Where should lead and copper samples be taken from?

Lead and copper samples should be taken from the customer's tap because this is where the water comes into contact with plumbing systems that may contain lead or copper. The U.S. Environmental Protection Agency (EPA) requires monitoring lead and copper levels specifically at the point of use to accurately assess the levels of these metals in the water that consumers actually receive.

Sampling at the customer's tap allows for a better understanding of potential contamination from leaching as water moves through plumbing materials, including pipes and fixtures, which can be sources of lead and copper. By focusing on this point, water utilities can gather essential data that reflects the actual exposure of consumers rather than conditions that might exist upstream in the treatment facility or source water, which may not represent the water quality at the delivery point.

Taking samples from the treatment facility, water source, or distribution reservoir does not provide a true reflection of lead and copper levels that customers experience, as those sites are not influenced by the residential plumbing systems. Therefore, the best practice is to collect samples directly from taps to effectively monitor and address lead and copper levels in drinking water.