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Corrosion, Lead, and Copper in Home Water Supplies

Are You at Risk of These Three Common Problems
in Wisconsin's Drinking Water?

orrosion can occur when water reacts with metal plumbing.  Dissolved oxygen, low pH (acid water), and low mineral content in water are common causes of corrosion.  Corrosion can cause unsafe levels of lead and copper to dissolve into your drinking water.  It may also eventually cause leaky pipes, faucets, hot water heaters, or other plumbing fixtures.

ead  is a toxic metal once used in solder, pipes, and plumbing fixtures.  Lead solder (50/50 tin/lead) was used to join copper pipes until 1984 when it was banned in Wisconsin.  High lead levels in the body can damage many body organs and systems.  Lead can be especially dangerous to young children, infants, and the unborn.  A child's mental and physical development can be irreversibly affected by lead exposure.

Other risk factors for lead in drinking water include:

   Some faucets contain lead as a component of brass.

    Some public water supplies, even if they do not have lead service lines, may have lead service connections where the line to the home meets the water main in the street. 

   Submersible pumps in private wells may contribute small amounts of lead to water in their first month of operation.

    Some private water well screens (pre-1991) contain lead or a lead packing collar.
 
   "Shooting" the well with a gun to clear the drive point could contribute lead and is not recommended.

    Some parts of the "lead-zinc" mining region of southwestern Wisconsin have naturally occurring lead in groundwater.

    Some groundwater near existing or former cherry orchards in Door County may contain lead because of pesticide use.

Drinking water is not the only potential source of lead in the environment. Children may also be exposed to lead through lead-based paint, air, soil, household dust, food, and certain types of pottery, porcelain, and pewter.

The water sampled must have been in contact with the part of the plumbing suspected of causing the problem. 

Timing of the sampling is very important:

    If you suspect lead solder, lead water pipes, faucets, or the groundwater  to be the source of a lead problem; or if you are uncertain about possible lead sources, the testing should be done on a "first-draw" sample--one taken from a drinking water faucet after water has not been run for six hours or more. This collection method is used by the U.S. Environmental Protection Agency (EPA).

    If you suspect a new submersible pump, a lead service line or connection, lead in a well screen or packing collar, or "shooting" a well  to be the source of a lead problem, the water should not be run for six hours or more. Then, the cold water should be run until a change in temperature is noted. The sample should then be taken.

The U.S. Environmental Protection Agency (EPA) has established an action level of .015 milligrams per liter (mg/L) for lead in drinking water. Above this level, public water supplies are required to find ways to reduce lead levels in drinking water.

If testing shows lead in your water sample, take a second test. If your first test was a "first-draw" sample, the second test should be taken after flushing the cold water line until the water is as cold as it will get (usually 2-3 minutes). If your first test was on a flushed sample, collect your second sample two minutes after you first note a change in water temperature.

  opper is the metal commonly used to manufacture water pipes.  Too much copper in drinking water may cause vomiting, stomach cramps, diarrhea, and nausea.  Some cases of "formula intolerance" in infants may be caused by high copper levels in water.  Loss of copper from your pipes into the drinking water may also eventually cause leaks in the pipes.

Blue or green stains on porcelain fixtures indicate that significant corrosion problems exist and copper is being lost from your pipes.  Copper corroded from pipes may cause a metallic taste in drinking water. 

Infants and children are particularly sensitive to elevated copper levels in water.  The U.S. EPA has established an action level of 1.3 mg/L.  Long term exposure to high copper levels may cause kidney or liver damage in infants.

Testing should be performed on a "first-draw" sample.

olutions for corrosive water problems.  If you have a private well, you will need to have your water tested and the saturation index calculated (how corrosive it is). 

Options for preventing corrosion-related problems include:

    Replace metal pipes and fixtures with plastic.

    Flush your pipes before consuming the water to limit your exposure to lead and/or copper.

    Increase the hardness or alkalinity of the water with a water treatment device in the home, such as a neutralizer.

Water softening removes nearly all the calcium and magnesium from the water, so no scale buildup can occur.  When there is no scale formation, the metal plumbing may become more susceptible to the dissolving action of the water passing through it.