Lead and Copper Rule

Lead in Drinking Water

  • Please Visit: SD Water Pipes as part of a nationwide initiative, water systems are asking people to look at their pipes and report their results, regardless of what they find. Knowing where lead lines are is just as important as knowing where they are not.

  • The most common sources of lead in drinking water are lead pipes, faucets and fixtures.
  • Lead pipes are more likely to be found in older cities and homes built before 1986.
  • You can't smell or taste lead in drinking water.
  • The only way to know for certain if you have lead in your drinking water is to have your water tested.
  • Remember that older homes with a private well can also have lead in drinking water.

Steps You Can Take to Reduce Lead in Drinking Water

  • Call your water company to learn about the lead levels in your system's drinking water.
  • Use only cold water for drinking, cooking and making baby formula.
  • Remember, boiling water does not remove lead from water.
  • Run water for 30 seconds to 2 minutes before drinking it, especially if you have not used your water for a few hours.
  • Regularly clean your faucet's screen (also known as an aerator).
  • If you use a filter certified to remove lead, don't forget to read the directions to learn when to change the cartridge. Using a filter after it has expired can make it less effective at removing lead.
  • Determine if the pipe that connects your home to the water main (e.g. service line) is made from lead by contacting your water company.
  • You can find out who your water company is by looking at your latest water bill.

Spread the Word!

Download materials and find out how you can participate in National Lead Poisoning Prevention Week

For more information


Corrective Actions


Corrective Actions

Yes, all community and non-transient non-community public water supplies are required to test for lead and copper according to the following schedule.

Sampling Requirements

Samples must always be taken at the designated and approved sites. The chosen sampling sites for lead and copper differ from the sites chosen for bacteriological sampling. Sampling sites for lead and copper are chosen by the age of the houses and the type of plumbing connected to the system. The sites chosen are often sites with the highest risk of lead and copper contamination. A site may have higher risk of contamination if there are lead service lines, copper plumbing, or lead solder. A list of the sites for each system is available from the Drinking Water Program should there be any question.

Samples are first-draw tap water samples taken in one liter bottles. These samples must be taken to a state approved lab. Samples must be collected from the kitchen or bathroom cold water tap. Lead and copper samples have a 14 day time frame between the time the samples are drawn and when they need to be preserved at the lab. Generally, homeowners may take the samples themselves rather than the operator.

Frequency of Sampling

Initially, samples must be taken for 2 consecutive six-month periods for one year. The six-month periods are from January 1 to June 30 and July 1 to Dec 31. If the 90th percentile levels of both sets of samples are one half of the action level or below, the monitoring may be reduced to samples every 3 years. If the 90th percentile levels of the past samples are below the action level but above one half of the action level, the sampling frequency may be reduced to annual.

If the 90th percentile does not exceed the action level for two consecutive annual monitoring periods, sampling frequency may be reduced to once every three years.

How to compute the 90th percentile

  • List the results from the lead and copper samples taken during a six-month period, numbering them in ascending order from lowest, being 1, to highest. The number assigned to the sample with the highest concentration must be equal to the total number of samples taken.
  • Multiply the total number of samples taken by 0.9 For example, if there are 20 samples, 20 x 0.9 = 18
  • The number that results from step 2 is the concentration in the 90th percentile used for comparison to the action level.
  • For water systems serving fewer than 100 people that collect only five water samples, the 90th percentile is measured by the average of the highest and the second highest concentrations.

Note: this computation can also be easily done by a representative in the Drinking Water Program and is in no way required to be complete upon submission of results.

System population Number of Sampling Sites
Initial Monitoring Reduced Monitoring
>100,000 100 50
10,001 to 100,000 60 30
3,301 to 10,000 40 20
501 to 3,300 20 10
101 to 500 10 5
<=100 5 5

Action Levels, Health Effects and Sources

The Lead Action Level is 0.015 mg/L. Adverse health effects of elevated lead levels for children include: altered physical and mental development; interference with growth; deficits in IQ, attention span and hearing; and interference with blood synthesis. In adults, the adverse health effects of elevated lead levels can increase blood pressure and shorten the gestational period.

The Copper Action Level is 1.3 mg/L. Adverse health effects of elevated copper levels include: Stomach and intestinal distress and Wilsons disease.

Elevated lead and copper levels in drinking water are usually caused by corrosion of interior household pipes and fixtures (i.e. lead solder, lead or copper pipes and brass faucets).

If your test results are higher than the action levels listed above your water system must:

  • Notify the Drinking Water Program and complete the public notices as required.
  • Work with the state agency to determining the best way to reduce the level of contaminate in your water supply.
  • Begin water quality parameter monitoring.
  • Explore treatments to reduce corrosion rates.
  • Complete public education, as required.

If your test results are higher than the action levels listed above your water system must:

More information on Lead contamination can be found in SD state pamphlet "Lead and your Drinking Water" and EPA's WEB page addressing Basic Information About Your Drinking Water.