Lead

We're in compliance with lead regulations (see our data here) and offer free lead testing upon request.

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

What keeps lead out of drinking water?
We reduce or prevent lead contamination by reducing the corrosiveness of our water and by adding orthophosphate during water treatment, which forms a thin protective coating inside pipes.

Lead Service Line - Orthophosphate Lining
The orthophosphate coating is visible inside this lead service line.

Is lead regulated?

What are the results of CWS lead testing?
Our most recent lead testing (August 2018*) included samples from 51 homes with lead service lines and/or plumbing components:

  • 33 homes - no lead detected
  • 17 homes - trace levels of lead detected; highest was 11 ppb
  • 90th percentile result was 2.3 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 only required to conduct lead sampling once every three years. Future sampling will occur in 2021, 2024, etc.

How do I know if I have a lead service line or plumbing?
Our water mains are not made of lead, but some service lines (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 pipe scratch test
Lead pipe scratch test. Lead appears bright silver when scratched with a coin.

If you're unsure if you have a lead service line, call us at (843) 727-6800 or email customerservice@charlestoncpw.com.

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

We'll replace our portion of a lead service line (between the water main and water meter) if we find it during field work or at a customer's request.

We do not replace the customers' portion of the service line (between the water meter and the home), as this is part of a customer's private plumbing.

How can I reduce my risk of lead exposure if I think I have lead plumbing?

  • Use cold water for cooking, drinking, and mixing infant formula. Lead is less likely to corrode into cold water.
  • If water sits in your pipes for an extended period of time, such as overnight, while you're at work, or when you're on vacation, flush your plumbing by letting cold water run for 3-5 min.
Will CWS test my water for lead?
Yes, we provide free lead testing upon request. Call (843) 727-6800 to get a test kit or visit one of our Customer Service locations.