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What Is "Hard Water" and Is It Safe to Drink?

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RedElf (Elle Fredine) is a photographer, published author, and educator. Life-long learning is key to adding value to life.

Hard Water vs. Soft Water

As a child, I remember hearing my mother complain about the water being too hard. I don't remember which town we were in at the time, but "hard water" meant we needed to use more laundry soap and more dish detergent, and my mother spent more time cleaning calcium deposits off the tub and taps. I wasn't terribly concerned about hard water—after all, we could still drink it, wash in it, and swim in it, so I wondered why there was a problem.

Then, we moved to another town in a different province and were introduced to "soft water." The water tasted a bit odd, but that wasn't the biggest problem. It seemed that no matter how much we drank, we were still thirsty, even if we drank 'til our stomachs felt bloated. It took a while for our systems to acclimate, but our mother was thrilled with how little laundry soap, dish detergent, and shampoo we had to use.

What Is Hard Water and Is It Safe?

So what exactly is hard water? What makes water hard or soft?

Hard water is said to be hard because of a high concentration of minerals in the water, most commonly dissolved compounds of calcium and magnesium, either as carbonates or sulphates. Water hardness is measured by how many parts per million (ppm) of the minerals are dissolved in the water.

Though there is no single international standard by which hardness is measured, water hardness classifications set out by the U.S. Geological Surveys are generally accepted.

Soft water has a high sodium content. It's wonderful for doing dishes, laundry and bathing, but though your iron and dishwasher may thank you, your body won't. Even in low concentrations, sodium makes it hard to quench your thirst as you are drinking, in effect, "salty" water. In fact, the salt (sodium) in the water will increase your thirst the more you drink.

Is Hard Water Safe?

Hard water is not bad for you. You can drink it, bathe in it. Cook with it. If you are not used to drinking hard water—for example, if you have recently moved to an area with hard water from an area where you had softer water—you might experience some digestive upsets until your body gets used to the new water.

Water Hardness Classifications

ClassificationParts Per Million or Milligrams Per Liter

Soft Water

Less than 17.1

Slightly Hard

17.1 - 60

Moderately Hard

60 - 120


120 - 180

Very Hard

Over 180

What Produces Hard Water?

Hard water can be either temporary or permanent.

Temporary hardness in water is often caused by the presence of dissolved carbonate minerals (calcium carbonate and magnesium carbonate) leaching into the aquifer (water-bearing strata).

This “temporary” hardness can be reduced either by boiling the water, or by the addition of lime (calcium hydroxide). Boiling hard water precipitates the calcium carbonate out of solution, leaving water that is softer when it cools.

Permanent hardness is usually caused by the presence of calcium and magnesium sulphates and/or chlorides in the water. These become more soluble as the temperature increases, and cannot be removed by boiling. Despite its name though, permanent hardness can be removed.

Both kinds of hardness, temporary and permanent, can be removed by installing a water softener, which will usually filter out most of the minerals suspended in the water.

What Is Hard Water Scale?

In your own home, hard water can be a nuisance but it is generally not a serious problem. It can cause water scale in your sinks and bathtubs, and unsightly rings in your plant saucers. Very hard water can also clog your pipes and prevent your dishwasher from operating at full efficiency.

How to Remove Hard Water Scale

There are many commercially available products to descale taps and filers. The commercials on the television made it look so easy, but, believe me, it's not. It can take a long time, a lot of swishing, and use up a lot of product before your surfaces are "miraculously" clean of scale and stains.

Now I stick to a simple home remedy. It's natural, costs pennies a cup, and doesn't harm the environment. You can remove hard water scale with a simple application of vinegar. I soak my glass, china, or plastic plant saucers and pot-bottoms in a solution of vinegar and warm water, then give them a gentle scrub. Sometimes you will need to let things soak a bit longer. In that case, you can put several articles in the kitchen sink and let them sit for a while in the warm vinegar-water solution before scrubbing.

This method also works well for tap collars and bathroom fixtures, but go gently with the scrubbing so you don't mar the finish on your taps.

We always throw in about a cup of vinegar into the dishwasher for the last rinse. This not only super-cleans and degreases your glassware, dishes and cutlery, it leaves your dishwasher's interior sparkling.

You can also add up to a full cup of vinegar to your washing machine's rinse cycle. Be careful not to add more though, as you don't want your clothes or bedding to smell like pickles. That actually happened to me once when my son was much younger, and I added a bit too much vinegar to a load of diapers. It didn't hurt him at all, but we did get a few funny looks at the grocery store. Needless to say, I did extra laundry that week.

Do I Need to Use More Soap?

If your water is very hard, you will notice, as did my mother, that you need to use more laundry soap, detergent, and shampoo. That is because the minerals in the water inhibit the soap from foaming or creating lather—the higher the mineral content, the harder the water, and the more soap you will need to use to make soap suds.

My newer washing machine requires He (High energy) detergent, which is very effective in hard water, without creating too many soapsuds.

Does Hard Water Stain Clothes?

Sometimes, hard well water contains iron bacteria, which causes rust-colored staining along with the hard water scale. The bacteria can be removed by "shocking" the well with bleach, and is best done by a professional, or by adding an iron filter to your water softener. If you have iron bacteria in your water, I highly recommend using an iron filter, because the staining is made worse by hot water, and will permanently stain your clothes and linens, to say nothing of the mess it will make in your dishwasher.

Do I Need a Water Softener?

Installing a water softener in your home can be costly, so unless you are having serious problems with iron bacteria, you might not want to install a water softener.

In commercial applications, hard water can present a real problem. Hard water deposits (off-white scale) can clog plumbing. It can be deposited on the surfaces of pipes and heat exchangers, restricting the flow of water and compromising the efficiency of the heat exchanger, and in some cases, causing corrosion. Mineral deposits can also cause metal boiler components to overheat, and can cause the boiler to fail.

Installing and maintaining a water softener as part of industrial water treatment strategies will usually alleviate the problem, though in extreme cases, soft or distilled water may have to be piped in or trucked to the site.

Is Hard Water Safe to Drink?

Most towns and cities in North America and Europe have water treatment plants. As long as your water comes from a treatment plant, it should be safe to drink. Groundwater from a well or cistern should be regularly tested, but unless the mineral content exceeds safety standards, and there are no other contaminants, your water is safe for drinking.

I can personally vouch for the safety of hard drinking water; in fact, I prefer hard water over soft for drinking. I also prefer soft water for laundry and bathing. This can be problematic, as most households only have access to one water supply—from the local town or city, from their well or cistern, or, in some parts of Northern Alberta, from a dugout (a man-made, open-air cistern).

In fact, hard water is better for drinking than soft water, as soft water has a tendency to leach impurities from your pipes and faucets. It is possible to have the best of both worlds though. You can install a water softener and leave one dedicated cold water line for drinking water.

How Do I Know What Kind of Water I Have?

  • Taste: Some people think hard water tastes different. You may or may not notice a distinct taste. I find it tastes fresh and clean. Soft water, on the other hand, can have a definite salty taste to it, depending on how "soft" it is.
  • Public information: Many states, provinces, counties, and municipalities have a website or a town office where you can access information about groundwater or other water sources in your area. Maps are often available for your location, showing what kind of water you have in your area.
  • Testing: You can also choose to have your water tested by a professional.

Hard Water Treatment. Should I "Soften" My Hard Water?

We are fortunate to have a plentiful supply of clean, safe water in North America and in most parts of the world nowadays. Although the water in my town is certainly safe, we do filter our water for drinking and cooking.

We use a Brita water filter that simply screws onto our existing kitchen faucet. It cuts down on hard water scale in the glasses, the coffee maker and in our cooking pots. We also add about a cup of vinegar to the dishwasher's final rinse to combat water spots and scale build-up.

If you have a private well or dugout, you might consider a whole-home water treatment system, which can run to thousands of dollars, and requires professional installation. These systems most often include a pressure tank, various filter tanks, and a water ion exchanger (softener), and require careful and ongoing maintenance. Purchasing water may actually be more economical.

If you do decide that treatment is your best option, get recommendations from friends and neighbors wherever possible, especially if they have the same type of water as you. Do your homework—research your options carefully before deciding on a method or a company.

Common Water Treatment Systems & Costs

Type of FilterHow It worksLevel of FiltrationCost

Tap-mounted filter

Water is diverted through a filter on your tap

Removes most odors (chlorine) and some impurities (such as sediment)

Brita: $19.99 - Pur: $15.99

Pour-through filter

Water is poured in a vessel (pitcher) and sinks through a filter (usually activated charcoal)

Removes most odors, tastes, and some impurities (such as chlorine and calcium)

Brita: $19.99 - Pur: 29.97


Often installed under sink. Water from taps is diverted through the filter system before dispensing

Removes most odors and impurities, as well as filtering out some contaminents.

Aquasana AQ-4600: $186.99 - Cuno Aquapure AP DWS1000: $548.92

Helpful Information

This article is accurate and true to the best of the author’s knowledge. Content is for informational or entertainment purposes only and does not substitute for personal counsel or professional advice in business, financial, legal, or technical matters.

© 2012 RedElf


RedElf (author) from Canada on August 18, 2018:

Ours isn't bad for tea if we use a filter, otherwise it has a film on it and makes scum. Nasty. And we go through a pile of vinegar in the washer to keep it cleaned out :)

Ethel Smith from Kingston-Upon-Hull on August 15, 2018:

We have dreadfully hard water. It tastes OK to drink but quickly clogs pipes, washing machine,s shower heqds etc and means we have to use a lot of product such as shampoo to get a lather. We have used a water filter jug for a long time now as sometimes boiled water in kettle tases rubbish in tea.

RedElf (author) from Canada on April 30, 2018:

Hi, Peggy. I have a Britta pour-thorough as well as a tap filter. We also have large bottles of our local, filtered water on a cooler base. Comes in handy i the summer.

Peggy Woods from Houston, Texas on April 28, 2018:

We personally use Britta pour through filters in our home to filter out impurities. In fact we have 2 of them and keep them in our refrigerator. This was an interesting article to read. We must have closer to hard water than soft after reading this.

RedElf (author) from Canada on April 18, 2018:

Thanks so much, Rochelle. I'm still looking for a similar map of Canada.

Rochelle Frank from California Gold Country on April 17, 2018:

Very good (in depth) research. The world water map is very interesting, too.

Nell Rose from England on January 30, 2017:

Thanks for all the info, like Bill above I had no idea what it was too! lol!

RedElf (author) from Canada on August 25, 2015:

Thanks for stopping by to comment :)

I agree - soft water is nice for hair, not so nice for drinking.

amazmerizing from PACIFIC NORTHWEST, USA on August 24, 2015:

Great hub; Ive switched back and forth many times... read that as MANY and I would much prefer my water as lower end of hard... it still has that crisp fresh taste and not too many issues with the machines and buildup. Soft water just is so unmanageble, in my opinion. Thanks for sharing :)

RedElf (author) from Canada on November 04, 2012:

You are most welcome, Glenn Stok - we're all stuck with whatever water is available, but there are ways we can mitigate it. Thanks for the insightful comment.

Archa Ghodge, you are welcome. Thanks for stopping by to comment.

Archa from India on October 29, 2012:

Thanks for sharing the hub on hard water.. :)

Glenn Stok from Long Island, NY on October 24, 2012:

I knew that professional water soferners that are built into the incoming pipe use sodium that has to constantly be replenished. But I never knew why. Now after reading your hub I know and I understand what the difference is between hard and soft water.

This is very useful information that many people don't realize and take for granted. I can see why it's important to not drink soft water. Especially people with high blood pressure since the sodium can make it worse.

Your hub is very useful, since you explain very well about the positives and negatives with both hard and soft water.

RedElf (author) from Canada on August 17, 2012:

Thanks so much, unknown spy. Thanks for stopping by to read and comment!

DragonBallSuper on August 17, 2012:

Very informative hub. Glad to know more of this subject. thanks for sharing

RedElf (author) from Canada on July 25, 2012:

Trinity M, thanks so much. I hate the constant scrubbing, but I prefer the taste of hard water any day.

Trinity M on July 25, 2012:

Very interesting hub. We have hard water where I live and the scales on my taps and in my kettle can drive me crazy sometimes, however, for drinking it is really the best. When we go somewhere and have to drink soft water it never tastes “right” and we cannot wait to get back home. Voted up and interesting.

RedElf (author) from Canada on July 25, 2012:

moonlake, we had a special iron filter on our system, and that took care of a lot of the problem, but aside from "shocking" the well to kill the iron bacteria, the iron filter was the best we could do - that, and avoid using bleach, which reacted badly with the water to create even worse orange stains. when I lived there, we used a purifying still for our drinking water.

nifwlseriff, you are so right - hard water makes terrible tea. I found out just how hard the water is here when I added some bicarbonate of soda to boiling water in a pot on the stove. I was trying out an old remedy to clean a burnt pot. I was fascinated by the thick layer of scale that formed almost immediately, but eventually had to just scrub the pot.

Kymberly Fergusson from Germany on July 25, 2012:

I have incredibly hard water here in Leipzig, possibly made worse by very old pipes. Having grown up with softer water, I find the taste quite nasty, especially in green and herbal teas.

Boiling water, as you mentioned, does help somewhat. I find that adding a tiny pinch of bicarbonate of soda to the kettle helps remove the nasty taste, although it increases the scale at the bottom of the kettle (never pour out the last bit of water into your tea cup, ergh!)

moonlake from America on July 24, 2012:

We have hard water full of iron it smells and taste bad. We have a sofner on it. The softner really helps but I still won't drink it and it still leaves some rust stains on items. Today I had to clean my shower curtain liner because the bottom of it had rust stains. We get our drinking water from an artesian well near town. Voted Up on your hub.

RedElf (author) from Canada on July 24, 2012:

Thanks so much sgbrown. We had beautiful hard well water in one house we lived in - it was the best tasting, but our mother hated it in the wash.

Sheila Brown from Southern Oklahoma on July 24, 2012:

I am really glad I found this hub! We have very hard water from our well. It is the only water we can get as we live in the country. All ouf our friend all say that we have the best tasting water, but it can be a pain. I am so glad to find the tip about the vinegar for the diswasher. I get really embarrased by my glass looking so cloudy and spotty. Great hub, thank you for sharing with us! Voted up, useful and socially sharing!

RedElf (author) from Canada on June 11, 2012:

Thanks for stopping by, billips. Gabriola is certainly not noted for its water. My folks were going to retire there until they investigated the water issues there.

billips from Central Texas on June 10, 2012:

Interesting article - I drink a lot of water and have been a drinker of both hard and soft water for many years - I even drank untreated well water for five years with no ill affect - found out later that my well water was absolutely pure, a rarity on the little island of Gabriola - good hub with useful information for all of us - B.

RedElf (author) from Canada on June 06, 2012:

There's always a trade-off, it seems, vespawoolf. Best water ever was when we lived on the Queen Charlotte Islands (now Haida Gwaii).

RedElf (author) from Canada on June 06, 2012:

acaetnna, better safe than sorry, I say. I've been very lucky over my travels to have always had good water. Thanks for stopping by to read!

Vespa Woolf from Peru, South America on June 05, 2012:

Yeah, I know what you mean about softened water. It is salty. I think the best drinking water we had was in the Andes mountains, where the water is naturally soft. Of course, we still had to filter it because of the bacterial problems but nothing's perfect!

acaetnna from Guildford on June 05, 2012:

A captivating hub. I often wonder what I am REALLY drinking - goodness knows what they do to our water these days! I am a total advocate of filtered water, but even then I am not really sure just how pure it is!

RedElf (author) from Canada on June 05, 2012:

You are very welcome, vespawoolf. I think we are very spoiled... Our water is drinkable, but we filter it for drinking. On place I lived had a well, which was safe but hard. We had a water softening/iron removal system, and we distilled our drinking water because it was too salty after it ran through the softener.

Vespa Woolf from Peru, South America on June 04, 2012:

This hub caught my eye because water is a real problem here in Peru. I appreciate your explanation of the difference between hard and soft water. Since our water isn't drinkable, we distill for drinking and use filtered water for cooking. But since we use hard tap water for bathing, we're often left with dry skin and hair. Softening water isn't an option here, but at least we have water! Thank you for such an informative hub.

RedElf (author) from Canada on May 28, 2012:

...and that's what we "everyday experts" are all about. :D Thanks so much drbj!

drbj and sherry from south Florida on May 27, 2012:

I know that hard water and soft water exist, RedElf, but I never really knew exactly what that meant. Now thanks to your erudite explanation, I shall consider myself an expert. Well, maybe not a genuine expert, but certainly far more knowledgeable than before. Thanks to you, m'dear.

RedElf (author) from Canada on May 25, 2012:

Most welcome, kj force. I agree about ice water, too. It's my favorite drink, even before coffee :D

kjforce from Florida on May 25, 2012:

Thank you for the educational hub great research, very informative. I have always had well water,even as a child, and have always had good spring water...but now we also use a filteration system...nothing like an ice cold water !!!!

RedElf (author) from Canada on May 25, 2012:

My mother nearly went crazy over her laundry - I have been fairly lucky, but yes, hard water makes stain removal such a pain!

sadie423 from North Carolina on May 25, 2012:

I never had to deal with hard water, as we had city water. But we have recently moved and now have spring water, and while I don't mind it for most things, clothes washing, particularly cloth diapers is a pain with hard water.

RedElf (author) from Canada on May 25, 2012:

Thanks, CWanamaker. We have very hard water here, too, which is why we filter our kitchen tap. The mineral deposits burned out a coffee pot every year - which is still a lot less expensive than an evaporative cooler. :D:D:D

RedElf (author) from Canada on May 25, 2012:

Happy to have added to your store of knowledge, BP.

billybuc, you, too, are most welcome - I doubt there's much else about which I could educate you :D:D:D

Christopher Wanamaker from Arizona on May 25, 2012:

In Arizona we have very hard water. Anyone living out here that uses an evaporative cooler to cool their home knows that they pretty much have to replace the whole unit each year due to the amount of mineral deposits that accumulate in it. Luckily the home that I have now is relatively new. So hopefully I don't have to worry about corrosion and mineral deposits for a while (aside from regular maintenance). Our water does taste a bit funky, but it is safe to drink. Great hub!

Bill Holland from Olympia, WA on May 25, 2012:

I think it's amazing that I am sixty-three years old and never knew what hard water was. Thank you for shedding light on this and for educating an old man. Great hub!