Hmm, How Clean Is Well Water?

A “boil-water” warning was issued for my area - concerning only those on municipal water. Now, this got me thinking…why doesn’t my own private well require chlorination before drinking? These alerts are often issued when heavy rains wash an excessive amount of bacteria (typ. from farm animal feces) into the water. Isn’t my private well just as much at risk??? In general, there is always some amount of bad bacteria in the water, so how is it safe for anyone to be drinking from a private well??? Hmm…

I WAG, having grown up in the area of my current residence, my local well isn’t too different from the municipal water sources - from which I once drank. Perhaps my body is well-adjusted? (But, this would imply the chlorination isn’t doing anything, right?) This could explain traveller’s diarrhea while travelling within the US…which always puzzled me as a kid, but I never thought about certain areas being on private, untreated, wells…to which the locals are long-since used to.

Is my WAG perhaps the overall answer? :confused:

  • Jinx

No, well water can vary GREATLY from public water due to the distribution of watersheds in the region.

I’ve got a well and don’t chlorinate much…just the occasion shock to the system.

What I have to do is maintain a system that removes iron particles from the ground water. We’ve got a lot of iron oxide in our water.

A Pratchett quote springs to mind. I’m sure i’ll get it slightly wrong but heres the jist

“For years people have considered newt inhabitation to be a good sign where water is concerned, never once asking themselves if the newt’s got out to go to the toilet”

Private wells have to be approved by the local health department before a Certificate of Occupancy can be issued. In the instances of a shallow well, the water is much more likely to be contaminated through leachate and runoff because of the shallowness of the well and the local origin of the water.

Municipal systems (and most bored wells installed at homes these days) go much, much deeper into acquifers that are less likely to be contaminated through leachate and runoff. For instance, I live in Central VA, but the water in the well at my house is in the Potomac Acquifer, is about 400’ under ground, and has its origins several hundred miles away.

If your municipal system is supplied by a reservoir or surface water intake (like from a river), it is treated at a water treatment plant.

Boil orders are sometimes issued because a broken pipe has allowed contaminates into the system at a point past the filtration and chlorination point.

Jinx, the answer is going to vary greatly but it’s been my experience that in general, absent of any local polluting source, well water is pretty clean. Obviously, YMMV. The last well field I worked with was relatively clean of pathogens, but had extremely high TDS (total disolved solids) thanks to subsurface evaporite deposits (mostly gypsum).

JC, might those iron particles be rust from the well casing? In my aforementioned well field, there were tons of little flakes and chunks of such particles. A well camera revealed that the old metal well casings were extremely rusted-out, and that this was the very likely source (there being no other likely source) for the particles.

We’ve got a pellet chlorinator on our well, but only to control iron bacteria. They are sometimes used to control fecal coliform.

I’d be doubtful about that. It’s a new well installed in 95.

But that’s worth checking. Thanks for the tip.

In many states, the Public Health Service (or its equivalent) will test private drinking water supplies for a small fee.

If you’re concerned about your well water, it might be prudent to call up the Health Service and see what they suggest. A cheap fecal coliform count may be worth it, just for the peace of mind.

What a coincidence. My co-worker and I were just talking about this topic earlier in the week.

He is in the process of purchasing a home on 3 acres. The house is on a well. The current owner says he “performs shock chlorination once a year.”

We’re also on a well, and I had never heard of this “shock chlorination” stuff. So I did some asking around:

  • Another coworker who lives on a farm has never chlorinated his well, and he says it’s fine. Furthermore, the house his father grew up in had a well, the house his mother grew up in had a hand dug well, his grandparents had a well, and his great-grandparents had a well. To the best of his knowledge, none of them had ever added chlorine to their well. Ever. He also said a buddy of his performed shock chlorination on their well last year, and it took weeks to flush the chlorine out of the pipes. His buddy swears he’ll never do it again.

  • My stepfather grew up on a house with a well. The well was installed in the 1940’s. He still owns the house, but doesn’t live there. To the best of his knowledge, chlorine has never been added to the well. Ever.

  • I grew up on a house with a well. The well was installed in the 1950’s. My mom still lives there. To the best of my knowledge, chlorine has never been added to this well. Ever.

  • Our house was built in 1988. We bought the place in 2001. According to the original owner, the well has only been chlorinated once – when it was first installed. When we moved in we had the water tested. The results were perfect. In other words, the well went un-chlorinated for 13 years, and the water has been proven to be fine.

So as you might suspect, I am very skeptical about “chlorinating” a well. It is my opinion that, if someone chlorinates their well on a regular basis, then perhaps there’s something wrong with the well or associated plumbing.

In some areas in which the water has a high iron content, the underground water supply has iron bacteria already in it.

The bacteria live by oxidizing free iron in the water and will plug the well if not chlorinated. The chlorine works as much by oxidizing the iron before the bacteria can get to it as by killing the bacteria.
It’s not my well. My nearby neighbors wells have it too. If I had a new well drilled, it would most probably have it.

Other reasons to chlorinate are that hand dug wells near concentrations of livestock are sometimes contaminated with fecal coliform. With drilled wells, it is less common. I would be very hesitant to drink out of a hand dug well unless I had it tested regularly.

Wells vary greatly in water quality. My sister had a well that was so contaminated with coliforms that the water was not potable. She couldn’t make ice, or drink tap water. She even used bottled water to brush her teeth until the well was moved. The well was dug by the previous owner downhill from the septic field and was being contaminated with septic run-off. Fortunately I worked in a lab where we frequently tested water and tested her water regularly free of charge.

Your water quality depends on the location of the well in reference to your septic field, the location of your property in reference livestock, and any other ground water contamination including chemical contamination from farming.

The well doesn’t require chlorination because unlike municipal systems sewage and potable water don’t commingle. In a municipal system sewage, drainage and potable systems run in pipes along the same system. In addition, generally sewage treatment and potable systems are run in the adjacent reservoirs. If an overflow of the sewage drains into the treated system (potable) the the boil warning is issued. This also happens in farming areas where heavy rains cause the treated reservoirs to be contaminated with run-off from farms.

Regarding private well water: my “Waterworks Operators Manual” says: “Aquifers in their natural state are generally free of bacteriological contamination due to the ability of the soil to remove bacteria by filtration”. Of course, there are exceptions, as others have pointed out. Sounds as though yours is fine to drink.

light strand the drinking water, sanitary sewer, and storm drain lines sometimes run along the same side of the street, but they are not supposed to be in the same trench; if a drinking water line is within 6 feet of a sanitary sewer line, it must be in a casing. I think you knew that, but I wanted to make it clear to other readers. :wink:

One of the functions of chlorination is to keep a chlorine residual in the system at all times, regardless of how far away from the well the pipe is. The private home well doesn’t have this problem, since the water is used as it is pumped.

As municipal water is pumped out of the well into a tank, it may have a “sit” time of several hours. After sitting in the tank it may then run several miles to the other side of town. So, a certain amount of chlorine is added to keep bacteria from growing during this time. Not only would one consider infiltration (as light strand said) and contamination by backflow but the naturally occuring bacteria in the system - pipes, fittings, etc.

My grandparents have a well and have lived on the property for…well…most of their lives. My great grandmother lived their her entire life without negative effects from well water. Unless, of course, she would have lived past 102 had the water been treated or from a more pure source. Now my parents live with well water…the same well, in fact, that my great grandmother drew from.

However…I just don’t get it. The whole lot of them are crazy. As soon as I got away from it for awhile, I noticed how horrible it was when I went back. The water actually STINKS. I can’t stand the taste of it. It’s full of gas of some sort and smells faintly of sulfer and a few other things I can’t quite put my finger on.

On top of that, showering in it gives me an instant rash…mostly on my face, but on other areas of my body too. It also worsens any skin problems I might already have, which normal people get on occasion, such as acne, dry skin, bug bites, etc.

I’ve been after them for awhile, expressing the opinion that it CAN’T be safe, and surely the farm chemicals my dad uses have leaked into the water over the years. Some of the information here has educated me a bit, but what IS the deal with our water? Could I simply be allergic to something in it? How could it literally STINK and give me a rash and still be safe to drink?


Sexy, you might check out the American Water Works Association’s web site for theirFAQ which may answer your “stinky” question:

Also, sometimes water builds up a smell if it stays in the water heater too long. This might be the case for your grandma if she and grandpa don’t use very much water. As for it making you break out, it may have naturally occuring chemicals in it which you are allergic to:

I frequently switch between municipal chlorinated water and well water with hydrogen sulfide in it (to noticable amounts). I aslo want to add that I have lived my whole life with chlorinated water and I am in a water district that goes easy with the chlorine now.

I have never noticed the chlorine till I started using the well water (actually when I came back and use the muni water).

When I start using well water I really notice the hydrogen sulfide, it fades and within a day I rarely notice it.

When I come back to using muni water, I really notice the chlorine, it burns my eyes in the shower and I taste it. It takes about 2 days till I don’t notice it.

If I had my pick I would choose the hydrogen sulfide well water over the chlorinated muni water, it just seems healthier.

and AFAIK the well has never been chlorinated and AFAI’m concerned that’s the way it’s going to stay!

Thanks for the answers! As far as I’m concerned, that clears up the mystery. I believe my dad when he says it’s safe. My only problem, is that unlike kanicbird I don’t get used to it quickly when I return to my parents’ house, which I plan to do next week. And in fact, the longer I stay, the worse my rash gets. But knowing that it’s something minor and not some horrible poisonous chemical nightmare makes me feel better. Plus, it always goes away almost instantly after I shower at home.

Thanks again!