1. (a) Classes and subclasses of use of the state's water protected by criteria set out under (b) of this section are

   1. (1) fresh water

      1. (A) water supply

         1. (i) drinking, culinary, and food processing;
         2. (ii) agriculture, including irrigation and stock watering;
         3. (iii) aquaculture;
         4. (iv) industrial;

      2. (B) water recreation

         1. (i) contact recreation;
         2. (ii) secondary recreation;
      3. (C) growth and propagation of fish, shellfish, other aquatic life, and wildlife; and

   2. (2) marine water

      1. (A) water supply

         1. (i) aquaculture;
         2. (ii) seafood processing;
         3. (iii) industrial;

      2. (B) water recreation

         1. (i) contact recreation;
         2. (ii) secondary recreation;
      3. (C) growth and propagation of fish, shellfish, other aquatic life, and wildlife; and
      4. (D) harvesting for consumption of raw mollusks or other raw aquatic life.

2. (b) Except as modified by or under 18 AAC 70.220 or 18 AAC 70.235, the water quality criteria set out in the following table, and in the Alaska Water Quality Criteria Manual for Toxic and Other Deleterious Organic and Inorganic Substances, dated April 1, 2026 and adopted by reference, in combination with the classes and subclasses of water use set out in (a) of this section, constitute the water quality standards for a particular waterbody; the water quality standards regulate human activities that result in alterations to waters within the state's jurisdiction: Water Quality Standards for Designated Uses POLLUTANT & WATER USE CRITERIA (1) COLOR, FOR FRESH WATER USES (see note 8) (A) Water supply

   1. (i) drinking, culinary, and food processingMay not exceed 15 color units or
   2. (ii) agriculture, including irrigation and stock wateringNot applicable.(A) Water Supply
   3. (iii) aquacultureMay not exceed 50 color units or
   4. (iv) industrialMay not cause detrimental effects
   5. (i) contact recreationSame as (l)(A)(i).(B) Water Recreation
   6. (ii) secondary recreationMay not interfere with or make the
   7. (i) drinking, culinary, and food processingIn a 30-day period, the geometric mean
   8. (ii) agriculture, including irrigation and stock wateringIn a 30-day period, the geometric mean
   9. (iii) aquacultureFor products normally cooked, the geo-
   10. (iv) industrialWhere worker contact is present, the
   11. (i) contact recreationIn a 30-day period, the geometric mean
   12. (ii) secondary recreationIn a 30-day period, the geometric mean
   13. (i) drinking, culinary, and food processingDissolved oxygen (D.O.) must be great-
   14. (ii) agriculture, including irrigation and stock wateringD.O. must be greater than 3 mg/l
   15. (iii) aquacultureD.O. must be greater than 7 mg/l
   16. (iv) industrialMay not cause detrimental effects on
   17. (i) contact recreationD.O. must be greater than or equal
   18. (ii) secondary recreationSame as (3)(B)(1).(C) Growth and Propagation of Fish, Shellfish, Other Aquatic Life, and WildlifeD.O. must be greater than 7 mg/l in
   19. (i) drinking, culinary, and food processingTotal dissolved solids (TDS) from
   20. (ii) agriculture, including irrigation and stock wateringTDS may not exceed 1,000 mg/l.
   21. (iii) aquacultureTDS may not exceed 1,000 mg/l. A
   22. (iv) industrialNo amounts above natural conditions
   23. (i) contact recreationNot applicable.(B) Water Recreation
   24. (ii) secondary recreationNot applicable.(C) Growth and Propagation of Fish, Shellfish, Other Aquatic Life, and WildlifeSame as (4)(A)(iii).
   25. (i) drinking, culinary, and food processingMay not cause a visible sheen upon
   26. (ii) agriculture, including irrigation and stock wateringMay not cause a visible sheen
   27. (iii) aquacultureTotal aqueous hydrocarbons (TAqH)
   28. (iv) industrialMay not make the water unfit
   29. (i) contact recreationMay not cause a film, sheen, or dis-
   30. (ii) secondary recreationSame as (5)(B)(i).(C) Growth and Propagation of Fish, Shellfish, Other Aquatic Life, and WildlifeSame as (5)(A)(iii).
   31. (i) drinking, culinary, and food processingMay not be less than 6.0 or greater than
   32. (ii) agriculture, including irrigation and stock wateringMay not be less than 5.0 or greater than
   33. (iii) aquacultureMay not be less than 6.5 or greater than
   34. (iv) industrialMay not be less than 5.0 or greater than
   35. (i) contact recreationMay not be less than 6.5 or greater than
   36. (ii) secondary recreationSame as (6)(A)(iv).(C) Growth and Propagation of Fish, Shellfish, Other Aquatic Life, and WildlifeMay not be less than 6.5 or greater than
   37. (i) drinking, culinary, and food processingMay not exceed the concentrations spe-
   38. (ii) agriculture, including irrigation and stock wateringSame as (7)(A)(i).(A) Water Supply
   39. (iii) aquacultureSame as (7)(A)(i) except that concentra-
   40. (iv) industrialSame as (7)(A)(i).(B) Water Recreation
   41. (i) contact recreationSame as (7)(A)(i).(B) Water Recreation
   42. (ii) secondary recreationSame as (7)(A)(i).(C) Growth and Propagation of Fish, Shellfish, Other Aquatic Life, and WildlifeSame as (7)(A)(iii).
   43. (i) drinking, culinary, and food processingMay not, alone or in combination with
   44. (ii) agriculture, including irrigation and stock wateringMay not be present in quantities to
   45. (iii) aquacultureMay not, alone or in combination
   46. (iv) industrialSame as (8)(A)(iii).(B) Water Recreation
   47. (i) contact recreationSame as (8)(A)(i).(B) Water Recreation
   48. (ii) secondary recreationSame as (8)(A)(i).(C) Growth and Propagation of Fish, Shellfish, Other Aquatic Life, and WildlifeMay not, alone or in combination
   49. (i) drinking, culinary, and food processingNo measurable increase in concen-
   50. (ii) agriculture, including irrigation and stock wateringFor sprinkler irrigation, water must be
   51. (iii) aquacultureNo imposed loads that will interfere
   52. (iv) industrialSame as (9)(A)(iii).(B) Water Recreation
   53. (i) contact recreationSame as (9)(A)(i).(B) Water Recreation
   54. (ii) secondary recreationMay not pose hazards to incidental
   55. (i) drinking, culinary, and food processingMay not exceed 15° C.(A) Water Supply
   56. (ii) agriculture, including irrigation and stock wateringMay not exceed 30° C.(A) Water Supply
   57. (iii) aquacultureMay not exceed 20° C at any time. The
   58. (iv) industrialMay not exceed 25° C.(B) Water Recreation
   59. (i) contact recreationSame as (10)(A)(ii).(B) Water Recreation
   60. (ii) secondary recreationNot applicable.(C) Growth and Propagation of Fish, Shellfish, Other Aquatic Life, and WildlifeSame as (10)(A)(iii).
   61. (i) drinking, culinary, and food processingThe concentration of substances in water
   62. (ii) agriculture, including irrigation and stock wateringThe concentration of substances in water
   63. (iii) aquacultureSame as (11)(C).(A) Water Supply
   64. (iv) industrialConcentrations of substances that pose
   65. (i) contact recreationThe concentration of substances in water
   66. (ii) secondary recreationConcentrations of substances that pose
   67. (i) drinking, culinary, and food processingMay not exceed 5 nephelometric turbidity
   68. (ii) agriculture, including irrigation and stock wateringMay not cause detrimental effects on
   69. (iii) aquacultureMay not exceed 25 NTU above natural
   70. (iv) industrialMay not cause detrimental effects
   71. (i) contact recreationMay not exceed 5 NTU above natural
   72. (ii) secondary recreationMay not exceed 10 NTU above natural
   73. (i) aquacultureMay not exceed 50 color units or the
   74. (ii) seafood processingMay not exceed 15 color units or the
   75. (iii) industrialNot applicable.(B) Water Recreation
   76. (i) contact recreationSame as (13)(A)(ii).(B) Water Recreation
   77. (ii) secondary recreationSurface waters must be free of sub-
   78. (i) aquacultureFor products normally cooked, the geo-
   79. (ii) seafood processingIn a 30-day period, the geometric mean
   80. (iii) industrialWhere worker contact is present, the
   81. (i) contact recreationIn a 30-day period, the geometric mean of
   82. (ii) secondary recreationIn a 30-day period, the geometric mean
   83. (i) aquacultureSurface dissolved oxygen (D.O.) concen-
   84. (ii) seafood processingNot applicable.(A) Water Supply
   85. (iii) industrialNot applicable.(B) Water Recreation
   86. (i) contact recreationSame as (15)(A)(i).(B) Water Recreation
   87. (ii) secondary recreationSame as (15)(A)(i).(C) Growth and Propagation of Fish, Shellfish, Other Aquatic Life, and WildlifeSame as (15)(A)(i).(D) Harvesting for Consumption of Raw Mollusks or Other Raw Aquatic LifeSame as (15)(A)(i).
   88. (i) aquacultureHuman-induced alteration may not
   89. (ii) seafood processingNot applicable.(A) Water Supply
   90. (iii) industrialNo amounts above natural conditions
   91. (i) contact recreationNot applicable.(B) Water Recreation
   92. (ii) secondary recreationNot applicable.(C) Growth and Propagation of Fish, Shellfish, Other Aquatic Life, and WildlifeMaximum allowable variation above nat-
   93. (i) aquacultureTotal aqueous hydrocarbons (TAqH) in

   the natural condition, whichever

   is greater.(A) Water Supply

   the natural condition, whichever

   is greater.(A) Water Supply

   on established water supply treat-

   ment levels.(B) Water Recreation

   water unfit or unsafe for the use.(C) Growth and Propagation of

   Fish, Shellfish, Other Aquatic

   Life, and WildlifeColor or apparent color may not reduce

   the depth of the compensation point

   for photosynthetic activity by more

   than 10% from the seasonally estab-

   lished norm for aquatic life. For all

   waters without a seasonally

   established norm for aquatic life,

   color or apparent color may not

   exceed 50 color units or the natural

   condition, whichever is greater.

   Water Quality Standards for Designated Uses

   POLLUTANT & WATER USE CRITERIA (2) BACTERIA, FOR FRESH

   WATER USES (see note 1) (A) Water supply

   may not exceed 20 fecal coliform/100

   ml, and not more than 10% of the sam-

   ples may exceed 40 fecal coliform/100

   ml. For groundwater, the fecal coliform

   concentration must be less than 1 fe-

   cal coliform/100 ml, using the fecal

   coliform Membrane Filter Technique,

   or less than 3 fecal coliform/100 ml,

   using the fecal coliform most probable

   number (MPN) technique.(A) Water Supply

   may not exceed 200 fecal coliform/100

   ml, and not more than 10% of the irriga-

   tion and stock samples may exceed 400

   fecal coliform/100 ml. For products not

   normally cooked and for dairy sanitation

   of unpasteurized products, the criteria

   for drinking water supply, (2)(A)(i),

   apply.(A) Water Supply

   metric mean of samples taken in a 30-

   day period may not exceed 200 fecal

   coliform/100 ml, and not more than 10%

   of the samples may exceed 400 fecal

   coliform /100 ml. For products not nor-

   mally cooked, the criteria for drinking

   water supply, (2)(A)(i), apply.(A) Water Supply

   geometric mean of samples taken in a

   30-day period may not exceed 200 fecal

   coliform/100 ml, and not more than 10%

   of the samples may exceed 400 fecal

   coliform/100 ml.(B) Water Recreation

   of samples may not exceed 126 Esche-

   richia coli (E. coli) colony forming

   units (CFU)/100 ml, and not more than

   10% of the samples may exceed a stat-

   istical threshold value (STV) of 410 E.

   coli CFU/100 ml.(B) Water Recreation

   of samples may not exceed 200 fecal

   coliform/100 ml, and not more than 10%

   of the total samples may exceed 400

   fecal coliform/100 ml.(C) Growth and Propagation of

   Fish, Shellfish, Other Aquatic

   Life, and WildlifeNot applicable.

   Water Quality Standards for Designated Uses

   POLLUTANT & WATER USE CRITERIA (3) DISSOLVED GAS, FOR

   FRESH WATER USES (A) Water supply

   er than or equal to 4 mg/l (this does not

   apply to lakes or reservoirs in which sup-

   plies are taken from below the thermo-

   cline, or to groundwater).(A) Water Supply

   in surface waters.(A) Water Supply

   in surface waters. The concentration

   of total dissolved gas may not exceed

   110% of saturation at any point of

   sample collection.(A) Water Supply

   established water supply treatment

   levels.(B) Water Recreation

   to 4 mg/l.(B) Water Recreation

   waters used by anadromous or resident

   fish. In no case may D.O. be less than

   5 mg/l to a depth of 20 cm in the inter-

   stitial waters of gravel used by anadro-

   mous or resident fish for spawning

   (see note 2). For waters not used by

   anadromous or resident fish, D.O. must

   be greater than or equal to 5 mg/l. In no

   case may D.O. be greater than 17 mg/l.

   The concentration of total dissolved gas

   may not exceed 110% of saturation at

   any point of sample collection.

   Water Quality Standards for Designated Uses

   POLLUTANT & WATER USE CRITERIA (4) DISSOLVED INORGANIC

   SUBSTANCES, FOR

   FRESH WATER USES (A) Water supply

   all sources may not exceed 500

   mg/l. Neither chlorides nor sul-

   fates may exceed 250 mg/l.(A) Water Supply

   Sodium adsorption ratio must be less

   than 2.5, sodium percentage less than

   60%, and residual carbonate less than

   1.25 milliequivalents/liter (see note 6).(A) Water Supply

   concentration of TDS may not be pre-

   sent in water if that concentration

   causes or reasonably could be expected

   to cause an adverse effect to aquatic

   life (see note 12).(A) Water Supply

   that can cause corrosion, scaling, or

   process problems.(B) Water Recreation

   Water Quality Standards for Designated Uses

   POLLUTANT & WATER USE CRITERIA (5) PETROLEUM

   HYDROCARBONS, OILS

   AND GREASE, FOR

   FRESH WATER USES (A) Water supply

   the surface of the water. May not ex-

   ceed concentrations that individually

   or in combination impart odor or taste

   as determined by organoleptic tests.(A) Water Supply

   upon the surface of the water.(A) Water Supply

   in the water column may not exceed

   15 µg/l (see note 7). Total aromatic hy-

   drocarbons (TAH) in the water column

   may not exceed 10 µg/l (see note 7).

   There may be no concentrations of pet-

   roleum hydrocarbons, animal fats, or

   vegetable oils in shoreline or bottom sed-

   iments that cause deleterious effects to

   aquatic life. Surface waters and adjoin-

   ing shorelines must be virtually free

   from floating oil, film, sheen, or discolo-

   ration.(A) Water Supply

   or unsafe for the use.(B) Water Recreation

   coloration on the surface or floor of

   the water-body or adjoining shorelines.

   Surface waters must be virtually free

   from floating oils.(B) Water Recreation

   Water Quality Standards for Designated Uses

   POLLUTANT & WATER USE CRITERIA (6) pH, FOR FRESH WATER

   USES (variation of pH for

   waters naturally outside the

   specified range must be toward

   the range) (A) Water supply

   8.5. A) Water Supply

   9.0. A) Water Supply

   8.5. May not vary more than 0.5 pH unit

   from natural conditions.(A) Water Supply

   9.0. B) Water Recreation

   8.5. If the natural condition pH is outside

   this range, substances may not be added

   that cause an increase in the buffering ca-

   pacity of the water.(B) Water Recreation

   8.5. May not vary more than 0.5 pH unit

   from natural conditions.

   Water Quality Standards for Designated Uses

   POLLUTANT & WATER USE CRITERIA (7) RADIOACTIVITY, FOR

   FRESH WATER USES (A) Water supply

   cified in Table I of the Alaska Water

   Quality Criteria Manual (see note 5)

   for radioactive contaminants and may not

   exceed limits specified in 10 C.F.R. 20

   (see note 9) and National Bureau of

   Standards, Handbook 69 (see note 10).(A) Water Supply

   tion factors for organisms involved may

   not exceed maximum permissible limits

   for specific radioisotopes and unidentified

   mixtures as established by 10 C.F.R. 20

   (see note 9) and National Bureau of Stan-

   dards, Handbook 69 (see note 10).(A) Water Supply

   Water Quality Standards for Designated Uses

   POLLUTANT & WATER USE CRITERIA (8) RESIDUES, FOR FRESH

   WATER USES: Floating

   solids, debris, sludge,

   deposits, foam, scum, or

   other residues (criteria

   are not applicable to

   groundwater) (A) Water supply

   other substances or wastes, make the

   water unfit or unsafe for the use; cause

   a film, sheen, or discoloration on the sur-

   face of the water or adjoining shore-

   lines; cause leaching of toxic or delete-

   rious substances; or cause a sludge,

   solid or emulsion to be deposited beneath

   or upon the surface of the water, within

   the water column, on the bottom, or

   upon adjoining shorelines.(A) Water Supply

   cause soil plugging or reduced crop

   yield, or to make the water unfit or

   unsafe for the use; (A) Water Supply

   with other substances or wastes,

   make the water unfit or unsafe

   for the use; (A) Water Supply

   with other substances or wastes,

   make the water unfit or unsafe for

   the use, or cause acute or chronic

   problem levels as determined by

   bioassay or other appropriate meth-

   ods; may not, alone or in combina-

   tion with other substances, cause a

   film, sheen, or discoloration on the

   surface of the water or adjoining

   shorelines; cause leaching of toxic

   or deleterious substances; or cause

   a sludge, solid, or emulsion to be de-

   posited beneath or upon the surface

   of the water, within the water col-

   umn, on the bottom, or upon adjoin-

   ing shorelines.

   Water Quality Standards for Designated Uses

   POLLUTANT & WATER USE CRITERIA (9) SEDIMENT, FOR FRESH

   WATER USES (criteria are

   not applicable to

   groundwater) (A) Water supply

   tration of settleable solids above na-

   tural conditions, as measured by the

   volumetric Imhoff cone method (see

   note 11).(A) Water Supply

   free of particles of 0.074 mm or coar-

   ser. For irrigation or water spreading,

   may not exceed 200 mg/1 for an extend-

   ed period of time.(A) Water Supply

   with established water supply treat-

   ment levels.(A) Water Supply

   human contact or cause interference

   with the use.(C) Growth and Propagation of

   Fish, Shellfish, Other Aquatic

   Life, and WildlifeThe percent accumulation of fine sedi-

   ment in the range of 0.1 mm to 4.0 mm

   in the gravel bed of waters used by ana-

   dromous or resident fish for spawning

   may not be increased more than 5% by

   weight above natural conditions (as

   shown from grain size accumulation

   graph). In no case may the 0.1 mm to

   4.0 mm fine sediment range in those

   gravel beds exceed a maximum of 30%

   by weight (as shown from grain size

   accumulation graph) (see notes 3 and

   4). In all other surface waters no sedi-

   ment loads (suspended or deposited)

   that can cause adverse effects on

   aquatic animal or plant life, their re-

   production or habitat may be present.

   Water Quality Standards for Designated Uses

   POLLUTANT & WATER USE CRITERIA (10) TEMPERATURE, FOR

   FRESH WATER USES (A) Water supply

   The following maximum temperatures

   may not be exceeded, where applicable:

   Migration routes 15° C

   Spawning areas 13° C

   Rearing areas 15° C

   Egg & fry incubation 13° C

   For all other waters, the weekly average

   temperature may not exceed site-specific

   requirements needed to preserve normal

   species diversity or to prevent appearance

   of nuisance organisms.(A) Water Supply

   Water Quality Standards for Designated Uses

   POLLUTANT & WATER USE CRITERIA (11) TOXIC AND OTHER

   DELETERIOUS ORGANIC

   AND INORGANIC

   SUBSTANCES, FOR

   FRESH WATER USES (A) Water supply

   may not exceed the numeric criteria for

   drinking water and human health for con-

   sumption of water and aquatic organisms

   shown in the Alaska Water Quality Criter-

   ia Manual (see note 5). Substances may

   not be introduced at concentrations that

   cause, or can reasonably be expected to

   cause, either singly or in combination,

   odor, taste, or other adverse effects on

   the use.(A) Water Supply

   may not exceed the numeric criteria for

   drinking water and stockwater and irriga-

   tion water shown in the Alaska Water

   Quality Criteria Manual (see note 5). Sub-

   stances may not be introduced at concen-

   trations that cause, or can reasonably be

   expected to cause, either singly or in com-

   bination, odor, taste, or other adverse ef-

   fects on the use.(A) Water Supply

   hazards to worker contact may not be

   present.(B) Water Recreation

   may not exceed the numeric criteria for

   drinking water shown in the Alaska Water

   Quality Criteria Manual (see note 5). Sub-

   stances may not be introduced at concen-

   trations that cause, or can reasonably be

   expected to cause, either singly or in com-

   bination, odor, taste, or other adverse ef-

   fects on the use.(B) Water Recreation

   hazards to incidental human contact may

   not be present.(C) Growth and Propagation of

   Fish, Shellfish, Other Aquatic

   Life, and WildlifeThe concentration of substances in water

   may not exceed the numeric criteria for

   aquatic life for fresh water and human

   health for consumption of aquatic organ-

   isms only shown in the Alaska Water

   Quality Criteria Manual (see note 5), or

   any chronic and acute criteria established

   in this chapter, for a toxic pollutant of con-

   cern, to protect sensitive and biologically

   important life stages of resident species

   of this state. There may be no concentra-

   tions of toxic substances in water or in

   shoreline or bottom sediments, that, sin-

   gly or in combination, cause, or reason-

   ably can be expected to cause, adverse

   effects on aquatic life or produce unde-

   sirable or nuisance aquatic life, except

   as authorized by this chapter. Substances

   may not be present in concentrations that

   individually or in combination impart

   undesirable odor or taste to fish or

   other aquatic organisms, as determined

   by either bioassay or organoleptic tests.

   Water Quality Standards for Designated Uses

   POLLUTANT & WATER USE CRITERIA (12) TURBIDITY, FOR

   FRESH WATER USES

   (criteria are not

   applicable to

   groundwater) (A) Water supply

   units (NTU) above natural conditions

   when the natural turbidity is 50 NTU or

   less, and may not have more than 10%

   increase in turbidity when the natural

   turbidity is more than 50 NTU, not to

   exceed a maximum increase of 25 NTU.(A) Water Supply

   indicated use.(A) Water Supply

   conditions. For all lake waters, may not

   exceed 5 NTU above natural conditions.(A) Water Supply

   on established water supply treatment

   levels.(B) Water Recreation

   conditions when the natural turbidity is

   50 NTU or less, and may not have more

   than 10% increase in turbidity when the

   natural turbidity is more than 50 NTU,

   not to exceed a maximum increase of 15

   NTU. May not exceed 5 NTU above na-

   tural turbidity for all lake waters.(B) Water Recreation

   conditions when natural turbidity is 50

   NTU or less, and may not have more

   than 20% increase in turbidity when the

   natural turbidity is greater than 50 NTU,

   not to exceed a maximum increase of 15

   NTU. For all lake waters, turbidity may

   not exceed 5 NTU above natural turbidity.(C) Growth and Propagation of

   Fish, Shellfish, Other Aquatic

   Life, and WildlifeSame as (12)(A)(iii).

   Water Quality Standards for Designated Uses

   POLLUTANT & WATER USE CRITERIA (13) COLOR, FOR MARINE

   WATER USES (see note 8) (A) Water Supply

   natural condition, whichever is greater.(A) Water Supply

   natural condition, whichever is greater.(A) Water Supply

   stances that produce objectionable

   color.(C) Growth and Propagation of

   Fish, Shellfish, Other Aquatic

   Life, and WildlifeColor or apparent color may not reduce

   the depth of the compensation point for

   photosynthetic activity by more than

   10% from the seasonally established

   norm for aquatic life. For all waters

   without a seasonally established norm

   for aquatic life, color or apparent color

   may not exceed 50 color units or the na-

   tural condition, whichever is greater.(D) Harvesting for Consumption

   of Raw Mollusks or Other

   Raw Aquatic LifeSame as (13)(C).

   Water Quality Standards for Designated Uses

   POLLUTANT & WATER USE CRITERIA (14) BACTERIA, FOR

   MARINE WATER USES

   (see note 1) (A) Water Supply

   metric mean of samples taken in a 30-

   day period may not exceed 200 fecal

   coliform/100 ml, and not more than 10%

   of the samples may exceed 400 fecal

   coliform/100 ml. For products not normal-

   ly cooked, the geometric mean of samples

   taken in a 30-day period may not exceed

   20 fecal coliform/100 ml, and not more

   than 10% of the samples may exceed

   40 fecal coliform/100 ml.(A) Water Supply

   of samples may not exceed 20 fecal

   coliform/100 ml, and not more than 10%

   of the samples may exceed 40 fecal

   coliform/100 ml.(A) Water Supply

   geometric mean of samples taken in a

   30-day period may not exceed 200 fecal

   coliform/100 ml, and not more than 10%

   of the samples may exceed 400 fecal

   coliform/100 ml.(B) Water Recreation

   samples may not exceed 35 enterococci

   CFU/100 ml, and not more than 10%

   of the samples may exceed a statistical

   threshold value (STV) of 130 enterococci

   CFU/100 ml.(B) Water Recreation

   of samples may not exceed 200 fecal

   coliform/100 ml, and not more than 10%

   of the samples may exceed 400 fecal

   coliform/100 ml.(C) Growth and Propagation of

   Fish, Shellfish, Other Aquatic

   Life, and WildlifeNot applicable.(D) Harvesting for Consumption

   of Raw Mollusks or Other

   Raw Aquatic LifeThe geometic mean of samples may not

   exceed 14 fecal coliform/100 ml; and not

   more than 10% of the samples may exceed

   - 43 MPN per 100 ml for a five-tube

   decimal dilution test;

   - 49 MPN per 100 ml for a three-tube

   decimal dilution test;

   - 28 MPN per 100 ml for a twelve-tube

   single dilution test;

   - 31 CFU per 100 ml for a membrane

   filtration test (see note 14).

   Water Quality Standards for Designated Uses

   POLLUTANT & WATER USE CRITERIA (15) DISSOLVED GAS, FOR

   MARINE WATER USES (A) Water Supply

   tration in coastal water may not be less

   than 6.0 mg/l for a depth of one meter ex-

   cept when natural conditions cause this

   value to be depressed. D.O. may not be

   reduced below 4 mg/l at any point beneath

   the surface. D.O. concentrations in estu-

   aries and tidal tributaries may not be less

   than 5.0 mg/l except where natural condi-

   tions cause this value to be depressed. In

   no case may D.O. levels exceed 17 mg/l.

   The concentration of total dissolved gas

   may not exceed 110% of saturation at any

   point of sample collection.(A) Water Supply

   Water Quality Standards for Designated Uses

   POLLUTANT & WATER USE CRITERIA (16) DISSOLVED

   INORGANIC

   SUBSTANCES, FOR

   MARINE WATER USES (A) Water Supply

   cause a change in the water's isohaline

   patterns of more than 1-10% of the nat-

   ural variations.(A) Water Supply

   that can cause corrosion, scaling, or

   process problems.(B) Water Recreation

   ural salinity:

   Natural Human-Induced

   Salinity* Salinity*

   0.0 to 3.5 1

   Greater than 3.5 to 13.5 2

   Greater than 13.5 to 35.5 4

   *parts per thousand(D) Harvesting for Consumption

   of Raw Mollusks or Other

   Raw Aquatic LifeSame as (16)(A)(i) or (16)(C), which-

   ever is more stringent.

   Water Quality Standards for Designated Uses

   POLLUTANT & WATER USE CRITERIA (17) PETROLEUM

   HYDROCARBONS, OILS

   AND GREASE, FOR

   MARINE WATER USES (A) Water Supply

   the water column may not exceed 15 µg/l

   (see note 7). Total aromatic hydrocarbons

3. (TAH) in the water column may not ex- ceed 10 µg/l (see note 7). There may be no concentrations of petroleum hydrocar- bons, animal fats, or vegetable oils in shoreline or bottom sediments that cause deleterious effects to aquatic life. Surface waters and adjoining shorelines must be virtually free from floating oil, film, sheen, or discoloration.(A) Water Supply

   1. (ii) seafood processingMay not cause a film, sheen, or disco-
   2. (iii) industrialMay not make the water unfit or unsafe
   3. (i) contact recreationMay not cause a film, sheen, or disco-
   4. (ii) secondary recreationSame as (17)(B)(i).(C) Growth and Propagation of Fish, Shellfish, Other Aquatic Life, and WildlifeSame as (17)(A)(i).(D) Harvesting for Consumption of Raw Mollusks or Other Raw Aquatic LifeMay not exceed concentrations that
   5. (i) aquacultureMay not be less than 6.5 or greater than
   6. (ii) seafood processingMay not be less than 6.0 or greater than
   7. (iii) industrialMay not be less than 5.0 or greater than
   8. (i) contact recreationMay not be less than 6.0 or greater than
   9. (ii) secondary recreationSame as (18)(A)(iii).(C) Growth and Propagation of Fish, Shellfish, Other Aquatic Life, and WildlifeSame as (18)(A)(i).(D) Harvesting for Consumption of Raw Mollusks or Other Raw Aquatic LifeSame as (18)(A)(ii).
   10. (i) aquacultureMay not exceed the concentrations speci-
   11. (ii) seafood processingMay not exceed the concentrations speci-
   12. (iii) industrialSame as (19)(A)(ii).(B) Water Recreation
   13. (i) contact recreationSame as (19)(A)(ii).(B) Water Recreation
   14. (ii) secondary recreationSame as (19)(A)(ii).(C) Growth and Propagation of Fish, Shellfish, Other Aquatic Life, and WildlifeSame as (19)(A)(i).(D) Harvesting for Consumption of Raw Mollusks or Other Raw Aquatic LifeSame as (19)(A)(i).
   15. (i) aquacultureMay not, alone or in combination
   16. (ii) seafood processingMay not, alone or in combination with
   17. (iii) industrialMay not, alone or in combination with
   18. (i) contact recreationSame as (20)(A)(ii).(B) Water Recreation
   19. (ii) secondary recreationSame as (20)(A)(ii).(C) Growth and Propagation of Fish, Shellfish, Other Aquatic Life, and WildlifeMay not, alone or in combination with
   20. (i) aquacultureNo imposed loads that will interfere
   21. (ii) seafood processingBelow normally detectable amounts.(A) Water Supply
   22. (iii) industrialSame as (21)(A)(i).(B) Water Recreation
   23. (i) contact recreationNo measurable increase in concentra-
   24. (ii) secondary recreationMay not pose hazards to incidental
   25. (i) aquacultureMay not cause the weekly average temp-
   26. (ii) seafood processingMay not exceed 15° C.(A) Water Supply
   27. (iii) industrialMay not exceed 25° C.(B) Water Recreation
   28. (i) contact recreationNot applicable.(B) Water Recreation
   29. (ii) secondary recreationNot applicable.(C) Growth and Propagation of Fish, Shellfish, Other Aquatic Life, and WildlifeSame as (22)(A)(i).(D) Harvesting for Consumption of Raw Mollusks or Other Raw Aquatic LifeSame as (22)(A)(i).
   30. (i) aquacultureSame as (23)(C).(A) Water Supply
   31. (ii) seafood processingThe concentration of substances in water
   32. (iii) industrialConcentrations of substances that pose
   33. (i) contact recreationThere may be no concentrations of sub-
   34. (ii) secondary recreationConcentrations of substances that pose
   35. (i) aquacultureMay not exceed 25 nephelometric
   36. (ii) seafood processingMay not interfere with disinfection.(A) Water Supply
   37. (iii) industrialMay not cause detrimental effects
   38. (i) contact recreationSame as (24)(A)(i).(B) Water Recreation
   39. (ii) secondary recreationSame as (24)(A)(i).(C) Growth and Propagation of Fish, Shellfish, Other Aquatic Life, and WildlifeMay not reduce the depth of the

   loration on the surface or floor of the

   waterbody or adjoining shorelines. Sur-

   face waters must be virtually free from

   floating oils. May not exceed concen-

   trations that individually or in combi-

   nation impart odor or taste as determin-

   ed by organoleptic tests.(A) Water Supply

   for the use.(B) Water Recreation

   loration on the surface or floor of the

   waterbody or adjoining shorelines. Sur-

   face waters must be virtually free from

   floating oils.(B) Water Recreation

   individually or in combination impart

   undesirable odor or taste to organisms

   as determined by bioassay or organ-

   oleptic tests.

   Water Quality Standards for Designated Uses

   POLLUTANT & WATER USE CRITERIA (18) pH, FOR MARINE

   WATER USES (variation of

   pH for waters naturally

   outside the specified range

   must be toward the range) (A) Water Supply

   8.5, and may not vary more than 0.2 pH

   unit outside of the naturally occurring

   range.(A) Water Supply

   8.5. A) Water Supply

   9.0. B) Water Recreation

   8.5. If the natural pH condition is outside

   this range, substances may not be added

   that cause any increase in buffering cap-

   acity of the water.(B) Water Recreation

   Water Quality Standards for Designated Uses

   POLLUTANT & WATER USE CRITERIA (19) RADIOACTIVITY, FOR

   MARINE WATER USES (A) Water Supply

   fied in Table I of the Alaska Water Quality

   Criteria Manual (see note 5) for radioac-

   tive contaminants. Concentration factors

   for organisms involved may not exceed

   maximum permissible limits for specific

   radioisotopes and unidentified mixtures

   as established in 10 C.F.R. 20 (see note

   9) and National Bureau of Standards,

   Handbook 69 (see note 10).(A) Water Supply

   fied in Table I of the Alaska Water Quality

   Criteria Manual (see note 5) for radioac-

   tive contaminants and may not exceed

   limits specified in 10 C.F.R. 20 (see note

   9) or National Bureau of Standards,

   Handbook 69 (see note 10).(A) Water Supply

   Water Quality Standards for Designated Uses

   POLLUTANT & WATER USE CRITERIA (20) RESIDUES, FOR

   MARINE WATER USES:

   Floating solids, debris,

   sludge, deposits, foam,

   scum, or other residues (A) Water Supply

   with other substances or wastes,

   make the water unfit or unsafe for

   the use; may not detrimentally af-

   fect established water supply treat-

   ment levels.(A) Water Supply

   other substances or wastes, make the

   water unfit or unsafe for the use; cause

   a film, sheen, or discoloration on the sur-

   face of the water or adjoining shorelines;

   cause leaching of toxic or deleterious

   substances; or cause a sludge, solid, or

   emulsion to be deposited beneath or up-

   on the surface of the water, within the

   water column, on the bottom, or upon

   adjoining shorelines.(A) Water Supply

   other substances or wastes. make the

   water unfit or unsafe for the use.(B) Water Recreation

   other substances or wastes, make the

   water unfit or unsafe for the use, or

   cause acute or chronic problem levels

   as determined by bioassay or other ap-

   propriate methods; may not, alone or in

   combination with other substances,

   cause a film, sheen, or discoloration on

   the surface of the water or adjoining

   shorelines; cause leaching of toxic or

   deleterious substances; or cause a

   sludge, solid, or emulsion to be deposit-

   ed beneath or upon the surface of the

   water, within the water column, on the

   bottom, or upon adjoining shorelines.(D) Harvesting for Consumption

   of Raw Mollusks or Other

   Raw Aquatic LifeMay not, alone or in combination with

   other substances or wastes, make the

   water unfit or unsafe for the use; cause

   a film, sheen, or discoloration on the sur-

   face of the water or adjoining shorelines;

   cause leaching of toxic or deleterious

   substances; or cause a sludge, solid, or

   emulsion to be deposited beneath or up-

   on the surface of the water, within the

   water column, on the bottom, or upon

   adjoining shorelines.

   Water Quality Standards for Designated Uses

   POLLUTANT & WATER USE CRITERIA (21) SEDIMENT, FOR

   MARINE WATER USES (A) Water Supply

   with established water supply treat-

   ment levels.(A) Water Supply

   tion of settleable solids above natural

   conditions, as measured by the volu-

   metric Imhoff cone method (see note

   11).(B) Water Recreation

   human contact or cause interference

   with the use.(C) Growth and Propagation of

   Fish, Shellfish, Other Aquatic

   Life, and WildlifeSame as (21)(B)(i).(D) Harvesting for Consumption

   of Raw Mollusks or Other

   Raw Aquatic LifeNot applicable.

   Water Quality Standards for Designated Uses

   POLLUTANT & WATER USE CRITERIA (22) TEMPERATURE, FOR

   MARINE WATER USES (A) Water Supply

   erature to increase more than 1° C. The

   maximum rate of change may not exceed

   0.5° C per hour. Normal daily tempera-

   ture cycles may not be altered in ampli-

   tude or frequency.(A) Water Supply

   Water Quality Standards for Designated Uses

   POLLUTANT & WATER USE CRITERIA (23) TOXIC AND OTHER

   DELETERIOUS ORGANIC

   AND INORGANIC

   SUBSTANCES, FOR

   MARINE WATER USES (A) Water Supply

   may not exceed the numeric criteria for

   aquatic life for marine water shown in the

   Alaska Water Quality Criteria Manual

   (see note 5). Substances may not be intro-

   duced at concentrations that cause, or can

   reasonably be expected to cause, either

   singly or in combination, odor, taste, or

   other adverse effects on the use.(A) Water Supply

   hazards to worker contact may not be

   present.(B) Water Recreation

   stances in water, that alone or in combi-

   nation with other substances, make the

   water unfit or unsafe for the use.(B) Water Recreation

   hazards to incidental human contact may

   not be present.(C) Growth and Propagation of

   Fish, Shellfish, Other Aquatic

   Life, and WildlifeThe concentration of substances in

   water may not exceed the numeric

   criteria for aquatic life for marine

   water and human health for con-

   sumption of aquatic organisms

   only shown in the Alaska Water

   Quality Criteria Manual (see note

   5), or any chronic and acute criter-

   ia established in this chapter, for a

   toxic pollutant of concern, to protect

   sensitive and biologically important

   life stages of resident species of this

   state. There may be no concentra-

   tions of toxic substances in water

   or in shoreline or bottom sedi-

   ments, that, singly or in combination,

   cause, or reasonably can be expect-

   ed to cause, adverse effects on a-

   quatic life or produce undesirable

   or nuisance aquatic life, except as

   authorized by this chapter. Substan-

   ces may not be present in concen-

   trations that individually or in

   combination impart undesirable

   odor or taste to fish or other aqua-

   tic organisms, as determin-

   ed by either bioassay or organo-

   leptic tests.(D) Harvesting for Consumption

   of Raw Mollusks or Other

   Raw Aquatic LifeSame as (23)(C).

   Water Quality Standards for Designated Uses

   POLLUTANT & WATER USE CRITERIA (24) TURBIDITY, FOR

   MARINE WATER USES (A) Water Supply

   turbidity units (NTU).(A) Water Supply

   on established levels of water supply

   treatment.(B) Water Recreation

   compensation point for photosynthetic

   activity by more than 10%. May not

   reduce the maximum secchi disk depth

   by more than 10%.(D) Harvesting for Consumption

   of Raw Mollusks or Other

   Raw Aquatic LifeSame as (24)(C).

   Notes: 1. Wherever bacteria criteria are provided in this section, bacteria enumeration must be determined by the membrane filter technique or most probable number procedure according to any edition of Standard Methods for the Examination of Water and Wastewater, adopted by reference in (c)(1) of this section, or in accordance with other standards approved by the department and the United States Environmental Protection Agency (EPA). Bacteria results reported as "too numerous to count" (TNTC) is considered an exceedance for comparison to water quality standards. Analysis and reporting of the method recommended dilution of the sample is required. 2. Wherever criteria for dissolved oxygen (DO) are provided in this chapter, dissolved oxygen (DO) concentrations in interstitial waters of gravel beds will be measured using the technique found in Variations in the Dissolved Oxygen Content of Intragravel Water in Four Spawning Streams of Southeastern Alaska, by William J. McNeil, United States Department of the Interior, United States Fish and Wildlife Service, Special Scientific Report - Fisheries No. 402, February 1962, adopted by reference. 3. Wherever criteria for fine sediments are provided in this chapter, fine sediments must be sampled by the method described in An Improved Technique for Freeze Sampling Streambed Sediments, by William J. Walkotten, United States Department of Agriculture, United States Forest Service, Forest Service Research Note PNW-281, October 1976, adopted by reference, or by the technique found in Success of Pink Salmon Spawning Relative to Size of Spawning Bed Materials, by William J. McNeil and W.H. Ahnell, United States Department of the Interior, United States Fish and Wildlife Service, Special Scientific Report - Fisheries No. 469, January 1964, pages 1 - 3, adopted by reference. 4. Wherever criteria for fine sediments are provided in this chapter, percent accumulation of fine sediments will be measured by the technique found in the Manual on Test Sieving Methods, Guidelines for Establishing Sieve Analysis Procedures, by the American Society for Testing and Materials (ASTM), STP 447A, 1972 edition, adopted by reference. 5. Wherever cited in this subsection, the Alaska Water Quality Criteria Manual means the Alaska Water Quality Criteria for Toxic and Other Deleterious Organic and Inorganic Substances, dated April 1, 2026, adopted by reference in this subsection. 6. The Report of the Committee on Water Quality Criteria, United States Department of the Interior, Federal Water Pollution Control Administration, Washington, D.C., April 1, 1968, is adopted by reference. 7. Samples to determine concentrations of total aromatic hydrocarbons (TAH) and total aqueous hydrocarbons (TAqH) must be collected in marine and fresh waters below the surface and away from any observable sheen; concentrations of TAqH must be determined and summed using a combination of: (A) EPA Method 602 (plus xylenes) or EPA Method 624 to quantify monoaromatic hydrocarbons and to measure TAH; and (B) EPA Method 610 or EPA Method 625 to quantify polynuclear aromatic hydrocarbons listed in EPA Method 610; use of an alternative method requires department approval; the EPA methods referred to in this note may be found in Appendix A of 40 C.F.R. 136, as revised as of July 1, 2003 and adopted by reference. 8. Color is as measured in color units on the platinum-cobalt scale according to any edition of Standard Methods for the Examination of Water and Wastewater, adopted by reference. 9. Wherever cited in this chapter, 10 C.F.R. 20 means the Standards for Protection Against Radiation, revised as of January 1, 2014, and adopted by reference. 10. Wherever cited in this chapter, National Bureau of Standards Handbook 69 means Maximum Permissible Body Burdens and Maximum Permissible Concentrations of Radionuclides in Air and Water for Occupational Exposure, United States Department of Commerce, National Bureau of Standards Handbook 69, August 1963, adopted by reference. 11. Volumetric measurements of settleable solids must be determined according to the following procedure: (A) first, an Imhoff cone must be filled to the one-liter mark with thoroughly

   mixed sample; (B) second, the sample must settle for 45 minutes; (C) third, the sides of the cone must be gently stirred with a rod or by spinning; (D) fourth, the sample must settle 15 minutes longer, and the volume of settleable

   matter in the cone must be recorded as milliliters per liter; (E) fifth, if the settled matter contains pockets of liquid between large settled

   particles, the volume of these pockets must be estimated and subtracted from the

   volume of settled matter. 12. If a permit applicant proposes to raise the total dissolved solids (TDS) levels in the receiving water to result in a concentration in the waterbody between 500 mg/l and 1,000 mg/l for all sources or above 110 mg/l for the potassium ion, the department will require a permit applicant to provide information that the department identifies as necessary to determine if the proposed TDS level will cause or can reasonably be expected to cause an adverse effect to aquatic life; based on its analysis, the department will limit the TDS level in the waterbody as necessary to prevent an adverse effect, and will set permit effluent limits accordingly; the burden of proof to demonstrate no adverse effect is on the permit applicant; implementation of the ''no adverse effect'' criterion is not subject to 18 AAC 70.235. 13. repealed 11/13/2022. 14. When fecal coliform are monitored in waters designated as state approved shellfish harvesting and growing waters, these waters are also subject to 18 AAC 34.010(19).

4. (c) Water quality must be analyzed according to

   1. (1) Standard Methods for the Examination of Water and Wastewater, 22nd edition, 2012 or 23rd edition, 2017, published jointly by the American Public Health and American Water Works Associations and the Water Environment Federation; the editions of Standard Methods for the Examination of Water and Wastewater listed in this paragraph are adopted by reference, except for analytical methods where the most recently EPA approved version is required under (3) of this subsection and later versions of those methods are not adopted by reference and are not approved;
   2. (2) Methods for Chemical Analysis of Water and Wastes, March 1983, Environmental Monitoring and Support Laboratory, Office of Research and Development, United States Environmental Protection Agency, Technical Report No. EPA-600/4-79-020, adopted by reference;
   3. (3) 40 C.F.R. Part 136 (guidelines establishing test procedures for the analysis of pollutants), revised as of July 1, 2021, adopted by reference;
   4. (4) repealed 6/13/2006;
   5. (5) Methods for Organic Chemical Analysis of Municipal and Industrial Wastewater, July 1982, Environmental Monitoring and Support Laboratory, Office of Research and Development, United States Environmental Protection Agency, Technical Report No. EPA-600/4-82-057, adopted by reference;
   6. (6) methods cited in (b) of this section; or
   7. (7) other methods of analysis approved by the department and EPA.
5. (d) In applying acute aquatic life criteria, a one-hour averaging period typically is used for ammonia and other fast-acting toxic substances, a 24-hour averaging period is used for all other toxic substances, unless otherwise specified by the department.

(Eff. 11/1/97, Register 143; am 4/29/99, Register 150; am 5/27/99, Register 150; am 6/22/2003, Register 166; am 6/13/2006, Register 178; am 9/1/2006, Register 179; am 9/19/2009, Register 191; am 5/26/2011, Register 198; am 2/19/2016, Register 217; am 2/5/2017, Register 221; am 11/13/2022, Register 244; am 4/26/2024, Register 250)

Authority: AS 46.03.010, AS 46.03.050, AS 46.03.080, AS 46.03.020, AS 46.03.070, AS 46.03.710