Yelp rated
#1 Rated Denver Home Inspector
Call for a quote 303-730-7233 M-F 7AM-6PM | SAT 8AM - 5PM

Are unhealthy lead pipes lurking in your Denver home?

February 4, 2021

With all the controversy surrounding lead pipes in Flint, Michigan, municipalities around the country started to question whether lead pipes are a problem in their own hometowns. Here’s how to know in Denver whether the house you’re buying or occupying has lead pipes.

Which areas of Denver might have lead pipes? Any house built in 1951 or older could have lead pipes. So you’re only going to see these in the older parts of Denver and the inner suburbs. Denver Water estimates there are 64,000 to 84,000 homes in the Denver area that might have lead pipes. Those of you who live out in the newer suburbs, breathe a sigh of relief.

Why are lead pipes a concern? Microscopic pieces of lead can slough off the interior of the pipes and find their way into drinking water. Ingested lead is toxic to the human body, particularly in children where it can affect the brain and development. Lead pipes were outlawed decades ago.
I remember my dad used to run the water for a few seconds before taking a drink and I always wondered why. He was born in 1929, and I think he had been taught to clear the pipes of lead buildup before pouring himself a glass!

Which pipes in the house are we worried about? The pipes of concern are the water supply pipes. These are the ones that carry potable drinkable water to the kitchen and bath fixtures inside the house.

How to identify lead pipes. You’ll see lead supply piping in the basement ceiling or beneath the floor in the crawlspace. Lead water supply pipes will be roughly an inch in diameter and they are grey in color. Lead is a soft metal so if you scrape it with a knife-edge you can gouge it or shave a little off. Fittings that connect pipes together have a bulbous appearance with no threads.

Don’t confuse lead with galvanized steel. Lead is different that galvanized steel, which you’re much more likely to see because it’s a much more common material. Galvanized steel is harder, you won’t be able to scrape it, and the fittings are threaded. Galvanized pipes are not a health concern, but it’s an obsolete material that is prone to corrosion and leaking, particularly at the joints. If your house has a lot of galvanized piping it’s probably time for an upgrade to modern piping as well.

Supply pipes vs. drain pipes. Some old drain pipes are made of lead but these aren’t a concern because they carry waste water out of the house. Waste lines can be differentiated because they are much larger in diameter, roughly 2 inches to 4 inches across. Often you’ll see these under the floor at bathtubs, toilets, and kitchen sinks.

How common are lead water pipes in Denver? Two answers. 1. In my experience as a home inspector, lead supply pipes inside the house are rare, though we do see them occasionally on home inspections in Denver. Usually someone has identified them already and had them removed. 2. However, the underground service line sending the water from the city main to your individual house has a higher likelihood of being lead. The reason lead still might be present is that it’s buried pipe, so homeowners and their plumbers may not be aware of it. Also replacing a service line is costly so it’s less likely to have been done. Your only hope of visually identifying the pipe material is to find the short piece that enters the house upstream of the main house shutoff valve. This will be at the front of the house in the basement or in the crawlspace. But here’s the rub, often that short piece connecting the main house valve to the service line is not lead, but the pipe buried in the yard upstream of it is lead. You might have a lead service and not be able to see it. So, now what?

My home inspector will find it, right? Part of the home inspector’s professional standard of practice is to identify the service main material and the interior supply piping material. So we’re often able to catch it and report it. However, a home inspection is a visual exercise, the home inspector can only report what he or she can see. Pipes running under floors, through walls, or under the ground cannot be seen. Then how can a homeowner or homebuyer ensure safety for their family relative to lead pipes?

Enter Denver Water. Denver Water has a new lead pipe replacement program in place. Over the next 15 years, they will be systematically identifying and replacing lead service lines, at their expense. In the meanwhile, they may have sent you a pitcher-type water filter you can use for drinking water while you’re waiting for them to catch up to your house. I’ve seen these pitchers in several houses recently. If you want to know if your house has a lead service line, they have database mapping system where you can query your address. Link here. Note, this program does not cover piping inside the house. Indoor piping replacement is on the homeowner.

I have to wait 15 years to be safe? Not at all. If you don’t want to wait for what could be a decade or more for Denver Water to reach your house, you can have your service line replaced by your own plumber and Denver Water will partially reimburse you. The current rate is $3,800. Use water filtration systems in the meanwhile.

What should a Realtor tell homebuyers? First check the age of the house. If it was built after 1951, you’re in the clear. Second, ask your home inspector, he or she may be able to see lead piping in the house, but not in all cases and not for buried pipes. As a precaution, always search the Denver Water database for more information.

Questions? As always, if you have any questions don’t hesitate to reach out to me by responding to this post or emailing me at

Warm regards,

See also:
Denver Water lead main replacement program
Denver Post article




CALL FOR A QUOTE phone icon 303-730-7233
Yelp rated
#1 Rated Denver Home Inspector
Call for a quote 303-730-7233 M-F 7AM-6PM | SAT 8AM - 1PM