High Copper Content In Domestic Water

Just guessing I would say there is some electrical appliance grounded to the copper water line....The Ph doesn't appear to be acidic enough to cause degradation in the lines...I would disconnect system ground and test for voltage, then hunt it down...

I am going to research the polyphosphate with our chemical supplier and see if this is a feasible option. Our chemical supplier has noted that it may take several months of running hard water to build up enough calcium in the plumbing but I am concerned about the hard water running through my boilers for this long period of time. I will discuss with the boiler rep. to ensure we are not voiding our warranty. Short term we will flush the system at the fountains daily and continue to test for contaminents. This is the first time I have used the CR4 forum. It seems to be a very good resource to exchange knowledge. I hope I can be of help to others in the future.

PP is a common strategy for chicken farms where they want the chickens to get much of their dietary calcium from the water. Softening the water just removes the desired calcium so they use PP to sequester the calcium and prevent over encrustation problems. Here is at least one article and use in potable water situations.

Thanks for the information and link. I work on a poultry farm at the moment, and we are having encrustation problems in the hatchery which plugs the mister nozzles. There has been discussion about installing a RO unit just for the hatchery, but that is going to be relatively large and costly.

PP may be the way to go vs RO, I'll certainly discuss it at work.

Cheers,

Duane

kevinm,

You think a LSI (Langelier Saturation Index) of -1.8 is "extremely corrosive" ?...

Well, several months ago I did some water testing in a residential building in Manhattan. The LSI of the incoming water being provided by the City's water distribution system was - 3.90. Now THAT'S Corrosive!

Agreed! The usual interpretation of extreme levels of encrustation or corrosivity when using the LI for domestic water plumbing is anything outside of the range +1 to -1; so yes -3.9 should be very "THAT'S corrosive" to plumbing. We would see some of those low levels in landfill leachate. Some of the waters used in the shield area of Canada have very low alkalinity and low pH. The LI is frequently low and much less than-1. Manhatten should be following the lead copper rules laid out for such levels. The LI level of -3.9 is a localized problem and may have many causes. Here is a report I found but have not read.

I do hope you have not been drinking this water. I suspect lead and copper would be above the regulated levels. Something that comes to suspect is a level of tuberculation and pitting in very old plumbing. The underlying surface of many tuberculated pipes is very low pH water and harbors many metals from lead, copper to arsenic.

Thanks for the comments. We are testing the langelier index today and are also bypassing the softner for the next month or so to increase the calcium content to help coat the piping. The temperature I believe was not taken when the sample was drawn, so it may be incorrect. We are also looking in to softening the hot water only.

Well, the softener is there for a purpose, and the effects of bypassing it on the downstream equipment need to be considered carefully before carrying it out.

There seems to be a difference of opinion on whether the Langelier Index is a good indicator of corrosivity....In any case I would be interested to know what the findings are...

The Langelier Index is an empirical tool. Just like most engineering formulaic approaches and will give varying results depending on the circumstances. The whole topics of water chemistry and corrosion are complex which is why failure analysis and experience are required to solve problems when they occur.

The particular discussion thread you refer to relates to the corrosion of steel and water. This is a completely different problem than the corrosion of copper and water. Steel pipe will form a voluminous corrosion product which eventually chokes the pipes ability to carry water. The phenomenon of copper corrosion and pinhole leaks is common and widespread.

Duane

I don't agree that the corrosive nature of water (ie; the tendency to deposit calcium carbonates and other minerals in pipe, or not, is related to the pipe material itself.)would have a different result in copper as opposed to steel.. or anything else for that matter...

Handy calculator...

http://www.awwa.org/Resources/RTWCorrosivityCalc.cfm?navItemNumber=1576&showLogin=N

Many years ago when I was a registered professional engineer, I used to be a regular contributor on the NACE corrosion forum. There the engineers acted professionally and gave opinions or answers in areas and on topics that they had experience and knowledge.

I see that we have nothing to discuss Mr. SolarEagle. You have no knowledge of this topic and are acting like a troll.

Adieu.

I have many years of experience in water systems of all types as a troubleshooter, design, installation and maintenance...more than you could ever hope to have...That doesn't mean I know everything like you do, so I'm still willing to learn....

Consider re-running the pipework in plastic instead, with those runs downstream of the water softeners starting first. Once these runs have been re-done, re-test for dissolved copper and take a view on which runs to do next, if any.

Hi all...

It's been a while since I've commented on this forum.

some thoughts;

1. A secondary water treatment is a good option. I did a lot of research into the use of sodium silicate back in the late 1990's and that shows great promise in my opinion. One hospital in Vancouver used this system to treat all their water and they had no pinhole leaking problems, and some of their copper piping from the 1940's or 50's was still in use.

2. Without additional water treatment you will likely experience corrosion failures in the pipes within 10 to 15 years, or earlier in re-circulated hot water systems. So your purified water becomes a liability to the water quality where it's in direct contact with metal for extended periods of time. Drainage piping may also be affected in areas over time.

3. Brown staining is likely one of the copper oxides forming. Copper chlorides will usually show up as greenish blues, and are the result of over-chlorination. A good stable corrosion product will adhere to the inside of the copper pipe and reduce corrosion over time. These tend to be deep-black/greens (malachites). Brown corrosion product flakes away and leads to pinhole leaks.

4. Pinhole leaks into wall cavities can present a future health issue. Moulds may form and SBS may ensue.

5. Calcium build-up will present other issues so removing the water treatment for hardness is not suggested long term.

6. Replacement with PEX (I used to use Wirsbo) is an excellent idea (if you can afford the re-pipe). Consult your local plumbing and building codes for other requirements, such as firestopping, etc.

That's all for now... have to get to work!

Cheers,

Duane