Something as simple as your tap water may be costing you more than it should. You can’t always see its effects, but hard water (water that’s high in calcium and magnesium minerals) causes an unsightly and often damaging buildup on everything from sinks and tubs to pipes and water-using appliances. Texas, Arizona, Nevada, British Columbia and Ontario are among the states and provinces with the hardest water, but even moderately hard water can work against you.
Even outside of these hotspots, hard water is common in North America, and its costs to homeowners add up fast. According to water quality research and industry estimates from Culligan, switching from hard to soft water can save the typical North American household an average of $682 USD per year. That adds up to $13,654 USD over 20 years.
On average, Culligan data shows that, when using soft water instead of hard water:
- Gas tank water heaters consume 23% less energy, saving about $115 USD per month in energy costs.
- Tank water heaters have a 33% longer lifespan.
- Washing machines and dishwashers can last 50% longer.
Wondering how your region compares? This article from Culligan has the information you need. The following rankings show how water hardness varies across states and provinces.
Where is the hardest water in the U.S.?
USGS mapping shows the hardest water is generally concentrated in parts of the Southwest, Great Plains, and south-central U.S., while the Pacific Northwest and much of the Northeast tend to be softer. That said, it’s important to note that hardness can vary substantially within each state and even between neighboring communities.
A few factors increase the risk of water hardness:
- The presence of carbonate rocks rich in magnesium and calcium, such as limestone and dolomite
- Groundwater sourced from rocky aquifers rather than lakes or rivers
- A dry climate where there’s less precipitation to dilute mineral concentration
Water hardness is expressed as the concentration of calcium and magnesium ions in grains per gallon (gpg). The higher the mineral content, the harder the water:
- Soft: Less than 1.0 gpg
- Slightly Hard: 1.0-3.5 gpg
- Moderately Hard: 3.5-7.0 gpg
- Hard: 7.0-10.5 gpg
- Very Hard: More than 10.5 gpg
Ranking water hardness by state
The chart below ranks average hard water by state so you can see how yours compares. Keep in mind that water hardness varies significantly across regions within each state.
These are state averages synthesized from USGS, EPA SDWIS, and state environmental reports. Values represent population-weighted estimates; actual hardness varies significantly by city and water system. As the rankings show, hard water is common across the U.S., creating challenges for many homeowners.
Where is the hardest water in Canada?
In Canada, water hardness is determined by geology, water sources and climate, just as it is in the United States. The hardest water is typically in the Prairie provinces, where mineral-rich limestone and calcite increase groundwater hardness.
Ranking water hardness by province
The table below ranks each province by average water hardness. The presence of calcium and magnesium can vary greatly even within a province. For example, in British Columbia, Vancouver’s water is largely from mountain reservoirs, making it softer than groundwater sources in the interior.
Household cost of hard water
While water hardness rankings tell an interesting story, what matters most is the effects of hard water on your daily life.
When using hard water:
- Minerals build up inside water heaters and water-using appliances, reducing efficiency and leading to more frequent repairs and replacement. When shifting to soft water, you may save $1,301 USD on appliance replacement over a decade.
- The minerals leave a residue on your hair and skin. In one Culligan survey, more than 90% of respondents with a water softener said they saw a positive change in their hair and skin after using a water softener.
- You need more shampoo and detergent to create a lather. When switching from hard to soft water, most homes use 50% less dishwasher and laundry detergent, and 29% less soap and shampoo. This can translate to savings of $437 USD annually.
Homeowner awareness and next steps
If your state or province is among those with hard water, the best first step to manage its effects is to test your water. This gives you a precise picture of what’s going on in your home, as mineral content varies by community.
Routine maintenance, such as descaling appliances or cleaning faucets, can temporarily reduce buildup, but as long as there are minerals in the water, the problem will return. For a longer-term solution, consider a whole-house water softener that reduces the calcium and magnesium that cause hardness before they reach your pipes and appliances.
Understand your water’s hardness and protect your home
It’s easy to overlook the effects of hard water, but over time, household and maintenance costs will climb. The extent of your hard water problem depends on where you live, so water testing to determine the best solution is the most accurate way to determine your specific challenges.
This story was produced by Culligan and reviewed and distributed by Stacker.
