Sodium levels are regularly monitored in water supplied to Peel’s consumers. Samples collected are analyzed at accredited and licensed laboratories and test results are compiled and made available to the public.
Although it is not considered toxic to people, sodium in drinking water in excess of 20 mg/L may be significant to individuals with hypertension or cardiovascular diseases. The Medical Officer of Health is notified when the sodium concentration in a municipal water supply exceeds 20 mg/L so the information can be provided to local physicians.
Water supplied to Mississauga, Brampton, Town of Bolton and areas of Caledon (north of Mayfield) is drawn from Lake Ontario. The lake water is relatively low in sodium with seasonal fluctuations that are mainly contributed to snow meltdown and run-off conditions. Sodium levels in Peel's surface water supplies are unlikely to be a significant contribution to adverse health effects.
Water supplied to Caledon communities is groundwater which may have elevated sodium concentrations in some areas. Sodium found in groundwater sources is naturally occurring. Several communal wells in Caledon provide water with a sodium concentration above 20 mg/L. Other sources of elevated sodium in drinking water may be water softening as household water softeners turn naturally occurring calcium and magnesium (“hardness”) to soft salts, such as sodium.
The following is the summary of sodium test results for sampling completed during 2018:
|Drinking Water System||Sodium
First Round 2018
(January to June)
Second Round 2018
(July to December)
(Mississauga, Brampton, South Caledon)