Is water making your cat sick? Is it making YOU sick? It’s fairly common knowledge for American’s not to drink the water in undeveloped countries because of the risk of diarrhea. Yet we take for granted the water coming out of our faucets (“tap” in the UK) at home.
I’m not sure about the water supply in countries outside of the U.S.. Here we have a choice of two kinds of water coming out of our tap. The first is “city” water, meaning pipes have been run from the home and tied into a system where a company provides water for a charge. The second is well water, meaning the source of home water comes from a well dug on the property. Both of these have their dangers.

I’d like to start with well water first. I had well water back in the mid 1980’s. The taste was pure and there was no smell to it. The main concern with well water is to have the well dug as far from the septic system as possible so it doesn’t contaminate the water. One contaminate in well water that can cause diarrhea is sulphur. When sulphur gets into ground water it can cause hydrogen sulfide gas. Sulphur contaminated water can be treated with chlorine, but you’re putting yourself in a Catch 22 situation if you have to add one chemical to offset another. It’s easier to just install a filter. I can tell the readers here from experience that migraines may be caused by sulfites and nitrates. So if you have well water and it smells bad and you’re suddenly having headaches, keep that in mind.
I noticed a change in my cats when I moved back to the city in November of 1993. My gray tabby cats lost their beautiful silver sheen. Within six months, their fur had a brownish tint. I invested in a water filter once that happened and their fur once again grew out gray/silver. It was easy to determine the problem as this was the only change in the diet.
Most “city” water companies release a yearly report with specifics of the quality of the water. If you’re not satisfied with the report, there are companies out there who will test your water for a small fee. Even if you have the purest well water, it’s good to do an occasional analysis, especially if it develops an odor or you begin having digestive trouble.
The water where I live has become quite nasty over the past few weeks. The chlorine smell is stronger. In the U.S., chlorine is added to make the water safer and fluoride is added to help teeth. For those of you who think fluoride is a good thing, Google “skeletal fluorosis.” Sealy has developed a bit of diarrhea since we noticed the change. His tests didn’t pick up anything out of the ordinary. No parasites or other illnesses. One of my friends has a cat who had diarrhea. I told her it could be in the water and suggested a water filter for her faucet. Since installing one, her cats bowel disorder has gone away.
There’s a protozoa called Giardia that thrives in contaminated drinking water. Parasites may cause diarrhea in cats over a period of time. Giardia can come on suddenly as well as violently in cats.
Today I took my own advice and purchased a PUR water filter for the faucet. It’s exactly like the one I had years ago and cost $20. There are also pitchers with a built in filter. Those last for about 40 gallons while the faucet kind is good for 100 gallons or more before it’s changed. My cats go through a LOT of water.
There’s more to worry about that bad taste and chlorine and fluoride side effects. Until recently, people were told to flush old drugs down the toilet if they had reached their expiration date. This has really taken a toll on our water systems. According to a report released by USA Today back in 2008, antibiotics, mood stabilizers, anti-convulsants and sex hormones have been found in the drinking water of at least 41 million Americans. Between people flushing unused drugs and the body eliminating a small portion of ingested medications, this is a major concern that’s affecting drinking water everywhere.
Here are some of the problems unfiltered tap water may cause.
- Diarrhea
- Constipation
- Headaches (sulfites)
- Cancer (chromium, radon)
- Bone cancer (fluoride)
- Acne
- Joint pain
I also read a few articles concerning weight loss and not to expect it to happen if you’re not filtering all of the water you drink. Something about good bacteria in the body being offset by chemicals in the water. It makes sense.
Water filter systems are a good investment. It’s cheaper than buying distilled water (although that’s an option. There are also online instructions to make distilled water at home). The rule of thumb is the costlier the system, the more contaminates it will filter out. Also, think of the thousands of plastic bottles that can be kept out of landfills by using a good water bottle and filtered tap water!
I didn’t intend for this article to turn into how unfiltered water can affect OUR health. It just turned out that way. I’m not going to list a bunch of references of articles I read up on while doing this article. If you’re interested in learning more about how tap water may cause a medical condition, just Google “does tap water cause __________.” Several topic will pop up.
This is very scary. Unfortunately, it’s legal. Water is allowed to have a certain percentage of contaminants and still be determined safe for drinking. Every now and then an area will have a “boil water” order on the evening news when contaminants are found. Other than that, we usually trust the government and our water companies to keep our drinking water safe.
Readers, we have to take matters into our own hands when it comes to the health of our cats as well as ourselves.
Have any of you had any health problems you believe were caused by the water in your home? Did they go away when you purchased a water filter? I’m just curious.
Elisa
Original photo on Flickr.
I’m still wondering whether filtered water is better than distilled water. I’ve heard distilled water will prevent UTI’s
Many thanks for your comment which I found very interesting. I wonder if it caused an allergic reaction causing itching.
This is why I am at this thread today as well. My cat recently does what I call “angry licking” at his sides and has no fleas or other indications of why. Despite using a Brita filter I suspected our water is bothering him and possibly myself as well.. I’ve discovered (as stated above in the thread) that cheap home filters only reduce certain contaminants – not completely remove – and some they don’t touch at all such as fluoride.. Good news is after just a couple days with high quality bottled water ( note some have been shown to still contain fluoride etc) he hasnt stopped completely yet but it has been greatly reduced already. Now I’m trying to decipher which potential contaminant is in my water…
This is an old thread but I’d like to point out that box doesn’t say “remove” it says “reduces” which is a very important distinction particularly as it doesn’t specify by how much for anything listed. Also filters like this don’t remove flouride.. (Which can be an allergen to cats). Im no expert but in my recent research of this topic that seems to be to be the case with most simple and most affordable filtering systems. However its certainly much better than nothing and glad it worked for op’s cat.
There is a really interesting comment, Gail. Thank you very much for your observation. It certainly adds to the page. I am not sure that a filtering system would be economically viable. Caps don’t drink a lot of water anyway and if you buy bottled water for yourself then you could share it with your cat and that may work out cheaper in the long run. I’m just guessing though.
My cat always drank tap water until we relocated. He ate the same food, but the water was different, smelled and tasted different. He developed crystals, therefore began urinating outside of his box. I suppose he associated pain with his litter box. Took him to the vet, and sure enough crystals. I switched him to bottled water. No more problems. I’m still trying to figure out if I should get a water filter system or not.