Lead in domestic piping

[RBM]

I'm trying to determine what are the known causes for the lead in 30 year old domestic piping system, to begin leaching into the water. A lead test six years ago showed no lead. There is lead in the well water, but it is filtered out before entering the internal piping system. This lead is coming from within the piping system itself, and began to leach recently. Any info regarding what to look for, and solutions for solving the problem are appreciated

[Pete C.]

I'd look for issues with the filter between the well and the internal piping, any new leaded brass fittings installed recently, any notable changes in the PH of the water, and otherwise talk to some experts.

[Lefty]

Domestic piping system meaning "copper piping with 50/50 soldered joints"?

There is no reason to believe the solder would all of a sudden start to deteriorate to any great degree. I've seen some really, really old lead systems for water supply and drainage too and it does'nt seem like there is anything you do to corrode or degrade it visibly. I would look at the filter system for effectiveness, and also compare well water tests with older ones to look for an increase there. If indeed it proves to be the few joints of lead on the interior piping, all you can do is repipe with a lead free solder or other non-soldered system such as PEX.

[RBM]

The water after the filters is lead free right before the internal piping, then the water at the taps have high lead levels. Any new plumbing in the house has used lead free solder

[beecrofter]

Solder and brass which often contains 2% lead for free machining. here the water department adds lime which puts a layer between the lead and the water. Never prepare food with hot tap water. What kind of levels are you seeing? Pipe is cheaper than a few sleepless nights or disease.

[John Keiser]

What are the levels you detect? The level may be within the range of error for the test. How comfortable are your that either the 6 year-old or current test was accurate?

[RBM]

I don't know what the deal was with the original test, but the current tests were done by two different people, using the same lab, and a separate test is being done currently by someone else, using a different lab. I don't have the figures, but it was something like 10 times the acceptable level. I'm trying to determine if anything electrical, such as possible fault currents running through the system, could cause the problem

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[RBM]

[RBM]

Solder and brass which often contains 2% lead for free machining. here the water department adds lime which puts a layer between the lead and the water. Never prepare food with hot tap water. What kind of levels are you seeing? Pipe is cheaper than a few sleepless nights or disease.

The levels were high, and in this house it would be a huge job to replace the piping

[DanG]

Any pewter faucet sets - especially something old? I know many faucet sets had brass and solder fittings - saw them making them at the Delta plant before they moved to Mexico (won't buy Delta anymore). Even if the place still had lead sanitary, it shouldn't be able to cross anywhere. There just can't be all that much lead in old solder joints, but then, they have demanded going to the new stuff.

Just trying to think out loud with you.

[RBM]

Private well. I don't know the PH. I believe the reason for the current crop of tests, is to balance and neutralize the water, which is very hard. In doing the tests, they discovered the high lead levels, which they didn't realize they had. One of the testing companies suggested checking any electrical grounding on the system. I suppose if current is flowing through the piping, electrolysis would break down the lead

[gfretwell]

What is the pH? Well water or city?

[EXT]

Also if it is city water, what is the source of the city water, well, river, lake or a mixture?

I would test the water before filtering, immediately after filtering and then at the longest run faucet and compare what the differences are to narrow down the source. If you have lead in the water supply, I would suspect your filters are failing or letting water bypass the filter medium.

Re-piping doesn't have to be everything, basicaly the cold water in the kitchen, and bathroom faucets. A little or a lot of lead won't hurt the toilet(s), hot water that shouldn't be drunk or cooked with, and bathtubs/showers won't need to be changed. If it tests out to be the piping, bypass everything to supply the above only.

[HeyBub]

Look at the impellers on the pump. They may very well be crappy brass that is so eroded that it overwhelms the lead filtration system.

[RBM]

I have to get answers to all the new questions being asked. Their belief is that the lead is a new problem, and I'm not sure how they determined that

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[RBM]

The current crop of tests are being done as you describe. There is lead in the well, it's being removed by the filtering system, and then returns at high levels at the taps. Most of this piping is 30 years old, and from everything I'm reading, should have a layer of deposits covering the lead joints, and cause very little leaching

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[RBM]

The water tested lead free after the filtration system, then becomes contaminated in the internal piping system

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[bob haller]

bet the old test years ago was in error

PEX makes replumbing easy:)

just do the ones you drink

[Malcolm Hoar]

Assuming your test results are what they seem, I'd be looking at the faucets -- especially the one from which the tested water was drawn.

However, I wouldn't overlook the possibility that one of the lab tests produced a false positive (or negative). And I would certainly want independent confirmation before I started replacing a significant amount of piping!

[RBM]

bet the old test years ago was in error

PEX makes replumbing easy:)

just do the ones you drink

I have a sneaky suspicion that you're correct