Why is testing for lead and copper in drinking water important?

To get water from the ground, to treatment, and into consumers’ homes, pipes are needed to move it along. A variety of materials have been used historically throughout the world. These include clay, metal, and plastic. Unfortunately, some materials leach chemicals into water that aren’t good for us. Lead and copper pipes are just two of these types. Both lead and copper, in certain quantities, can have negative health effects. Therefore, water systems monitor water quality for lead and copper to make sure it is safe to drink.

Every three years, the City of Tumwater is required to collect water samples from customers’ water taps for lead and copper testing by the Washington Department of Health (WADOH). The City of Tumwater was last sampled in 2022, while our satellite system, Lakeland Manor, was sampled in 2024. Sampling occurs during the summer, mainly August or September.

If you miss the tri-annual sampling or do not qualify for the City testing program, there is an alternative. Many certified labs in Washington perform these tests for $25 to $50 per test.

Where does lead and copper in drinking water come from?

Lead and copper occur naturally in our groundwater at very low levels. When water enters your home's plumbing system it may pick up a small amount of lead and copper from pipes and fixtures, especially in buildings constructed prior to 1987. The primary sources of lead and copper in drinking water are household plumbing and include the following:

• Copper pipe with lead solder
• Lead service lines
• Faucets
• Galvanized pipes

How can you reduce exposure?

If your home is older than 1987 or if you know that you have lead lines or fixtures in your home, you can reduce your exposure by doing the following:

• When your water has been sitting for several hours, flush the pipe by running the cold-water tap until the water is noticeably colder before using the water for drinking or cooking. The longer water has been sitting in the pipes, the more dissolved metals it may contain.
• Use only cold water for drinking, cooking, and making baby formula. Hot water may contain higher levels of lead or copper.
• Frequently clean the filter screens and aerators in faucets to remove captured particles.
• If building or remodeling, only use “lead free” or low lead piping and materials. Avoid using copper piping or brass fixtures for locations where water will be consumed or used in food preparation (such as kitchen or bathroom sinks).
• Consider using a water filter certified to remove lead and know when it’s time to replace the filter

Potential Health Effects of Lead

The greatest risk of lead exposure is to infants, young children, and pregnant women. Lead can cause serious health problems if too much enters the body. Lead is stored in the bones and can be released later in life. Lead can cause damage to the brain and kidneys, interfere with production of red blood cells that carry oxygen, and may result in lowered IQ in children. During pregnancy, the child receives lead from the mother’s bones, which may affect brain development. Low levels of lead can affect adults with high blood pressure or kidney problems.

Learn more about Lead in Drinking Water at the following State and Federal agencies websites:

• WA Department of Health: Lead in Drinking Water
• US EPA: Basic Information about Lead in Drinking Water

Potential Health Effects from Copper

Severe cases of copper poisoning have led to anemia and to the disruption of the liver and kidney functions. Individuals with Wilson and Menkes diseases (genetic disorders resulting in abnormal copper absorption and metabolism) are at higher risk from copper exposure than the general public and can have serious health problems.

Learn more about Copper in Drinking Water at the following website:

• WA Department of Health: Copper in Drinking Water

What have water quality results been in the past?

The US Environmental Protection Agency (US EPA) sets the action levels for lead and copper concentrations in drinking water. These levels are enforced by WADOH. If a water system exceeds these action levels at the 90^th percentile, new or additional treatments would be required to bring the levels of the contaminant below the action level.

US EPA Action Levels

The tables below show the last four rounds of lead and copper results for the City of Tumwater and Lakeland Manor systems.

City of Tumwater Lead and Copper Sampling Results

Lakeland Manor Lead and Copper Sampling Results

Definitions

Lead and Copper 90th Percentile:  Out of every ten homes samples, nine were at or below this level.

Action Level: The concentration of a contaminant which, if exceeded, triggers treatment or other requirements which a water system must follow. 

Contaminant:  Contaminants, as seen in this table, are not all "bad". Contaminants are anything found in your water other then hydrogen and oxygen, which make up water, and can be both healthy and unhealthy, depending on the particular substance and quantity. 

Maximum Contaminant Level Goal (MCLG): The highest level of a disinfectant allowed in drinking water. There is convincing evidence that addition of a disinfectant is necessary for control of microbial contaminants. 

mg/L: milligrams per liter

ppm: one part per million = 1 mg/L