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Exposure to lead can occur from various sources in our environment including but not limited to food, drinking water, air, household dust, soil, and some consumer products. In light of research correlating adverse health effects to lead exposure, there has been a substantial effort to reduce sources of lead exposure in our environment.
Lead in drinking water is currently an issue that is at the forefront of regulatory reviews and scientific research in both Canada and the United States. To that end, Halifax Water has developed a comprehensive policy to reduce exposure to lead in tap water with significant efforts being placed on getting the lead out of the distribution system.
What Are The Sources Of Lead In Drinking Water?
Drinking water is essentially lead-free in the distribution system and prior to entering your individual water service pipe. Lead can enter drinking water that travels through a lead service pipe or household plumbing containing lead solder or leaded brass through a process called corrosion. Lead service lines are restricted to the older parts of HRM such as the Halifax peninsula and central Dartmouth, in homes built in the 1950’s or earlier. Of the 80,000 service pipes within Halifax Water’s distribution systems, there are fewer than 2,500 lead lines in operation.
How Can I Identify A Lead Service Line Or Lead Plumbing?
You water service line is the pipe that enters your home through the wall or floor in your basement and is connected to your water meter. Service lines are typically composed of lead or copper. Lead service lines are characterized as a soft, non-magnetic metal that is silver/grey in color. Copper pipe, on the other hand, is bronze in color similar to a penny.
 
Lead Pipe Copper Pipe
Halifax Water maintains a database of public and private service line records. If you would like information regarding the public and private portions of your service line, please call 490-4098, or email us at lead@halifaxwater.ca.
What Are The Health Risks Associated With Lead Exposure?
Prolonged exposure to lead may put people at risk of developing certain adverse health effects. In particular, children below the age of six and pregnant women are most vulnerable. In children, it has been demonstrated that even low blood lead levels may reduce IQ, adversely affect cognitive development, and increase the risk of hyperactivity, behavioral problems, and impaired growth (USEPA, 2006). Lead ingestion by pregnant women can be harmful to a fetus and may result in lower birth weights and delayed mental and physical development.
Adults exposed to high levels of lead over a prolonged period of time may be subject to a wide range of adverse health effects. (USEPA, 2006).
For more information on the health effects of lead, visit Health Canada and the USEPA’s websites:
http://www.hc-sc.gc.ca/ewh-semt/pubs/water-eau/lead-plomb-eng.php
http://epa.gov/air/lead/health.html
What Is Halifax Water Doing To Minimize Lead In Tap Water?
Halifax Water has taken a pro-active approach to minimizing lead exposure from drinking water by adopting practices recommended in Health Canada’s Guidance on Controlling Corrosion in Drinking Water Distribution Systems (2009). These recommendations have been adopted and streamlined with Halifax Water’s current lead policy. The three main components of this policy include:
1. Corrosion Control Program
Corrosion of lead and other metals from pipes in the distribution system occurs from the reaction of water with metal surfaces. Halifax Water maintains an effective corrosion control program to minimize the corrosion of lead and other materials in the distribution system by using a corrosion inhibitor. Inhibitors work by producing a protective layer over pipes in the distribution system, which prevents the corrosive medium to from attacking the metal surface.
2. Residential Monitoring Program
Halifax Water voluntarily maintains a residential sampling program to monitor lead levels in customers’ homes throughout the distribution system. Once per year, as many as 100 households are tested for various metals, including lead. Under Health Canada’s guidelines, 90% of the samples must have a lead concentration of less than 15ug/L for a utility to consider their corrosion control program effective. In the past year, Halifax Water’s 90th percentile lead concentration was 9.94µg/L.
Halifax Water is currently seeking volunteer households for its upcoming sampling program scheduled for August 2013. Households supplied by Halifax Water are eligible to participate in the program. If you would like more information regarding this program or would like to participate, please call Trish Jodrey at (902)-490-4098.
3. Lead Service Line Replacement Program
To permanently address lead issues, Halifax Water has placed significant efforts in getting the lead out of the distribution system as this is the only way to permanently address sources of lead in drinking water. Currently, public lead service lines are proactively replaced in conjunction with street or paving projects and water main infrastructure upgrades. The complete removal of lead from the distribution system, however, requires the joint efforts of Halifax Water and the customer. To learn more about our Lead Service Line Replacement Program, please visit our website
Replacing the Public Section of a Lead Pipe with a Copper Pipe
What Can I Do To Minimize My Exposure To Lead?
The only way to permanently address lead exposure concerns is to remove all sources of lead in your home. The most common source of lead in drinking water in Halifax is lead pipes. Replacing the public and private portion of your lead service line will greatly reduce your exposure. Until such time as the public and private lead service pipes have been replaced, you can reduce or minimize your exposure to lead from drinking water by:
1. Draw cold tap water for cooking and drinking. Hot tap water can cause a greater release of lead from plumbing.
2. If water is not used for more than six hours (i.e., overnight, during work hours), flush the cold water tap for approximately five minutes prior to drinking and cooking. Flushing can also be achieved by running appliances such as your dishwasher, washing machine etc, or flushing the toilet.…
3. Periodically, remove and clean all faucet aerators.
4. If you are pregnant, breastfeeding or have children under the age of six, consider using a household water filter As per Health Canada’s recommendation, make sure that the filtration device is certified to NSF 53 International Standards for the removal of lead.
5. Boiling water will NOT remove lead!
If your house is connected by a lead service line and/or you have concerns about the quality of your water, please contact Halifax Water at (902) 490-4098, or by email at lead@halifaxwater.ca
Understanding Your Lead Test Results
Water samples are taken and analyzed for total lead concentration following a minimum 6 hour stagnation period. This stagnation period provides the “worst case” scenario and will generate the highest lead concentrations expected in the course of a day. Five liters of water are needed for the analysis; the first four liters are taken consecutively while the last liter is taken only after the water has been running for 5 minutes. The fifth liter, called the flush sample, is water taken from the distribution main which is essentially “lead-free”.
High lead concentrations in the first liter can sometimes point to a build-up of lead particles in the faucet aerator, particularly when there is no source of lead in the premise plumbing. This can be addressed by cleaning aerators regularly.
High lead concentrations in the second, third and fourth liters point to lead sources in the premise plumbing and/or service lines. Removal of all sources of lead is the only way to ensure your drinking water is lead-free.
High lead concentrations in the “flush” liter occurs very rarely and typically points to an error in sample collection. While 5 minutes is usually a sufficient amount of time for flushing, homes with long service lines may need to flush their lines longer to ensure they are drawing fresh water from the distribution main.
It is important to note that the concentration of lead in drinking water will fluctuate with temperature, flow and pipe age. Halifax Water’s corrosion control program helps to minimize corrosion of lead and other metals from piping. The only way to guarantee that your drinking water is “lead-free” is to remove all sources of lead in your premise plumbing and service lines.
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