UV vs. chlorination

tightasadrum

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Due to a recent family sensitivity to bacteria, I find I must get seriously active in the purification of my well water system.

question: UV or Chlorination of the water
 
UV works well when you have new bulbs and no slime in the chamber. Also, if you water has organics or any sediment it will reduce the effectiveness of the UV.

Chlorine is more forgiving of these things but creates it's own set of issues. As long as you keep the residual chlorine levels more or less constant and the water quality does not deterioate you should keep the nasties at bay. The downside to chlorine is chloramines and a host of other side reactions that can corrode pipes and make the water taste bad.

Another option might be ozone. Ozonation is not all that complex and will do a decent job at keeping the water free of nasties while preserving the water quality. But, ozone is a strong oxidizer and can attack rubber and other things so it is not perfect either.

Chlorine is the chemical of choice due to the relative ease of use, very good kill dynamics and cost. Do some research on all three before you decide.

Don't forget about pH and water ions. A pH that is too far from neutral can do a lot of damage to plumbing and your body. It also makes the sanitizing agents less effective. Hard water creates a whole other set of issues.

There is no right answer without knowing your current water quality and what you would be willing to do to control it.
 
Thanks for the replies. My water test have shown low iron, pH around 5.8, e-coli of zero, and coliform of 75ppm. The guys that sell the systems have offered several different options.

1. Shock the well with Chlorox and install a neutralizer for the pH.

2. Install a neutralizer, conditioner and chlorine system.

3. Install a neutralizer, conditioner and UV lamp.

No one has mentioned the ozone method. I don't know if any of the guys so far even use it.

The UV proponent said that the conditioner is required to keep the water clear and free of whatever attenuates the UV from doing an effective job.

Is their a brand name that stands above all others in effectiveness and durability? I'm willing to pay more for value but not for a sales pitch.
 
Thanks for the replies. My water test have shown low iron, pH around 5.8, e-coli of zero, and coliform of 75ppm. (coliforms are not measured in ppm. Did they mean cfu/ml? ) The guys that sell the systems have offered several different options.

1. Shock the well with Chlorox and install a neutralizer for the pH. With a pH of 5.8 (acidic) you need to neutralize the water before chlorinating it or it won't work as well.

2. Install a neutralizer, conditioner and chlorine system. What are they "conditioning"?

3. Install a neutralizer, conditioner and UV lamp.

No one has mentioned the ozone method. I don't know if any of the guys so far even use it. See above post.
I assume this is a closed well that is a lined pipe into the aquafer layer with a pump to draw the water up to your house. There is no way to neutralize, condition or chlorinate the "well" in this arrangement. You have to treat the water after the pump but before the house distribution system. You can do it in a small bump tank or a larger surge or storage tank. Some systems let you do it in-line with various dispensers, cartridges or housings. I don't have any brand names for you but folks with a swiming pool might as the equipment is the same.

Get bids from different companies.
 
#1 son works for Trojan Technologies, world leader in UV purification. Head office, London ON.

They usually do whole municipal systems worldwide.

Chlorine sets up it's own set of contaminants.
 
I assume this is a closed well that is a lined pipe into the aquafer layer with a pump to draw the water up to your house. There is no way to neutralize, condition or chlorinate the "well" in this arrangement. You have to treat the water after the pump but before the house distribution system. You can do it in a small bump tank or a larger surge or storage tank. Some systems let you do it in-line with various dispensers, cartridges or housings. I don't have any brand names for you but folks with a swiming pool might as the equipment is the same.

Get bids from different companies.


You're right. I looked again, and the units are mpn/100 ml (mpn=most probable number) equivalent to colony forming units (cfu)

One system was Ecowater Systems

Stage ONe: ETF 2100 PF10; sediment removal; acid neutralizer; taste and odor removal with activated carbon; $2500

Stage Two: ERR 3500 R-20; water softener; carbon filter for chlorine taste and odor removal; $3900

Stage Three: UV lamp module; $900

Can get the entire package for $6100 plus 8% tax

I've got a call in to another guy for basically the same equipment. I hope to get him out next week to assess it all for me. His total package was around $5000 as I recall. The Ecowater Systems guy claims his is the best system on the market, so it costs a little more. But he gave few details to support that claim.
 
You can buy a lot of bottled water for $6,100.

I agree Ed, and that's what I've been doing for two years now. Trouble is, it's not just about drinking water. Every day that goes by the piping gets thinner. Yesterday I tried to replace the shower nozzle pipe that the cleaning lady broke. When I tried to back it out of the wall, the threads broke off inside the wall because of thinning.

So I'm committed to doing something about it. I considered replacing all the piping with cpvc, but the house is two stories. That second floor would really be tough to get at. Anything I do will not be cheap, so I may as well work toward the best overall result.
 
A pH of 5.8 :confused: You may have no iron in the water going into the house, but I bet there is a lot more by the time it gets to the second floor! The most common acids in well water are H2S and CO2. I'll bet your water stinks. (It sounds like Lithia water. Do you live in Ashland, OR?)

It looks like you will have to buy a complete water treatment plant to treat all the water going to the house. I am used to industrial water treatment. Household applications are another world for me. SteveR seems to know a lot about domestic applications. (Is this a great forum or what? :D )

Just brainstorming here:
1) Ion exchange up front to get rid of the hardness and the acid gases. Removing the acids will automatically adjust the pH. (SteveR, will a domestic water softener get rid of anions? I only think of it in terms of calcium and iron.)
2) followed by chlorination. Ozone is fine, but it leaves no protective residual.
3) followed by activated charcoal filter to get rid of organics, chloramines left over from the chlorination step and act as a filter. You probably will have to change this often. Maybe add a string filter in front of the charcoal filter later if the charcoal plugs up too quickly.

Water treatment equipment likes to run at a steady flow. I am thinking that all this would be upstream of your tank.

SteveR, does this make sense?
 
Ed, that was an inside Oregone observation. Did your parents try to get you to sample that fountain when you were a kid too? :LOL:

Tight, I am not certain if the problem is your household plumbing system or the well. If it is the well have you considered drilling a new one? I know it isn't cheap but when it comes time to move no buyer will want a home with a contaminated well.

If you problem is in the house plumbing then treating the well water won't help either.

It could be that the chemical characteristics of your well water has also done damage to the household plumbing. In that case we are back to either drilling a new well or treating the well water.
 
Brat: No, I did it to myself! (I still sneak a sip when I get the chance.)

Treating the water will not heal the damage done to the pipes already, but it will stop the damage.

Another well may be difficult. There is no guarantee that the new source will be any better. There may be a moratorium on new wells, too. There is many places these days.
 
You are correct Ed. Drilling a new well can be throwing money down a hole, and the new well would need to be certified by the health department. When this home is sold the well will need to be re-certified in most cases. This situation is frought with problems.

I am a Commissioner in a small sewer district. We use UV to clean our discharge for one reason: UV has no enviornmental issues and removes bacteria so throughly that the discharge is potable. If bugs are the OP's problem UV would do the job.

UV doesn't change the chemical composition of water so if it is high in iorn or sulphur it won't change that problem.

Me, I would call water districts in my area and find out if any are using UV and talk to them (many will use chlorine). Ask the UV folks about their experiance.

If minerals in the water is the issue try to find water districts who deal with that.

Then I would ask each of your bidders to provide a list of 5 customers who have installs that address problems similar to yours that over a year old. Talk to those old customers.
 
Overwhelming. One of the water treatment equipment guys recommended UV. Says he and all his neighbors, all on wells, use UV with neutralizer and softener in the line first.

Another water equipment guy suggested just shocking the well with clorox periodically to take care of the coliform issue and putting in a neutralizer to raise the pH. (Pipes have definitely been damaged by pH.) However, the other guy said that raising the pH would harden the water leading to other problems, and I should also install a water softener.

This is like trying to squeeze jello.

I also considered drilling a well, this one I have now is bored, but then I figured I would probably have problems with that one too, just different. Decisions, decisions.
 
I also considered drilling a well, this one I have now is bored, but then I figured I would probably have problems with that one too, just different. Decisions, decisions.

My experience tells me getting good well water is a combination of skill, science and luck.

My well is 800' deep in a limestone karst formation. The well is cased down to 125', then sealed at that level with only the 2" pvc pipe, wiring and submersible pump extending below that. My water is harder than...well, it's very hard but otherwise good.

Contrast that to my neighbor 300 yards down the road. His well is at the same depth and configured the same - with a key exception: no casing and no seal. His water is unfit for human consumption - unless you're looking for an alternative way to prep for a colonoscopy.

My theory is that contaminants from the surface are leaching into his well and causing his problem. He agrees that's probably the cause, but since he can't be sure he was unwilling to spend the money to case and seal it. He chose to sunk big $ into a rainwater collection system, including tanks to store 10,000 gallons of water, enough to last him three months.

Unfortunately we just went 5 months with just over an inch of rain - not a very good situation for him. He ended up running 150' of garden hose to his nearest neighbor to borrow some water to tide him over.
 
...Just brainstorming here:
1) Ion exchange up front to get rid of the hardness and the acid gases. Removing the acids will automatically adjust the pH. (SteveR, will a domestic water softener get rid of anions? I only think of it in terms of calcium and iron.) You can buy anion softners but the normal residential unit is cation. I don't know how much acid will be removed/neutralized in a cation resin water softener.

The OP did not state the hardness but when an acid neutralizer is added to the system a cation softener will be needed to remove the Ca and Mg added to neutralize the acid water.
2) followed by chlorination. Ozone is fine, but it leaves no protective residual. If you chlorinate do it after the softner as the chlorine will degrade the resins. It would seem chlorination of the well (shocking it) might be a short term fix for the current bacerial problem. The coliform load is high but the E. coli count is zero which might indicate a non-human source of the coliforms which would usually rule out contamination from a septic field. If this is the case, then shocking the well might knock out the contamination.
3) followed by activated charcoal filter to get rid of organics, chloramines left over from the chlorination step and act as a filter. You probably will have to change this often. Maybe add a string filter in front of the charcoal filter later if the charcoal plugs up too quickly. This may be overkill in a residential system. Also, the carbon will remove the chlorine residual and can create a microbiological soup in the carbon filter. The OP already has issues with bacteria and family sickness so I would opt out of the carbon filter.

Water treatment equipment likes to run at a steady flow. I am thinking that all this would be upstream of your tank.

SteveR, does this make sense?


An equipment train seems the best approach.

Pump--> acid neutralizer --> filter --> water softener --> chlorinator (only if needed after shocking the well) or a UV system.

This will neutralize the acid water, filter any calcite or white sand from the neutralizr, soften the now hard water from the acid neutralizer, and then sanitization prior to distribution.

Use some key words in Google to shop around and see what the costs might be for the components. Generally, a good neutralizer might run $1k as would a good softener. A UV system a bit more. Then there is installation (no idea of the costs for this). Chlorinators are a bit cheaper and should have less maintenance.
 
Just an update.

1. Have concluded that the best way to be separated from your money is to hire someone to turnkey the installation of a well-water treatment system.

2. A good way to learn a lot about it, is to have several people out to look at the water and offer high priced solutions.

3. Prices for treatment equipment is easy to find on the internet, and it's a lot cheaper that having it done for you.

4. It doesn't take a rocket scientist to hook up the equipment. I'm not sure what the guys in the installation business get paid to for doing?

5. I plan to install a neutralizer and add sodium chloride to the neutralizer tank in the well house, and I'll probably install a carbon filter in the basement to get the chlorine out of the water before I use it. (If purchased locally: Soda Ash neutralizer with tank0, due to very low pH of approximately 5.8 - $$890; carbon filter - $900). I may be able to beat the prices a little buying them on the internet, but won't do it unless it's quite a bit cheaper.

6. Cost to do all this appears to be under $2000 with me doing the installation. One guy representing the ECO brand wanted approximately $6100 plus sales tax.

I've learned a lot about this water business, and chemistry was not my strong subject in engineering school. :D
 
tightasadrum,

It appears from your post (andthe $$ figures posted) that you may be planing to treat all te household water for bacteria/microorganisms. That seems like a very costly way to go.

Our well water was very hard, had some iron, and I was concerned about bacteria. I shocked he well (which will never be a permanent solution, but sure got our iron-reducing bacteria under control) then installed a regular ion-exchaage softener. That's al I did to my general house water. Downstream of this, for drinking water, is 30, 15 5 micron filtration, RO, and UV for drinking water (separate tap at sink ad for icemaker.) This has worked really well.

I think you are on the right track with your neutralizer approach, but then I would avoid al the big troube with chlorine by going with the RO and UV fo just your drinking water. And, don't be buffaloed into paying thousands of dollars for a UV system--you need to spend only a few hundred dollars for a 5 gpm system, which is all you'll need for simply drinking water. Your water won't taste of chlorine and will be free of almost any kind of microorganism. In fact, if I wanted to be absolutely sure of microrganism-free drinking water, I'd install two cheap (approx $150) units in series to protect against te unlikely case of bulb burn out rather than buy a very high-buck system wth an alarm, etc. Then keep a few gallons of bottled water in storage in case you lose power for a few days.
 
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