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O. Reg. 169/03: ONTARIO DRINKING WATER QUALITY STANDARDS
under Safe Drinking Water Act, 2002, S.O. 2002, c. 32
Skip to contentSafe Drinking Water Act, 2002
ONTARIO drinking water quality standards
Consolidation Period: From January 1, 2020 to the e-Laws currency date.
Last amendment: 457/16.
Legislative History: 268/03, 17/04, 255/05, 248/06, 242/07, 327/08, 373/15, 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 |
0.01 |
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 |
35.1 |
Haloacetic acids |
0.08 (expressed as a running annual average of quarterly results) |
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; O. Reg. 457/16, s. 1.
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.