|LEAD IN DRINKING WATER WHAT’S BEEN DONE? THE PORTAGE LA PRAIRIE SITUATION|
As part of the City of Portage la Prairie’s ongoing drinking water review program and the continuing effort to ensure the City’s treated water meets current treatment standards, the City undertook testing of tap water at a few homes. Based on the test results of these few samples taken in September and November, 1999 and February, 2000, it has been determined that lead concentrations in tap water at homes with lead service connections is higher than the Canadian Drinking Water Guidelines maximum acceptable concentration (MAC) of 0.010 mg/l (10ppb), after extended periods of non-use.Lead is a common element found throughout the environment. The primary concern of health scientists related to low level exposure to lead is its potential impact on children, possibly resulting in small changes in intelligence, behavior and performance. Over the years lead levels can build up in the human body with continued exposure and this is considered unhealthy. Drinking water is a minor source of lead which contributes 5-10% of a person’s total lead intake. Major sources of lead include discharges to air which affect food, dust, and soil; lead based paints; and certain types of glazes used on porcelain and pottery.
|LEAD IN DRINKING WATER
Portage la Prairie’s raw water supply originates from the Assiniboine River which contains very low, nearly undetectable levels of lead. The treated water leaving the water treatment plant also has extremely low concentrations of lead. Lead dissolves into drinking water after it comes in contact with plumbing materials having lead in them. The longer the water stands in the plumbing system, the more lead that can dissolve into it.
Materials contributing to lead in water from water plumbing systems are: •Lead water service connections (pipes)
• Lead-based solder
• Brass faucets
|WHAT’S BEEN DONE?
Health Canada reduced the National Guideline for lead in drinking water from 30 to 10 parts per billion based on a flushed sample.The Province of Manitoba banned the use of lead solder for drinking water plumbing systems in 1989 and follows the new National Guideline.The City of Portage la Prairie has initiated testing and studies on lead in drinking water. Testing has continued to date to monitor for any changes in lead levels.As a result of the initial testing, the City notified Manitoba Health officials and began developing plans to deal with the issue of lead in water from lead service connections.
|THE PORTAGE LA PRAIRIE SITUATION|
|LEAD WATER CONDITIONS
Water connections are the pipes that carry water from watermains to individual residences. In the City of Portage la Prairie, there could be up to 1000 lead water connections in older parts of the city. This is about 15% of the total number of connections in the city. Your residence will likely not have a lead water connection if it was built in the 1950’s or later. You can check your service line on the incoming side of the water meter. Lead service lines are grey in color. Newer service lines are copper. If the line is painted, the paint can be removed with a knife. Scratched lead will appear silver in color.
|ACCEPTABLE LEAD LEVELS
Lead above 10 parts per billion is normally found in water which has been standing for some time in the plumbing system of homes with lead water service connections. Once the lines in a home and the service line have been flushed by opening a tap, the level of lead decreases significantly.
For the homes with lead water service connections, flushing for two to five minutes will lower the lead levels in drinking water but levels might remain above the maximum acceptable guideline limits of 10 parts per billion, especially during warmer months of the year.
|COPPER SERVICE LINES
From preliminary testing in Portage la Prairie, lead solder in copper water pipes does not appear to result in significant levels of lead in tap water. Flushing the system for a short period of about 30 seconds (4 to10 liters) after extended periods of non-use will reduce lead concentrations to very low levels, well within the Canadian Drinking Water Guidelines. If your home was constructed after 1989, it should not contain lead based solder. Lead in drinking water is not unique to Portage la Prairie. Many cities in North America and Manitoba, including Winnipeg, also experience lead in their drinking water.
Customers need not be unduly concerned about lead in their water, since precautions can be taken to minimize the risk. Manitoba Health Officials have been advised of the test results and have reviewed the Portage la Prairie situation regarding lead in drinking water and the potential effect on health. For most homes, average lead levels found in drinking water after letting the water run will not have adverse health effects. However, for those homes with lead water service connections, there may be some concern about the health effects on small children. The City and Manitoba Health advise consumers wishing to minimize lead intake to not drink tap water that has been standing in the plumbing system for a long time.
|TIPS TO REDUCE LEAD CONSUMPTION AND CONSERVE WATER
If you have a lead service connection, consider the use of a commercially available in-line or jug-type carbon filter for drinking water. When used properly, these filters will reduce lead concentration to acceptable levels.
|WHAT IS PORTAGE LA PRAIRIE DOING?
The City is continuing to investigate the various possible control measures for reducing lead in drinking water.
The City of Portage la Prairie currently monitors the “stability” of its treated water and makes treatment adjustments to minimize the corrosiveness, or tendency to dissolve lead into the water. However, due to the nature of the City’s water, it is slightly corrosive at certain times of the year.
|Another possibility to reduce lead is the replacement of the lead water service connection. If you have a lead water service connection, you may choose to have it replaced. The City is responsible for the water connection between the water main and the curb stop valve at the property line. The property owner is responsible for the water connection from that point to the house. If the City is making an excavated water pipe repair, the City will replace the lead connection for which it is responsible. You will be advised when this work is being done. You may save some money by having your portion of the connection replaced at the same time. To do this work, you must hire a plumbing contractor licensed by the City.Alternate chemical treatment strategies are being used to prevent the leaching of metals like lead, copper and other piping material. The City of Portage la Prairie is currently using a Phosphoric Acid to sequester the leaching of metals into the drinking water. Phosphoric Acid is being fed at an average of 1.84 ppm into the City of Portage la Prairie distribution system. The City also implemented a program to raise the pH of the water as it leaves the Water Treatment Plant. This helps to keep the water level from becoming acidic and thereby reduces the corrosivity of the water.Testing and monitoring of the phosphoric acid feed has been ongoing since the startup of the feed system in 2003. Since the start of the phosphoric acid addition, lead levels at homes with lead service lines has decreased.|
|The City of Portage la Prairie will continue to work with the Drinking Water Office to produce a safe drinking water for all|
|Lead Service Line Replacement Subsidy
To provide an incentive to property owners who wish to replace their lead water service lines, the City of Portage la Prairie offers a subsidy of $500 subject to the total budget allocated each year.