Free Encyclopedia of Building & Environmental Inspection, Testing, Diagnosis, Repair
Ask a Question or Search InspectAPedia
InspectAPedia ® Home
WATER PUMPS, TANKS, TESTS, WELLS, REPAIRS
WATER CONTAMINANT LEVELS
WATER HAMMER NOISE DIAGNOSE & CURE
WATER ODORS, CAUSE CURE
WATER PUMP REPAIR GUIDE
WATER PRESSURE LOSS DIAGNOSIS & REPAIR
WATER PUMP SHORT CYCLING
WATER SOFTENERS & CONDITIONERS
WATER TANK REPAIR PROCEDURES
WATER TANK: USES, TROUBLESHOOTING
WATER TESTS, CONTAMINANTS, TREATMENT
WATER TREATMENT EQUIPMENT CHOICES
WELLS CISTERNS & SPRINGS
WELL FLOW RATE
WELL WATER PRESSURE DIAGNOSIS
WELL YIELD IMPROVEMENT
WINTERIZE A BUILDING
Water tests for lead contamination: what drinking water contamination tests should you order? This article explains the general classes of water contaminants covered in a water test for lead.
There are several possible sources of lead in drinking water, including lead in ground water, lead contamination from municipal water piping, lead contamination from building water supply piping or fixtures, well contamination by lead from surface contamination due to lead paint chips, and insignificant lead contamination from lead in well pumps or faucet parts.
This website describes the types of water testing available, outlines common water test fees, describes the details of what parameters are included in various water test options, and gives advice to assist you in deciding what tests to order. For help tracking down sources of lead contamination in & around homes see LEAD POISONING HAZARDS GUIDE.
Green links show where you are. © Copyright 2013 InspectAPedia.com, All Rights Reserved. Author Daniel Friedman.
Lead Contamination from Water Supply Lines/Entry Mains, Lead Testing & Correcting Contamination from - Lead Pipe Problems/Advice
Depending on the duration and extent of lead-water contact, lead can enter the water supply if lead is present in supply piping or fixtures. Common sources of lead in water supply piping include older lead-bearing solder used on copper pipes, possible lead content in brass piping or fixtures, lead water supply piping (rare), and lead water supply entry main between a building and the public water main in the street (common in some areas).
Recently there was also a flurry of concern about lead contributed by brass in private well pumps. However the testing methods used for this latter topic misrepresented an exaggerated and frankly dubious risk. Finally, it is possible for lead to be found in private well water if lead contaminants have entered the local aquifer.
New York State Department of Health has set an action level of 0.015 mg/L of lead in a sample of water drawn from a tap used for drinking water after a 6-hour period of no water use.
Lead levels will usually be quite high in water which has sat overnight in a lead line from street main to house.
Most lab tests indicate low lead levels in water from such lines after the test fixture has run until all standing water in the piping has been flushed out with fresh from the municipal supply mains in the street.
There are ambiguities in instructions offered by some municipalities about how to obtain a water sample for lead testing. The particulars of how the water sample is taken can make a big difference in the lead level obtained. Our photo (below) shows how to recognize lead water supply piping between a building water shutoff valve (or water meter) and the water supply mains in the street. The author is pointing to the wide lead wipe joint connecting the lead water pipe to the bronze bottom of the water shutoff valve.
Most local building codes do not require removal of lead, for example, the City of Poughkeepsie Building Codes do not require removal of residential lead supply lines (house to street). However eventually (usually after 40-60 years) these lines corrode, leak, and have to be replaced. Replacing the main supply from street to the water meter, when required, could involve significant expense.
People with concerns for the amount of lead in water should consult the local health department and should have their water tested for lead. Typical lab fees are $20. to $25. per sample plus the cost of hiring an independent consultant to collect and handle the water sample if you don't do it yourself.
Even if you are not concerned with testing for lead in water it would be wise to reduce possible lead intake by flushing any lead-containing piping before drinking such water. In addition, lead-in-water removal equipment is available from water treatment companies.
If you need to calculate the amount of water to run out of piping to be sure you are obtaining water from the street, that is, the volume of gallons of water inside of water piping, you need to know simply the length and diameter of water piping between the faucet where the water test is to be taken and the location whose water you want to test.
For example, let's say the water contained overnight in the water main in your street is what we want to test.
1/2" internal diameter water piping contains about 0.01 gallons per linear foot;
3/4" ID piping contains about 0.02 gallons per linear foot, and
1" water piping contains about 0.04 gallons per linear foot.
Just measure or estimate the number of linear feet of water piping of each diameter to perform this calculation.
Alternative worst-case lead in water test procedure
If we run water at a building tap until the water temperature first feels cold and immediately collect our water sample, we are most likely collecting and testing water that has been sitting in the water service piping between the building and the street water main.
See How Much Water is In the Well? for a detailed explanation of how to calculate the volume of water inside of pipes.
Also see our review of a Home Test Kit for Lead in on building surfaces located at LEAD TEST KIT for HOME USE. The same company offers a lead-in-water test, as do local health departments and private water testing labs in most cities. Also see Lead Contamination in Drinking Water: Testing & Correction - Advice.
Frequently Asked Questions (FAQs)
Questions & answers or comments about testing well water or drinking water for lead contamination.
Ask a Question or Enter Search Terms in the InspectApedia search box just below.
Technical Reviewers & References
Related Topics, found near the top of this page suggest articles closely related to this one.