How do I test my home's water for lead?

Lead is a tasteless, odorless, colorless metal. Water carrying a harmful amount looks exactly like clean water, so your senses give you no warning. The EPA puts it plainly: "You cannot see, taste, or smell lead dissolved in water." A lab test is the only honest answer to whether your water is safe.

The federal action level for lead is 15 parts per billion (ppb). That is the threshold at which a water system must take corrective steps. It is not a line between safe and unsafe, because health agencies agree there is no known safe level of lead, especially for children. The newer Lead and Copper Rule Improvements (LCRI) lowers the action level to 10 ppb, with a compliance date of November 1, 2027, and requires lead service lines to be replaced within ten years.

It helps to know where the lead is coming from. Public water leaving a treatment plant is generally lead-free. The metal almost always enters from the home's own plumbing: lead pipes, a lead service line connecting the house to the main, brass fixtures, and solder used to join pipe. That is why two houses on the same street can have very different results, and why testing your specific tap matters more than reading the city report.

Your city's annual water quality report tells you what is in the water at the plant and in the distribution mains, but it cannot tell you what your own faucet delivers. The water that report describes may pick up lead in the last few feet of pipe inside your walls. A first-draw sample from your kitchen tap is the only measurement that reflects what you and your family actually drink, which is the whole reason home testing exists.

Federal law changed the plumbing supply chain in stages, and the dates tell you where the risk sits. Before 1986, plumbers commonly used solder that was roughly half lead to join copper pipe. Homes built or re-piped before that year are the highest-risk group.

The 1986 Safe Drinking Water Act amendments banned lead solder and lead pipe in systems for human consumption. A later update tightened the definition of lead-free to a weighted average of no more than 0.25% lead across the wetted surfaces of pipes and fixtures, the standard in force today. So "lead-free" brass made after that change still contains a trace amount, which is why flushing the tap still matters.

Phoenix homes span a wide range of ages, and the era a house was plumbed is a strong clue to its risk. A property built or re-piped well before 1986 is more likely to carry lead solder or older brass than a newer build. If you do not know your home's plumbing history, a licensed plumber can often tell from the visible pipe and fittings whether you have copper joined with lead solder, galvanized steel, or modern materials. Even so, the only way to confirm what reaches the glass is a water test.

Common culprits inside a home include:

• Lead service lines, the underground pipe from the street main to the house, the single largest source where present.
• Lead solder at copper pipe joints in homes plumbed before 1986.
• Brass fixtures and faucets, which can leach small amounts of lead even when sold as low-lead.
• Galvanized steel pipe, which can hold and later release lead particles, especially if it sat downstream of a lead line. See our guide on galvanized pipe problems for more on this.

Older, corroding pipes raise the risk because corrosion strips metal into the water. Our page on the signs of old, failing pipes covers what to watch for in an aging system.

A certified-lab test is straightforward. Follow the kit's instructions exactly, because the sampling method affects the result.

1. 1Order a kit from a certified lab. Contact a state-certified laboratory and request a lead drinking-water kit. It will arrive with a sample bottle and printed directions. Expect to pay $20 to $100.
2. 2Stop using water for at least 6 hours. Lead builds up while water sits still against the plumbing. Most labs want water that has been motionless for 6 hours or more, often overnight. Do not run any tap, flush a toilet, or run an appliance during that window.
3. 3Collect a first-draw sample. The next morning, before using any water, fill the bottle from the cold-water kitchen tap at the first flow, without letting it run first. This captures the water that sat in contact with your fixtures and pipes.
4. 4Label and seal the sample. Write the date, time, and tap location as the kit directs, then cap the bottle tightly.
5. 5Return it promptly. Mail or deliver the bottle to the lab within the timeframe on the instructions. Labs analyze the sample and report the result in parts per billion against the 15 ppb action level.

In Arizona, find a certified laboratory through the Arizona Department of Health Services (ADHS), which lists labs approved for drinking-water testing. Using a certified lab matters because its methods and equipment are checked for accuracy, and the result is documented in a form you can act on. At-home test strips are cheaper but far less reliable; they often miss low concentrations that still matter for a child, so treat a passing strip with caution and confirm anything worrying with a lab.

If you want a fuller picture, ask the lab whether it offers a combined panel that checks for lead alongside copper, since the two often travel together from the same brass and solder. A single first-draw sample is enough for a basic lead reading, but a lab can also describe a follow-up "flushed" sample, taken after the tap runs for a minute. Comparing the first-draw and flushed numbers helps pin down whether the lead is coming from your own fixtures or from a service line shared with the street.

You do not have to wait for results to lower your risk. A few habits cut exposure immediately and cost nothing.

• Use only cold water for drinking, cooking, and baby formula. Hot water dissolves lead faster, so never cook with or mix formula from the hot tap. Heat cold water on the stove if you need it warm.
• Flush the tap before use. If water has sat in the pipes for several hours, run the cold tap until it turns noticeably colder, often 30 seconds to 2 minutes, before drinking or cooking. Running a shower or a load of laundry first also clears the lines.
• Clean faucet aerators. Lead particles and debris collect in the small screen at the faucet tip. Remove and rinse it periodically.
• Replace old fixtures and plumbing. Swapping out pre-1986 fixtures, brass faucets, and lead-bearing pipe is the durable fix. A licensed plumber can identify and replace the at-risk parts.
• Consider a certified filter. A point-of-use filter rated for lead removal, such as a reverse-osmosis unit, treats water at the tap.

Lead is most dangerous for infants, young children, and pregnant women. In children it can harm brain and nervous-system development, lower IQ, and cause learning and behavior problems. In pregnancy it can reach the developing baby. Bottle-fed infants are a special concern because formula mixed with tap water may make up nearly all of what they drink.

If your test comes back above the action level, the CDC offers a clear instruction for households with young children or a pregnant person: "use bottled water or water from a filtration system that has been certified by an independent testing organization to reduce or eliminate lead for cooking, drinking, and baby formula." Switch to bottled or certified-filtered water for those uses until you have the source fixed and a re-test confirms the water is clean.

Beyond your own plumbing, knowing your overall water picture helps you weigh results in context. Our companion page on whether Phoenix tap water is safe to drink covers what the city tests for and how the municipal supply performs. Testing your tap, then acting on the number you get back, is the surest path from worry to a clear answer. If you need help locating a lead service line or replacing old fixtures, a licensed plumber can inspect your system and lay out your options.