January 25, 2023
In 2020, the new Canadian Drinking Water Guideline for lead in drinking water was adopted in Manitoba. Due to the latest information about health effects from lower levels of lead exposure, the standard for total lead in drinking water was decreased from 0.01 mg/L to 0.005 mg/L.
The Office of Drinking Water (Manitoba Environment, Climate and Parks), in collaboration with Manitoba Public Health, is working with water systems to implement the new standard. Portage la Prairie was required to conduct random daytime (RDT) residential sampling for lead in 2022.
All water entering the City of Portage la Prairie distribution system from the water treatment plant meets the standard for lead and the total lead concentrations are often below the laboratory detection limit. The sources of lead in the water are usually related to lead service connections, lead solder in the plumbing of the home or lead plumbing fixtures. Therefore, testing at the tap in residential homes is the only way to determine if lead in drinking water is a concern.
The City was required to select 40 sample locations for lead water sampling. The City posted a request for volunteers and over 100 homeowners responded. Due to the overwhelming volume of applicants, the City focused mainly on homes likely to have lead water service lines. See the map of the area of homes prioritized for testing: Lead in Drinking Water Testing Program – City of Portage la Prairie (city-plap.com). 80% of the samples in 2022 were taken from homes on eight streets from either side of Tupper Street and two blocks north or south of Saskatchewan Avenue. The remainder of the samples were scattered across the City.
The following table summarizes the 42 sets of results:
|City of Portage la Prairie Lead Water Quality Test Results|
|Sample Type||Average (mg/L)||Minimum (mg/L)||Maximum (mg/L)||Number of samples||% of samples above guideline limit (0.005 mg/L)|
|5 Minute Flush||0.00147||0.00005||0.00500||42||0.00%|
While the City of Portage la Prairie has identified about 300 homes that have lead water service lines, it is not feasible to confirm every home’s water service. Individuals who are not sure what type of service is in their home should consult a certified plumber or contractor.
Manitoba Public Health has reviewed these findings and provides the following analysis and advice:
The findings from Portage la Prairie’s drinking water testing in residential homes show that over one quarter of the higher risk homes tested had lead in drinking water levels above the new guideline on a random daytime sample (RDT). However, after 5 minutes of flushing the water, all of the homes tested had lead in drinking water levels at or below the standard.
It is difficult to predict lead levels in homes since the plumbing can be different from house to house. Testing the lead levels in your water can help you make decisions on what actions are necessary. For information on having your water tested for lead please see: Lead in Drinking Water: Information for Manitoba Homeowners and Home-based Child Care Providers (gov.mb.ca) or you can volunteer for the City of Portage la Prairie testing program.
For more information on lead in drinking water, see Lead in Drinking Water: Information for Manitoba Homeowners and Home-based Child Care Providers (gov.mb.ca) and Quick Guide for Reducing Lead Exposure After Testing (gov.mb.ca).
The City has had a corrosion control program in place for over 15 years to help reduce lead in drinking water. The program is designed to improve the distributed water quality before it leaves the treatment plant, which helps reduce the transfer of lead into tap water.
The City would like to thank all of the residents who participated as well as those that applied but were not selected this year. The City is required to conduct this program annually and there will again be a call for volunteers in the spring of 2023 and the applications received in the spring of 2022 that were not chosen for sampling will be kept and added to the 2023 list.