| #Q001 | administrative | unknown | recommended | Consultation of Current Guidelines | drinking water | Health Canada updates this document regularly, but you should always consult individual guideline technical documents and guidance documents on the website Water Quality - Reports and Publications for the most current information. | When referring to water quality guidelines | high |
| #Q002 | monitoring | health | recommended | E. coli Monitoring Approach | drinking water | E. coli should be monitored in conjunction with other indicators, as part of a source-to-tap approach to producing drinking water of an acceptable quality. | Routine water quality verification | high |
| #Q003 | monitoring | operational | recommended | Total Coliforms Distribution Monitoring | drinking water | Total coliforms should be monitored in the distribution system because they are used to indicate changes in water quality. | Within the distribution system | high |
| #Q004 | monitoring | operational | recommended | Total Coliforms Treatment Plant Monitoring | drinking water | In water leaving a treatment plant, total coliforms should be measured in conjunction with other indicators to assess water quality; | Water leaving a treatment plant | high |
| #Q005 | corrective_action | health | recommended | Total Coliforms Detection Investigation | drinking water | Detection of total coliforms from consecutive samples from the same site or from more than 10% of the samples collected in a given sampling period should be investigated. | Consecutive samples from same site or >10% of samples in a period | high |
| #Q006 | administrative | operational | recommended | Turbidity Filtration Exemption | drinking water | The decision to exempt a waterworks from filtration should be made by the appropriate authority based on site-specific considerations, including historical and ongoing monitoring data. | Exemption from filtration | high |
| #Q007 | design | operational | recommended | Turbidity Operational Design | drinking water | Filtration systems should be designed and operated to reduce turbidity levels as low as reasonably achievable and strive to achieve a treated water turbidity target from individual filters of less than 0.1 NTU. | Filtration systems operation | high |
| #Q008 | corrective_action | operational | recommended | Membrane Unit Integrity Investigation | drinking water | Measurements greater than 0.1 NTU for a period greater than 15 minutes from an individual membrane unit should immediately trigger an investigation of the membrane unit integrity. | Turbidity > 0.1 NTU for > 15 minutes | high |
| #Q009 | operational | treatment | recommended | Chemical Reduction and Disinfection Efficacy | drinking water | Any measure taken to reduce concentrations of chemical substances should not compromise the effectiveness of disinfection. | When reducing chemical substance concentrations | high |
| #Q010 | monitoring | operational | mandatory | Aluminum Monitoring Location | drinking water | The MAC and OG apply to all drinking water supplies (including groundwater) and are to be applied as locational running annual averages. | Monitoring aluminum levels | high |
| #Q011 | monitoring | operational | recommended | Ammonia Monitoring requirement | drinking water | Levels of ammonia, either naturally present in the source water or added as part of a disinfection strategy, can affect water quality in the distribution system (e.g., nitrification) and should be monitored. | Presence of ammonia from source or disinfection | high |
| #Q012 | operational | health | recommended | Arsenic ALARA | drinking water | levels should be kept as low as reasonably achievable. | Arsenic presence in drinking water | high |
| #Q013 | prohibition | health | mandatory | Bromate Reduction and Disinfection Prohibition | drinking water | Efforts to reduce bromate concentrations must not compromise the effectiveness of disinfection. | When applying efforts to reduce bromate | high |
| #Q014 | operational | treatment | recommended | Bromate Strategy and Monitoring | drinking water | The recommended strategy is controlling the ozonation process; use of certified treatment chemicals and; appropriate handling and storage of hypochlorite. Quarterly monitoring of raw water bromide is recommended to allow correlation to bromate or brominated DBPs. | Managing bromate formation | high |
| #Q015 | monitoring | health | recommended | Cadmium Sampling Location | drinking water | Sampling should be done at the tap to reflect average exposure similar to sampling done for lead. | Monitoring cadmium levels | high |
| #Q016 | corrective_action | health | recommended | Cadmium Component Replacement | drinking water | The best approach to minimize exposure to cadmium from drinking water is to replace galvanized steel and components. | To minimize exposure to cadmium | high |
| #Q017 | operational | health | recommended | Chlorate Formation Control | drinking water | As chlorate is difficult to remove once formed, its formation should be controlled by respecting the maximum feed dose of 1.2 mg/L of chlorine dioxide and managing /monitoring formation in hypochlorite solutions. | Using chlorine dioxide or hypochlorite | high |
| #Q018 | prohibition | treatment | recommended | Chlorine Dioxide Dose Exceedance | drinking water | A maximum feed dose of 1.2 mg/L of chlorine dioxide should not be exceeded to control the formation of chlorite and chlorate. | Using chlorine dioxide | high |
| #Q019 | operational | health | recommended | Chlorite Formation Control | drinking water | Chlorite formation should be controlled by respecting the maximum feed dose of 1.2 mg/L of chlorine dioxide and managing /monitoring formation in hypochlorite solutions. | Using chlorine dioxide or hypochlorite | high |
| #Q020 | monitoring | health | recommended | Copper Tap Sampling | drinking water | Water samples should be taken at the tap. | Monitoring copper levels | high |
| #Q021 | corrective_action | health | recommended | Cyanobacterial Toxins Alternative Source | drinking water | As a precautionary measure, where levels of total microcystins in treated water are detected above a reference value of 0.4 µg/L, the public in the affected area should use an alternate suitable source of drinking water (such as bottled water) to reconstitute infant formula. | Total microcystins detected above 0.4 µg/L | high |
| #Q022 | operational | health | recommended | Dimethoate Additive Approach | drinking water | An additive approach should be taken in which the sum of the detected concentrations of dimethoate and omethoate (expressed as a dimethoate equivalent value) does not exceed the MAC for dimethoate. | When dimethoate and omethoate are present | high |
| #Q023 | design | treatment | mandatory | 1,4-Dioxane Treatment Consideration | drinking water | Treatment technologies such as advanced oxidation processes and synthetic adsorbents need to be considered. | Treatment of 1,4-Dioxane | high |
| #Q024 | design | health | recommended | Hardness Unsoftened Supply | drinking water | Where a water softener is used, a separate unsoftened supply for cooking and drinking purposes is recommended. | Where a water softener is used | high |
| #Q025 | monitoring | health | recommended | Lead ALARA and Sampling | drinking water | Lead levels should be kept as low as reasonably achievable. Sampling should be done at the tap to reflect average exposure. | Monitoring lead levels | high |
| #Q026 | corrective_action | health | recommended | Lead Service Line Removal | drinking water | The best approach to minimize exposure to lead from drinking water is to remove the full lead service line. | To minimize lead exposure | high |
| #Q027 | operational | treatment | recommended | Malathion By-products Awareness | drinking water | When using oxidation or advanced oxidation processes for malathion removal, water utilities should be aware of the potential for the formation of degradation by products. | Using oxidation/AOPs for malathion removal | high |
| #Q028 | monitoring | health | recommended | Nitrate Monitoring in Distribution | drinking water | Systems using chloramine disinfection or that have naturally occurring ammonia should monitor the level of nitrate in the distribution system. | Systems using chloramine or with naturally occurring ammonia | high |
| #Q029 | monitoring | health | recommended | Nitrate Well Testing | drinking water | Homeowners with a well should test concentration of nitrate in their water supply. | Homeowners with a well | high |
| #Q030 | monitoring | health | recommended | Nitrite Monitoring in Distribution | drinking water | Systems using chloramine disinfection or that have naturally occurring ammonia should monitor the level of nitrite in the distribution system. | Systems using chloramine or with naturally occurring ammonia | high |
| #Q031 | monitoring | health | recommended | Nitrite Well Testing | drinking water | Homeowners with a well should test concentration of nitrite in their water supply. | Homeowners with a well | high |
| #Q032 | operational | treatment | recommended | NDMA Formation Prevention | drinking water | Levels should be kept low by preventing formation during treatment. | During drinking water treatment | high |
| #Q033 | operational | health | recommended | PFAS ALARA Objective | drinking water | When treatment is required, it is also recommended that treatment plants strive to maintain PFAS concentrations in drinking water as low as reasonably achievable (ALARA). | When treatment for PFAS is required | high |
| #Q034 | design | health | recommended | Sodium Unsoftened Supply | drinking water | Where a sodium-based water softener is used, a separate unsoftened supply for cooking and drinking purposes is recommended. | Where a sodium-based water softener is used | high |
| #Q035 | operational | treatment | recommended | THMs ALARA and Precursor Removal | drinking water | Utilities should make every effort to maintain concentrations as low as reasonably achievable without compromising the effectiveness of disinfection. Recommended strategy is precursor removal. | Managing THM concentrations | high |
| #Q036 | operational | aesthetic | recommended | Zinc Plumbing Flushing | drinking water | plumbing should be thoroughly flushed before water is consumed. | Water with zinc levels above the AO | high |
| #Q037 | monitoring | health | recommended | Radiological Initial Screening | drinking water | Drinking water samples should initially be screened against a gross alpha radiation level of 0.5 Bq/L (becquerel/litre) and a gross beta level of 1 Bq/L. Individual radionuclide analysis is only necessary when one (or both) of these are exceeded. | Routine operational conditions | high |
| #Q038 | operational | health | recommended | Multiple Radionuclide Limit Ratio | drinking water | If more than one radionuclide in Table 1 is detected, the sum of the ratios of the observed concentration to their corresponding MAC should not exceed 1. | If more than one radionuclide is detected | high |
| #Q039 | corrective_action | health | recommended | Chloral Hydrate Investigation | drinking water | levels above 0.2 mg/L may indicate a concern for health effects and should be investigated. | Chloral hydrate > 0.2 mg/L | high |
| #Q040 | prohibition | health | recommended | Potassium Water Softener Avoidance | drinking water | those with kidney disease or other conditions, such as heart disease, coronary artery disease, hypertension or diabetes, and those who are taking medications that interfere with normal body potassium handling should avoid the consumption of water treated by water softeners using potassium chloride. | Individuals with kidney disease, heart disease, hypertension, diabetes, or taking certain medications | high |
| #Q041 | operational | operational | recommended | Nitrification Prevention - Ammonia Limitation | drinking water | To help prevent nitrification, limit excess free ammonia entering the distribution system to below 0.1 mg/L, and preferably below 0.05 mg/L, measured as nitrogen. | To prevent nitrification in systems with ammonia | high |
| #Q042 | monitoring | reporting | recommended | Dichlorobenzenes Isomer Analysis Requirement | drinking water | In cases where total dichlorobenzenes are measured and concentrations exceed the most stringent value (0.005 mg/L), the concentrations of the individual isomers should be established. | When total dichlorobenzenes exceed 0.005 mg/L | high |
| #Q043 | operational | treatment | recommended | Distribution Entry Turbidity Target | drinking water | To ensure effectiveness of disinfection and for good operation of the distribution system, it is recommended that water entering the distribution system have turbidity levels of 1.0 NTU or less. | Water entering the distribution system | high |
| #Q044 | operational | operational | recommended | Groundwater Turbidity Target | drinking water | For systems that use groundwater, turbidity should generally be below 1.0 NTU. | Drinking water systems using groundwater | high |
| #Q045 | monitoring | health | guidance | PFAS Isomer Concentration Examination | drinking water | If measurements of PFAS in drinking water are approaching or exceed the 30 ng/L objective, it may be useful to examine the types of PFAS that are present in the greatest concentrations. | Measurements approaching or exceeding 30 ng/L objective | high |
| #Q046 | administrative | health | recommended | Sodium Intake Recommendation for Restricted Diets | drinking water | For persons on strict sodium reduced diets applying to all sources, levels in drinking water should be below 20 mg/L | Persons on strict sodium reduced diets | high |
| #Q047 | monitoring | reporting | guidance | Disinfection By-product Monitoring Frequency | drinking water | Expressed as a locational running annual average of quarterly samples. | Applies to Haloacetic acids (HAAs) and Trihalomethanes (THMs) | high |