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Safe Drinking Water Act, 2002

ONTARIO REGULATION 169/03

ONTARIO drinking water quality standards

Consolidation Period: From July 1, 2017 to the e-Laws currency date.

Last amendment: O. Reg. 457/16.

This is the English version of a bilingual regulation.

Standards

1. The standards set out in Schedules 1, 2 and 3 are prescribed as drinking water quality standards for the purposes of the Act.  O. Reg. 169/03, s. 1.

Deemed compliance

2. (1) A person who, pursuant to section 10 of the Act or otherwise, has an obligation to ensure that water meets a standard set out in Schedule 1, 2 or 3 shall be deemed not to have contravened the obligation if, in circumstances where the water does not meet the standard, the person immediately contacts the medical officer of health and takes such other steps as are directed by the medical officer of health.  O. Reg. 169/03, s. 2 (1).

(2) Despite subsection (1), the owner or operating authority of a drinking water system that provides water that does not meet a standard set out in Schedule 1, 2 or 3 shall be deemed not to have contravened paragraph 1 of subsection 11 (1) of the Act only if the owner or operating authority ensures that the appropriate corrective action is taken under Schedule 17 or 18 to Ontario Regulation 170/03 (Drinking Water Systems).  O. Reg. 169/03, s. 2 (2); O. Reg. 255/05, s. 1; O. Reg. 327/08, s. 1.

3. Omitted (provides for coming into force of provisions of the English version of this Regulation).  O. Reg. 169/03, s. 3.

SCHEDULE 1
MICROBIOLOGICAL STANDARDS

Item

Microbiological Parameter

Standard (expressed as a maximum)

1.

Escherichia coli (E. coli)

Not detectable

2.

Revoked:  O. Reg. 248/06, s. 1.

3.

Total coliforms

Not detectable

4.

Revoked:  O. Reg. 248/06, s. 1.

5.

Revoked:  O. Reg. 248/06, s. 1.

O. Reg. 169/03, Sched. 1; O. Reg. 248/06, s. 1.

Schedule 2
CHEMICAL STANDARDS

Item

Chemical Parameter

Standard (expressed as a maximum concentration in milligrams per litre)

1.

Alachlor

0.005

2.

Antimony

0.006

3.

Arsenic

0.025

4.

Atrazine + N-dealkylated metabolites

0.005

5.

Azinphos-methyl

0.02

6.

Barium

1.0

7.

Benzene

0.001

8.

Benzo(a)pyrene

0.00001

9.

Boron

5.0

10.

Bromate

0.01

11.

Bromoxynil

0.005

12.

Cadmium

0.005

13.

Carbaryl

0.09

14.

Carbofuran

0.09

15.

Carbon Tetrachloride

0.002

16.

Chloramines

3.0


16.1

Chlorate

1.0


16.2

Chlorite

1.0

17.

Chlorpyrifos

0.09

18.

Chromium

0.05

19.

Cyanide

0.2

20.

Diazinon

0.02

21.

Dicamba

0.12

22.

1,2-Dichlorobenzene

0.2

23.

1,4-Dichlorobenzene

0.005

24.

1,2-Dichloroethane

0.005

25.

1,1-Dichloroethylene (vinylidene chloride)

0.014

26.

Dichloromethane

0.05

27.

2,4-Dichlorophenol

0.9

28.

2,4-Dichlorophenoxy acetic acid (2,4-D)

0.1

29.

Diclofop-methyl

0.009

30.

Dimethoate

0.02

31.

Dioxin and Furan

0.000000015 (Total toxic equivalents when compared with 2,3,7,8-TCDD (tetrachlorodibenzo-p-dioxin))

32.

Diquat

0.07

33.

Diuron

0.15

33.1

Ethylbenzene

0.14

34.

Fluoride

1.5

35.

Glyphosate

0.28

36.

Lead

0.010

37.

Malathion

0.19

38.

Mercury

0.001


38.1

2-Methyl-4-chlorophenoxyacetic acid

0.1

39.

Metolachlor

0.05

40.

Metribuzin

0.08

41.

Microcystin LR

0.0015

42.

Monochlorobenzene

0.08

43.

Nitrate (as nitrogen)

10.0

44.

Nitrite (as nitrogen)

1.0

45.

Revoked: O. Reg. 457/16, s. 1 (4).

46.

Nitrilotriacetic Acid (NTA)

0.4

47.

N-Nitrosodimethylamine (NDMA)

0.000009

48.

Paraquat

0.01

49.

Pentachlorophenol

0.06

50.

Phorate

0.002

51.

Picloram

0.19

52.

Polychlorinated Biphenyls (PCB)

0.003

53.

Prometryne

0.001

54.

Selenium

0.05

55.

Simazine

0.01

56.

Terbufos

0.001

57.

Tetrachloroethylene (perchloroethylene)

0.01

58.

2,3,4,6-Tetrachlorophenol

0.1

58.1

Toluene

0.06

59.

Triallate

0.23

60.

Trichloroethylene

0.005

61.

2,4,6-Trichlorophenol

0.005

62.

Trifluralin

0.045

63.

Trihalomethanes

0.100 (expressed as a running annual average of quarterly results)

64.

Uranium

0.02

65.

Vinyl Chloride

0.001

66.

Xylenes

0.09

O. Reg. 373/15, s. 1 (1, 3-5, 7, 8); O. Reg. 457/16, s. 1.

Note: On January 1, 2018, Item 3 of Schedule 2 to the Regulation is amended by striking out “0.025” in Column 3 and substituting “0.01”. (See: O. Reg. 373/15, s. 1 (2))

Note: On January 1, 2020, Schedule 2 to the Regulation is amended by adding the following item: (See: O. Reg. 373/15, s. 1 (6))


35.1

Haloacetic acids

0.08 (expressed as a running annual average of quarterly results)

SCHEDULE 3
RADIOLOGICAL STANDARDS

Table 1
Natural Radionuclides

Item

Radiological Parameter

Standard (expressed as a maximum in becquerels per litre)

1.

Beryllium-7

4000.0

2.

Bismuth -210

70.0

3.

Lead-210

0.1

4.

Polonium-210

0.2

5.

Radium-224

2.0

6.

Radium-226

0.6

7.

Radium-228

0.5

8.

Thorium-228

2.0

9.

Thorium-230

0.4

10.

Thorium-232

0.1

11.

Thorium-234

20.0

12.

Uranium-234

4.0

13.

Uranium-235

4.0

14.

Uranium-238

4.0

Table 2
Artificial Radionuclides

Item

Radiological Parameter

Standard (expressed as a maximum in becquerels per litre)

1.

Americium-241

0.2

2.

Antimony-122

50.0

3.

Antimony-124

40.0

4.

Antimony-125

100.0

5.

Barium-140

40.0

6.

Bromine-82

300.0

7.

Calcium-45

200.0

8.

Calcium-47

60.0

9.

Carbon-14

200.0

10.

Cerium-141

100.0

11.

Cerium-144

20.0

12.

Cesium-131

2000.0

13.

Cesium-134

7.0

14.

Cesium-136

50.0

15.

Cesium-137

10.0

16.

Chromium-51

3000.0

17.

Cobalt-57

40.0

18.

Cobalt-58

20.0

19.

Cobalt-60

2.0

20.

Gallium-67

500.0

21.

Gold-198

90.0

22.

Indium-111

400.0

23.

Iodine-125

10.0

24.

Iodine-129

1.0

25.

Iodine-131

6.0

26.

Iron-55

300.0

27.

Iron-59

40.0

28.

Manganese-54

200.0

29.

Mercury-197

400.0

30.

Mercury-203

80.0

31.

Molybdenum-99

70.0

32.

Neptunium-239

100.0

33.

Niobium-95

200.0

34.

Phosphorus-32

50.0

35.

Plutonium-238

0.3

36.

Plutonium-239

0.2

37.

Plutonium-240

0.2

38.

Plutonium-241

10.0

39.

Rhodium-105

300.0

40.

Rubidium-81

3000.0

41.

Rubidium-86

50.0

42.

Ruthenium-103

100.0

43.

Ruthenium-106

10.0

44.

Selenium-75

70.0

45.

Silver-108m

70.0

46.

Silver-110m

50.0

47.

Silver-111

70.0

48.

Sodium-22

50.0

49.

Strontium-85

300.0

50.

Strontium-89

40.0

51.

Strontium-90

5.0

52.

Sulphur-35

500.0

53.

Technetium-99

200.0

54.

Technetium-99m

7000.0

55.

Tellurium-129m

40.0

56.

Tellurium-131m

40.0

57.

Tellurium-132

40.0

58.

Thallium-201

2000.0

59.

Tritium

7000.0

60.

Ytterbium-169

100.0

61.

Yttrium-90

30.0

62.

Yttrium-91

30.0

63.

Zinc-65

40.0

64.

Zirconium-95

100.0

Notes:

Radionuclide concentrations that exceed the standard may be tolerated for a short period, as long as the annual average concentrations remain below the standard and the restriction (see immediately below) for multiple radionuclides is met.

Restriction for multiple radionuclides:  Based on International Commission on Radiological Protection (ICRP) Publication 26, if two or more radionuclides are present, the sum of the quotients of the observed concentration in becquerels per litre divided by the respective standard in becquerels per litre for each of the radionuclides detected must be less than or equal to one.

O. Reg. 457/16, s. 2.

 

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