About Lead
All Public Water Systems (PWS) are required by both Federal and State law to test regularly for Lead in the system. In New Mexico, systems our size are required to submit 5 samples every 3 years. Had these tests shown a problem, we'd have to submit more samples, more often. Of the sites we last tested, 3 came back with trace levels, less than half the Maximum Contaminant Limit (MCL); the other 2 came back at zero/undetected. Of course the desirable amount is zero, and our system is PVC, so those probably indicate lead solder on the interior plumbing.
How does lead enter drinking water?
The water provided by your drinking water utility is lead-free. Lead enters drinking water when plumbing materials that contain lead corrode, especially where the water has high acidity or low mineral content that corrodes pipes and fixtures. The most common sources of lead in drinking water are lead pipes, faucets, and fixtures. In homes with lead pipes that connect the home to the water main, also known as lead services lines, these pipes are typically the most significant source of lead in the water.
Lead Service Lines
Water service lines are the underground pipes that connect home plumbing systems to public water mains. Water service lines can be made of plastic, copper, galvanized steel or iron, and lead, and metal pipes may use lead in soldered joints.
Lead Service Lines (LSLs) were installed in the US up until the 1960s, and while many have been replaced, there are still large numbers in use. There are limited records on water service lines on private property as many were installed decades ago and may have been tampered with or replaced since then. The only way to properly identify and inventory LSLs is with property-by-property assessing. The EPA has made the finding and replacement of LSLs a public health priority.
Because of its softness, Lead pipes were only made to about 2 inches in diameter. Far too small to be used in Water Mains, this size would be adequate for most small buildings and homes.
How to Identify a Lead Service Line
Step 1: Find your Point of Entry (POE)
Find the water service line entering your house as close as possible to the POE (close to where it comes through the foundation wall or slab). The incoming water service in your home may come up from the basement floor or out of a wall in the basement. If you have a crawlspace, it will come out of the floor. If your house is on a slab, it will come up through the main floor, typically in a utility closet.
- If the pipe looks plastic, obviously it isn’t Lead, but if it looks metallic, try scratching it. Use a key or coin to scratch the pipe close to where it enters the house through the wall or floor.
- What color is the pipe underneath?
- If it's silvery where you scratched, but dull/gray elsewhere, it's could be lead, especially if it was soft/easy to scratch, but test with a magnet to be sure. Like other serious contaminants, Lead is measured in Parts per Billion (PPB).
(If it was Lead, note how easy it was to scratch/dislodge some from the surface. [wash your hands after handling it] It could be dislodged by abrasives like sand, or a significant change in pH- which is what happened in Flint, Michigan when they changed water sources to the river; their old supply had built up a layer of calcium scale due to high pH/minerals present, but the river had much lower pH and stripped that protective shell off the City’s Lead Service Lines. A whole lot of people got very sick. After that incident, the EPA started planning a nationwide initiative to find and remove ALL Lead from plumbing in the United States.)
- If it looks like a penny, that’s Copper, one of the safest metals, but still one we monitor for in high levels (PPM- Parts per Million). The main reason the EPA keeps an eye on Copper though, is because Lead Solder was commonly used in Copper Plumbing, up until Lead was banned nationwide in 1986. (note: there’s a new substance hitting the EPA’s radar called PFAS, which for the first time will require testing in the PPT- Parts per Trillion and PPQ- Parts per Quadrillion ranges. Like Lead, they are hoping to eliminate PFAS entirely due to accumulation in the body.)
- Hold a magnet to your service line.
- If a magnet will stick, you have a steel service line. (There’s a small list of metals that are Ferromagnetic, e.g. a magnet will stick to: Iron, Nickel, Cobalt. Of these, only Iron & its alloys were used in plumbing. Galvanized Steel was very common, it’s coated with Zinc, and may require replacement if it was ever downstream of a Lead source such as old piping. Stainless Steel is coated with Nickel, a toxic metal that also must be monitored; it’s not typically seen in plumbing, but is often used in knives and cookware, to keep the surface shiny and new looking.)
- If a magnet won't stick, and it is not obviously plastic, you may have a lead service line. (Again, be sure to wash your hands after handling Lead. While some may absorb through the skin, you could expose yourself far more if you ingest it or rub your eyes.)
A licensed plumber can easily identify what type of material your service line is made of and assess your fittings for lead.
If you believe you have a lead service line or fittings, you should take action to reduce exposure and coordinate with your utility.
Talk to your water provider
Once you have determined what type of material your service line is made of, it is important to report that information to your water utility, even if it is not lead. Reach out to your utility and let them know that you have identified your pipe material.
This information will be used to determine the scale of the lead pipe issue in your community and may be used to determine funding for assistance programs to replace the lead lines. This information will be critical in determining how regulators, utilities, and customers can properly address the problem. Your utility may also know of potential sources of funding too assist with homeowner costs of lead service line replacements.
Take steps to reduce lead exposure
Here are some things you can do to reduce your exposure if you think your home’s plumbing may have lead.
- When water hasn’t been used for several hours, run all taps used for drinking and cooking. The flushing process could take from 30 seconds to 2 minutes or longer until it becomes cold or reaches a steady temperature. This will help flush old water and bring up fresh water from the water main. (The routine Lead Sampling required by NMED & the EPA require testing the 1st Liter, which looks at Lead in the house. 5th Liter testing rules this out and just looks at what’s coming in from the water system. So the rule of thumb is, if you want to clear out the old water from your plumbing, run about a gallon to flush it- you will probably feel a difference in temperature as the fresh water comes in, generally much colder- of course, if you have Lead, you probably don’t want to leave your hand in the flow to gauge that.)
- Never use hot tap water for drinking, cooking, or making baby formula. Hot water dissolves and carries lead more easily.
- Boiling water won’t remove lead and may even increase its concentration. The only way to remove lead from water is through filtering.
- Water filters: There are a wide variety of water filters on the market – from simple pour-through pitcher style filters to professionally installed plumbed-in filter systems. Some filters can reduce lead, but if you’re considering this route, be sure to choose one that is tested and certified, like the NSF standard 53. For more information on filters visit NSF.org – NSF International provides consumer information about water filter capabilities, including those that claim to reduce lead. The NSF can also be reached at 800-NSF-8010.
The US Environmental Protection Agency (EPA) Lead website contains information relating to all potential exposure routes for lead and what communities can do to address these issues.
EPA Protect Your Tap
The EPA's Protect Your Tap guide will help you determine if you have a lead service line bringing water into your home. It uses pictures, step-by-step directions to identify lead service lines, provides tips to reduce lead exposure, information on testing your water, and resources to learn more .
Centers for Disease Control and Prevention (CDC)
The CDC's Lead in Drinking Water resource page contains information about the risks of lead and steps that you should consider to help reduce exposure.
New Mexico Environment Department’s Drinking Water Bureau (NMED DWB)