Testing Your Residential Well Water
People who drink water from wells and other nonpublic sources should test their water routinely to make sure it is safe to drink. If a water company supplies your water, they can usually give you information about its quality.
If you are testing the water because of illness in your family, you should contact your physician first and test the water based on his or her recommendations. If you are testing the water because you suspect a problem with your pets or livestock, we recommend that you contact a veterinarian or agricultural extension agent for advice.
If you need a water test as part of a mortgage or refinance, we’ll need to know specifically which tests are required and if it is acceptable for you to collect your own sample. We do not collect residential water samples.
If you are testing your water at the request of the PA DEP or the Department of Agriculture, we need to know what analyses you must perform and additional information about your system.
Many of the other things we can test for on residential well samples are not considered by the EPA to be directly health threatening. Therefore we recommend that you only test for things like iron or hardness if you are having specific problems such as staining or odors. Because the character of water can vary from well to well we recommend that you discuss any specific problems with a water treatment professional to determine appropriate testing.
Please view the information below to help determine the type of testing you’ll need to perform.
- Testing Your Water for Bacteria
- Testing Your Water for Nitrates
- Testing Your Water for Lead
- Other Tests You May Want
- Testing at the Request of the PA DEP or the Department of Agriculture
- Instructions for Disinfecting your well
- Directions and Business Hours
Testing Your Water for Bacteria
All well owners should test for coliform bacteria every 6 months to 1 year. This analysis will let you know if your water is bacteriologically safe to drink. Coliforms themselves usually do not make people sick but their presence indicates a potential for more harmful organisms to be present. Symptoms caused by these organisms are usually flu-like (diarrhea, vomiting and other forms of gastrointestinal distress.) Even if you do not have any symptoms it is important that you don’t drink the water until it is shown to be safe.
To test your water for bacteria, you will need a special sample container and instructions, which you can pick up from Eurofins Lancaster Laboratories Environmental free of charge. There is a fee for the test. Please call us at 717-656-2300 and ask to speak with someone in our Environmental Client Services Group to learn about the fees associated with this test.
Your report should be mailed to you in about 1 week. We normally report presence/absence for both Total Coliform and e.coli. If you need an actual count the fee is higher and you must request this when you drop off your sample.
If your well is new, if you have had work done on your plumbing recently or if the well has not been used for a month or more, we recommend that you disinfect your well prior to testing.
Testing Your Water for Nitrates
Wells in Lancaster County and other agricultural areas often contain nitrates above the allowable level of 10 mg/l. High nitrates are considered a health concern for infants less than 6 months of age, pregnant women and nursing mothers, so most people need not be concerned. Removal of nitrates can be expensive and therefore it is often easier to use bottled water until the baby is older than 6 months. People in Lancaster County who want to subdivide are often asked to test for nitrates. If this is the case, you need to find out how many samples you need and whether or not you can collect them yourself.
To test for nitrates, you will need special containers (small vials, one of which has a preservative in it) and instructions. You can pick up these containers at Eurofins Lancaster Laboratories Environmental at no charge. There is a for the test. Please call us at 717-656-2300 and ask to speak with someone in our Environmental Client Services Group to learn about the fees associated with this test.
Your report should be mailed to you in about 2 weeks.
Testing Your Water for Lead
A potential health concern is high lead content. While it is rare for lead to occur naturally in well water, it can leach from lead pipes, solder or fixtures. If your home is older or you have other reasons to believe your water contains lead you should consider having it tested.
You can use your own clean container to test for lead. We require 1 liter of water, which is about a quart. In order to find the “worst case” level of lead in your water you should select a tap from which you commonly drink, run the cold water for about 10 minutes and then not use the water for at least 6 hours. After 6 hours, collect the sample directly into the bottle without letting the water run. Your report should be mailed to you in about 2 weeks. Please call us at 717-656-2300 and ask to speak with someone in our Environmental Client Services Group to learn about the fees associated with this test.
Other Tests You May Want
If you have a list of other tests you would like to have run on your water you may need special containers or instructions. Please call us at 717-656-2300 and ask to speak with someone in our Environmental Client Services Group.
Testing At the Request of the PA DEP or the Department of Agriculture
Testing at the request of the Pennsylvania DEP or department of agriculture
If the Department of Agriculture is asking you to test your water you probably need to test for coliform bacteria. (Click here for more information). We recommend that you check with them to be certain there is nothing else they need.
If PA DEP is asking you to test your water we need to know specifically what they require. If you are testing as a public water supply, we also need to know your PWSID number and entry point number for reporting purposes. Once you have this information, please call us at 717-656-2300 and ask to speak with someone in our Environmental Client Services group.
Instructions for Disinfecting Your Well
If you would like to disinfect your well, please do the following. It is critical that each step be performed properly:
Mix 1/2 gallon of household bleach (such as Clorox) in a bucket of water and pour it into the well.
Attach a hose to a tap beyond the pressure tank and run the water into the well for about 15 minutes. This circulates the bleach through the well.
Open all the cold water taps in the house and allow the water to run until you smell chlorine at each tap. This usually takes about 30 minutes.
Turn off the water and let it sit in the plumbing for at least 3 hours, preferably overnight.
You can then run the water at each individual tap until the strong chlorine odor is gone and then use the water as you normally would. The water should not be tested until all the chlorine is gone, which can take anywhere from 10 to 20 total hours of running time. You can run the water off more quickly by attaching a hose and draining the water outside, but you will get the truest indication if the disinfection was effective by waiting 2 to 3 weeks to retest. If you water still tests positive you should contact a plumber to discuss treatment options.