Lead is a soft, malleable metal that was used in everything from gasoline to plumbing materials before its health effects caused the federal government to limit its use beginning in the 1980s.

The lead crisis in Flint, Michigan has raised awareness of the potential risks of utility-owned lead service lines and lead plumbing components in customers' homes. 

Charleston Water System is in compliance with lead regulations and offers free lead testing at a customer's request. Below is more information about lead service lines, test results, and how CWS prevents lead from leaching into tap water.

How does lead get into drinking water?
Lead does not occur naturally in water. It comes from lead pipes or plumbing materials. Although the use of lead pipes and solder has been banned, homes built before 1986 may still have lead plumbing.

How does Charleston Water System keep lead from leaching into water?
We prevent lead contamination by reducing the corrosiveness of our water. Charleston Water System adds a compound called orthophosphate to water during the treatment process. This prevents corrosion by forming a thin protective coating inside pipes.

Lead Service Line - Orthophosphate Lining
The orthophosphate coating is visible inside this old lead service line. This coating prevents lead from leaching into tap water. 

Is lead regulated?
Yes, the US EPA regulates lead in drinking water through the Lead and Copper Rule. The rule requires utilities to test tap water from a sampling of homes that have lead service lines or plumbing. Lead levels must be below 15 parts per billion (ppb) for 90% of the samples tested--this is called the 90th percentile result.

If a utility exceeds that 15 ppb action level, then further action is required, including public notification/education.

Does CWS meet lead regulations?
Yes, our lead levels are well below the 15 ppb action level.
Read the history of CWS's compliance with the Lead and Copper Rule (PDF)

What are the results of CWS's lead testing?

The results of our most recent lead testing, which was conducted in August 2015 and included samples from 50 homes with lead service lines and/or plumbing components, are as follows:

  • 41 homes - no lead detected
  • 9 homes - trace levels of lead detected; highest was 3.1 ppb
  • 90th percentile result was 1.3 ppb, which is well below the 15 ppb action level

Because our lead levels have remained consistently low as a result of our corrosion control measures, we are required to conduct lead sampling once every three years. 

How do I know if I have a lead service line or plumbing?
Charleston Water System’s water mains are not made of lead, but some service lines (small pipes that carry water from our water mains to homes) and plumbing components are made of lead.  

Homes built before 1932 may have a lead service line, and those built before 1986 may have lead plumbing components.

Lead pipes have a dull gray appearance. The scratch test is an easy way to identify lead. Use a coin to scratch the pipe surface. If the scratch appears bright silver, it’s lead. 
Lead pipe scratch test
Lead pipe scratch test. Lead is a soft gray metal that appears bright silver when scratched with a coin.

If you're unsure whether you have a lead service line, contact us at 843-727-6800 or customerservice@charlestoncpw.com for more information.

To protect customers who have lead plumbing, we adjust the properties of our drinking water during the treatment process to prevent lead from corroding into the water. We test water samples from homes with lead plumbing to verify that our treatment is effective. Our most recent lead result is 1.3 parts per billion (ppb), which is well below the 15 ppb regulatory limit. 

If I have a lead service line, will you replace it?

Yes, we will replace our portion of a lead service line, which is located between the water main and the water meter, if we discover it during the course of field work or at a customer's request. 

We do not replace the customers' portion of the service line, which is located between the water meter and the home, as this is part of a customer's private plumbing system. Customers are responsible for replacing this section of their service line.

How can I reduce my risk of lead exposure if I think I have lead plumbing?
There are two things you can do to protect yourself from lead exposure:

  • Always use cold water for cooking, drinking, and mixing infant formula. Lead is less likely to corrode into cold water. 
  • If water has been sitting in your pipes for an extended period of time, such as overnight, while you're at work, or when you return from vacation, flush your plumbing by letting the cold water faucet run for 1 - 2 minutes before using the water for drinking or cooking. 
Will Charleston Water System test my water for lead?
Yes, we provide free lead testing upon request. If you think you have lead plumbing, call (843) 727-6800 to request a testing kit, or stop by one of our customer service locations.