, substances attributable to or influenced by the activities of man that will settle to form sludge, bank or bottom deposits shall not be present in quantities which could result in significant aesthetic degradation, significant degradation of habitat for aquatic life or adversely affect public water supplies, agricultural or industrial water use, plant life or wildlife.
Section 16. Floating and Suspended Solids. In all Wyoming surface waters, floating and suspended solids attributable to or influenced by the activities of man shall not be present in quantities which could result in significant aesthetic degradation, significant degradation of habitat for aquatic life, or adversely affect public water supplies, agricultural or industrial water use, plant life or wildlife.
Section 17. Taste, Odor and Color. No class 1, 2, or 3 waters shall contain substances attributable to or influenced by the activities of man that produce taste, odor and color or that would:
(a) Of themselves or in combination, impart an unpalatable or off-flavor in fish flesh;
(b) Visibly alter the natural color of the water or impart color to skin, clothing, vessels or structures;
(c) Produce detectable odor; or
(d) Directly or through interaction among themselves, or with chemicals used in existing water treatment processes, result in concentrations that will impart undesirable taste or odor to public water supplies.
Section 18. Human Health. In all class 1 and 2 waters, the human health values listed in Appendix B shall not be exceeded.
In certain waters, the criteria listed in Appendix B may not be appropriate due to unique physical or chemical conditions. In such cases, human health values may be determined by use of the site-specific procedures outlined in the references listed in Appendix E.
Section 19. Industrial Water Supply. All Wyoming surface waters which have the natural water quality potential for use as an industrial water supply shall be maintained at a quality which allows continued use of such waters for industrial purposes.
Degradation of such waters shall not be of such an extent to cause a measurable increase in raw water treatment costs to the industrial user(s).
Unless otherwise demonstrated, all Wyoming surface waters have the natural water quality potential for use as an industrial water supply.
Section 20. Agricultural Water Supply. All Wyoming surface waters which have the natural water quality potential for use as an agricultural water supply shall be maintained at a quality which allows continued use of such waters for agricultural purposes.
Degradation of such waters shall not be of such an extent to cause a measurable decrease in crop or livestock production.
Unless otherwise demonstrated, all Wyoming surface waters have the natural water quality potential for use as an agricultural water supply.
(a) Ammonia - The toxicity of ammonia varies with pH and temperature and the applicable limitations are included in the charts in Appendix C.
(b) Specific numeric standards for a number of toxicants are listed in the aquatic life 'acute value' and 'chronic value' columns in Appendix B. These standards apply to all class 1, 2, and 3 waters. For these pollutants, the chronic value (four day average concentration) and the acute value (one hour average concentration) shall not be exceeded more than once every three years.
(c) Others - For those pollutants not listed in Appendix B or C, maximum allowable concentrations shall be determined through the bioassay procedures outlined in the references listed in Appendix E.
(d) In certain waters, the criteria listed in Appendix B or C may not be appropriate due to unique physical or chemical conditions. In such cases, acute and chronic values may be determined by use of the site-specific procedures outlined in the references listed in Appendix E.
(e) Toxic substances specifically designed to kill or eliminate problem causing aquatic life (such as mosquito larvae or heavy plant growth in irrigation ditches) may be added to surface waters of the state provided such substances are administered in accordance with label directions. However, compliance with label directions shall not exempt any person from the penalty provisions of W.S. 35-11-901.
(f) This section shall not apply to the use of fish toxicants by the Wyoming Game and Fish Department provided such toxicants are administered in accordance with label directions. However, compliance with label directions shall not exempt that agency for the penalty provisions of W.S. 35-11-901 should non-target species or non-target areas be affected.
(a) In class 1 and 2 waters the radiological limits established in the most recent Federal Primary Drinking Water Standards published by EPA or its successor agency shall not be exceeded.
(b) In class 3 and 4 waters the total radium 226 concentration shall not exceed 60 pCi/l.
(c) In all Wyoming Surface Waters radioactive materials shall not be present in the water or in the sediments in amounts which could cause harmful accumulations of radioactivity in plant, wildlife, stock, or aquatic life.
(a) In all class 1 and 2 waters which are cold-water fisheries, the discharge of substances attributable to or influenced by the activities of man shall not be present in quantities which would result in a turbidity increase of more than 10 nephelometric turbidity units (NTUs).
(b) In all class 3 waters and in class 1 and 2 waters which are warmwater fisheries, the discharge of substances attributable to or influenced by the activities of man shall not be present in quantities which would result in a turbidity increase of more than 15 NTUs.
(c) An exception to paragraphs (a) and (b) of this section shall apply to the North Platte River from Guernsey Dam to the Nebraska line during the annual 'silt run' from Guernsey Dam.
Section 24. Dissolved Oxygen. In all class 1 and 2 waters, wastes attributable to or influenced by the activities of man shall not be present in amounts which will result in death or injury to existing aquatic life or which will result in a dissolved oxygen content of less than that presented on the chart in Appendix D.
(a) For class 1, 2 and 3 waters, effluent attributable to or influenced by the activities of man shall not be discharged in amounts which change natural water temperatures to levels which are deemed to be harmful to existing aquatic life.
(b) In all class 1 and 2 waters which are cold water game fisheries, effluent attributable to or influenced by the activities of man shall not be discharged in amounts which will result in a change of more than 2 degrees F (1.1 degree C) in existing temperatures.
(c) In all class 3 waters, and in class 1 and 2 waters which are warm water game fisheries, effluent attributable to or influenced by the activities of man shall not be discharged in amounts which will result in a change of more than 4 degrees F (2.2 degrees C) in existing temperatures.
(d) The maximum allowable stream temperature will be the maximum natural daily stream temperature plus the allowable change, provided that this temperature is not lethal to existing fish life, which is considered to be 78 degrees F (25.6 degrees C) in the case of cold water fisheries and 90 degrees F (32.2 degrees C) in the case of warm water fisheries and class 3 waters.
(e) With the exception of the provisions of sections 9 and 11 of these regulations, temperature standards shall apply at all times and at all depths of the receiving water and may not be violated at any time or at any depth.
(f) There shall be no artificially induced temperature change over spawning beds in any class 1, 2, or 3 waters.
(g) The various requirements of this section may be waived only under the provisions of section 316(a) of the federal act.
Section 26. pH. For all Wyoming surface waters, wastes attributable to or influenced by the activities of man shall not be present in amounts which will cause the pH to be less than 6.5 or greater than 9.0 standard units.
(a) During the entire year, fecal coliform concentrations shall not exceed a geometric mean of 200 fecal coliform groups per 100 milliliters (based on a minimum of not less than 5 samples obtained during separate 24 hour periods for any 30 day period), nor shall 10 percent of the samples exceed 400 groups per 100 milliliters during any 30 day period in any class 4 water and at all public water supply intakes.
(b) During the recreation season, (May 1, through September 30) fecal coliform concentrations shall not exceed a geometric mean of 200 fecal coliform groups per 100 milliliters (based on a minimum of not less than 5 samples obtained during separate 24 hour periods for any 30 day period), nor shall 10 percent of the samples exceed 400 groups per 100 milliliters during any 30 day period in all Wyoming surface waters (except those listed in (a) and (c)) and are hereby classified as full body contact recreation waters.
(c) During the recreation season (May 1, through September 30), fecal coliform concentrations shall not exceed a geometric mean of 1,000 fecal coliform groups per 100 milliliters (based on a minimum of not less than 5 samples obtained during separate 24 hour periods for any 30 day period), nor shall 10 percent of the samples exceed 2,000 groups per 100 milliliters during any 30 day period in the following waters which are hereby classified as secondary body contact recreation waters:
(i) The North Platte River from the Casper sewage treatment plant outfall to the Douglas water treatment plant intake.
(ii) The Hams Fork River below the Kemmerer sewage treatment plant outfall.
(iii) The Popo Agie River below the Lander sewage treatment plant outfall.
(iv) Bitter Creek below the Powell sewage treatment plant outfall.
(v) The Little Snake River below the Baggs sewage treatment plant outfall.
(vi) The Big Horn River below the Worland sewage treatment plant outfall.
(vii) North Piney Creek below the Big Piney sewage treatment plant outfall.
(viii) Clear Creek below the Buffalo sewage treatment plant outfall.
(ix) Chugwater Creek below the Chugwater sewage treatment plant outfall.
(x) The Belle Fourche River below the Hulett sewage treatment plant outfall.
(xi) The Powder River below the Kaycee sewage treatment plant outfall.
(xii) Rawhide Creek below the Lingle sewage treatment plant outfall.
(xiii) The Shoshone River from the Cody sewage treatment plant outfall to the Lovell water treatment plant intake.
(xiv) Sage Creek below the Frannie sewage treatment plant outfall.
(xv) Muddy Creek below the Marbleton sewage treatment plant outfall.
(xvi) The Medicine Bow River below the Medicine Bow sewage treatment plant outfall.
(xvii) The Smiths Fork River below the Mountain View sewage treatment outfall.
(xviii) The Ocean Lake #6 Drain below the Pavillion sewage treatment plant outfall.
(xix) Pine Creek below the Pinedale sewage treatment plant outfall.
(xx) Rock Creek below the Rock River sewage treatment plant outfall.
(xxi) Tensleep Creek below the Tensleep sewage treatment plant outfall.
(xxii) The North Platte River from the Torrington sewage treatment plant outfall to the Nebraska state line.
(xxiii) Wheatland Creek below the Wheatland sewage plant outfall.
(xxiv) The Little Wind River below the St. Stephens sewage treatment plant outfall.
(xxv) The Wind River below the Riverton sewage treatment plant outfall to Boysen Reservoir.
Section 28. Undesirable Aquatic Life. All Wyoming surface waters shall be free from substances and conditions or combinations thereof which are attributable to municipal, industrial or other dischargers or agricultural practices, in concentrations which produce undesirable aquatic life.
Section 29. Oil and Grease. In all Wyoming surface waters, substances attributable to or influenced by the activities of man shall not be present in amounts which would cause: The oil and grease content to exceed 10 mg/l; or formation of a visible sheen; or visible deposits on the bottom or shoreline; or, damage or impairment of the normal growth, function or reproduction of human, animal, plant or aquatic life.
Section 30. Total Dissolved Gases. In all class 1, 2 and 3 waters, the total dissolved gas concentration below manmade dams shall not exceed 110 percent of the saturation value for gases at the existing atmospheric and hydrostatic pressures.
The State of Wyoming is a member of the Colorado River Basin Salinity Control Forum, which includes all states in the Colorado River Basin. This forum has adopted a salinity control program for the basin which has been adopted as Chapter VI of the Wyoming Water Quality Rules and Regulations.
Appendix A
Waters are listed within each drainage in upstream order. An indented entry is tributary to the previous entry.
All surface waters located within the boundaries of national parks and congressionally designated wilderness areas are class 1 waters. Such class 1 designation always takes precedence over the classification given in the listing. For example, Dinwoody Creek is shown as a class 2 water; however, the upper portions are within a wilderness area and those portions are class 1. The portion below the wilderness boundary is class 2.
Except for waters in wilderness areas and waters listed in this Appendix, all waters within the boundaries of national forests are designated as class 2.
All surface waters located within the Great Divide Basin are designated as class 4.
The waters listed are all waters which are named on the USGS 1:500,000 hydrologic map of Wyoming and those previously classified by the department. Unless there is other information available, any unlisted water shall have the same classification as the first listed water to which it is a tributary.