Lead and Copper Rule
The primary source of lead and copper in drinking water is copper pipes, lead solder used to join copper pipes, lead service lines and customer's residential plumbing and fixtures. Service lines are the pipes that carry water from the water main to the customer's meter (owned by the utility) and lines that carry water from the meter to the customers home (owned by the customer). The use of lead service lines and lead containing plumbing are typically found in older homes and historic residential areas. The use of lead service lines in public drinking water systems occurred well into the 1950s. Public water systems have some knowledge of where lead service lines have been used but the exact numbers of lines is not usually known. The Federal and State's lead and copper rule, under most circumstances, does not require removal of lead material. It requires adjustment of water chemistry and monitoring to insure metals leaching is not occurring.
The lead and copper rule establishes criteria for monitoring and treatment of public drinking water systems to protect public health. This rule establishes a treatment technique to address lead and copper levels. Instead of a maximum contaminant level, an action level is established which if exceeded requires a public water system to take actions to reduce corrosivity of water and reduce leaching of metals from plumbing into the water. The most common water treatments involve adjusting pH and alkalinity to reduce solubility and affect calcium deposition on pipes or the addition of phosphate products to provide a physical barrier between pipes and the water.
The lead and copper rule requires public water systems to collect customer tap samples from sites served by the system that are more likely to have plumbing materials containing lead. If more than 10 percent of tap water samples exceed the lead action level of 15 parts per billion, then water systems are required to take additional actions including:
- Taking further steps optimize their corrosion control treatment (for water systems serving 50,000 people that have not fully optimized their corrosion control).
- Educating the public about lead in drinking water and actions consumers can take to reduce their exposure to lead.
- Replacing the portions of lead service lines (lines that connect distribution mains to customers) under the water system's control.
To obtain information on lead levels found in your drinking water, contact TDEC or your local public water system provider. Follow the web links below to obtain additional information regarding lead in drinking water and steps you can take to reduce lead exposure from all sources.
Rules - Public Water Systems - 0400-45-01-.33 Control of Lead and Copper