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What is pH in Water?


When you measure the pH level of a substance like tap water, you’re determining how acidic or basic the water is. This level is based on the relative amount of hydrogen and hydroxyl ions in the substance. More hydrogen translates into a low pH level and is considered acidic, while more hydroxyl causes a high pH and is called basic or alkaline.

But what is pH in water and does it impact your home’s water quality? Here’s what to know.

pH Levels in Tap Water

The pH scale ranges from 0 to 14. Substances that are neither acidic nor basic, like pure water, are neutral and have a pH level of 7. However, that’s not the case for most real-world examples, because everything from nearby geological structures to ongoing human activities can impact pH. Even your own body has a pH level, which is partly why many people want to know the chemical composition of their water and what that might mean for health.

What Is High pH in Water?

Water with a high pH level (above 7) is basic or alkaline. Although experts say alkaline water isn’t necessarily better for you, some people still prefer it. They use alkaline water filters to control pH levels depending on their tastes.

You might guess a natural area has seriously high pH levels if it also has these things:

  • Dairy or coal pile runoff
  • Draining from naturally inundated wetlands or floodplains
  • Liquid industrial waste
  • Power plants

Depending on your location, these factors may have some impact on your home’s water quality. However, most of the time, the things impacting your tap and drinking water pH are much more commonplace — such as rocks and natural minerals.

What is Low pH in Water?

If water has a pH level below 7, it’s considered acidic. The world’s most acidic water was once found in a mine in California, showing a pH value of -0.7.

Although scientific measurements are the best ways to determine pH, you might be able to guess that a particular body of water has highly acidic water if these things are nearby:

  • Industrial landfills
  • Cement or soap manufacturing
  • Limestone gravel roads
  • Agricultural lime
  • Pine or fir forests

Fortunately, most sources of tap water are generally not directly exposed to these extremes. Other factors still impact the acidity, though — and particularly low levels can cause metals to leach from your home plumbing and get into your water. That’s part of the reason a more neutral pH level is generally ideal.

What is Ideal pH in Water?

The U.S. Environmental Protection Agency recommends a pH value between 6.5 and 9 for drinking water. The Guidelines for Canadian Drinking Water Quality establish a slightly higher range of 7 to 10.5. Your ideal tap water pH value will depend on your location, preferences and needs.

pH Water Testing

Some people may prefer certain pH levels; for example, if you like bottled mineral water, you’re enjoying higher pH. However, pH value can have further implications:

  • Acidic water might cause a metallic, sour taste and blue-green household stains.
  • Alkaline water could make beverages bitter and might lead to scale buildup.

Do you have water problems like these?
Try our Water Solutions Finder tool.

That’s why it’s important to learn your drinking water’s pH. To do that, you’ll need to have a professional pH water test. While there are plenty of DIY options available, a water expert can give you information — not to mention speed, accuracy and support — you won’t find anywhere else. That’s especially important when it comes to pH because this measurement can potentially indicate other issues. On top of that, pH also impacts chemical and biological processes in water and can interact with any other contaminants that may be present.*

Once your water test results are available — which should take around 30 minutes — your local water expert can recommend the next steps. Many pH problems are best solved by a whole-house water filtration system such as the Culligan® Smart High Efficiency Water Filter.

Find Your Water’s pH Level

You don’t have to be a scientist to learn about the chemistry behind your drinking water and how that impacts its taste, quality and more. Skip the DIY test strips and have a water expert tell you everything you need to know about pH. You’ll also learn about water hardness, chlorine, iron and other potential issues.

It all begins with a free, in-home water test and consultation. Schedule yours today.

*Contaminants may not be present in your water.

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