London water quality is monitored closely, but “safe” and “ideal” are not the same thing. Understanding what is in your pipes is the first step toward protecting your family.
I’m Aron Oretan, a Licensed Red Seal Plumber and Steamfitter with 26 years in the trade. I test water in London, St. Thomas, and Woodstock. Here is what I actually find.
Where London Water Quality Starts
According to the City, London’s water comes from Lake Huron and Lake Erie. Woodstock is different. It runs on groundwater wells.
Your source matters because it sets your starting point. Lake water and well water carry very different minerals.
Chlorine and Taste in London Water
Chlorine keeps the water safe on its way to your tap. The City monitors chlorine levels at 10 locations across London. It does its job.
The cost is taste and smell. Many of my customers describe a “swimming pool” taste. A carbon filter handles that. It won’t touch hardness minerals.
London Water Quality and Hardness
London water is hard enough to leave scale on your fixtures over time. The City’s 2025 water report measured hardness between 110 and 126 mg/L. That is roughly 6.5 to 7.5 grains per gallon.
Woodstock is much harder. Oxford County’s report says its wells tested between 324 and 693 mg/L in 2022. That is 19 to 41 grains per gallon.
Scale builds up on faucets, inside pipes, and in your water heater. Those minerals can slowly choke a heater and shorten its life. A water softener is the fix for hardness.
Old Pipes: Lead and Sediment
Water can leave the plant in good condition and still change on the way to your glass. That is more likely in an older neighbourhood.
The City of London says only copper or plastic service pipes were used in modern builds. It says there is little cause for concern if your house was built after 1952. If your home is older, you may have a lead service line.
The City owns the public side of that pipe. You own the private side. The City offers free lead testing of tap water for Londoners in older homes. It says the best way to reduce lead exposure is to replace the line.
Older pipes also collect grit. After a nearby water main repair, you may see discoloured water. That is sediment stirred up in the line. Run the cold tap until it clears.
Why One Filter Rarely Fits London Water Quality
I tell my customers there is no single best filter. There is only the right filter for your home.
A filter that removes chlorine taste might do nothing for hardness. Lead needs a filter certified for lead removal. Check the label. Hardness needs a softener.
Our water treatment and filtration page covers the options. Most homes end up with one or two pieces, not everything.
Want Me to Check Your London Water Quality?
If you’re curious about the hardness of your water, I’ll test it. For lead, use the City’s free testing first. Book online or call 226-270-5177. See our plumbing services for the rest of what we do.
Frequently Asked Questions
What is London water quality like?
The City treats and tests it and publishes annual water reports. Whether it’s ideal for your home depends on taste, hardness, and your pipes.
Is London water hard?
Yes, hard enough to leave scale. The City’s 2025 testing measured 110 to 126 mg/L, roughly 6.5 to 7.5 grains per gallon.
Is Woodstock water harder than London water?
Yes. Woodstock’s wells tested between 324 and 693 mg/L in 2022, which is 19 to 41 grains per gallon.
Does my London home have lead pipes?
Only older homes might. The City says there is little cause for concern if your home was built after 1952. It offers free lead testing for older homes.
Will a water filter remove lead and hardness?
It depends on the filter. Carbon filters remove chlorine taste. Hardness needs a softener, and lead needs a filter certified for lead.
Why does my tap water taste like a swimming pool?
That is chlorine. It keeps the water safe, and a carbon filter removes the taste.
Can hard water damage my water heater?
Yes. Minerals build up inside the tank and can shorten its life.
Hi, I’m Aron Oretan. With 25 years in the plumbing trade, I’ve seen the “history” of London’s pipes firsthand. I founded Triton Home Service to give our community honest, expert advice and high-quality water solutions. If you have questions about your water or just want a second opinion, I’m always happy to help.
Give me a call at 226-270-5177—let’s make sure your home’s water is at its best.