DOMESTIC WATER TESTING
Homeowners on a private well should test their drinking water annually. Water samples must be collected in special laboratory bottles. Bottles for several labs in the area are available at the Gallatin Local Water Quality District. The bottles are free and available at these locations:
Gallatin Local Water Quality District
215 W. Mendenhall, Suite 300
Environmental Health Services
215 W. Mendenhall, Room 108
You can have your water tested for a discount by participating in the Well Educated Program. Click here for details.
WHAT TO TEST FOR
- It is recommended that you test your water on an annual basis for total coliform bacteria and nitrates. A more comprehensive test to categorize your overall water quality that includes parameters such as pH and hardness, specific conductivity and metals (calcium, magnesium, sodium, potassium, manganese, iron, copper, lead and arsenic) can be done every five years. This is called a full domestic analysis.
- A pesticide/herbicide screening test may be recommended if you live in an area with a history of heavy pesticide or herbicide use. Because this test is usually done as a "screen", the level of detection for the test may not be sensitive enough to pick up a specific problem. If you know the name of the pesticide or herbicide you are concerned about, a test can usually be run to analyze for it specifically. Discuss these issues directly with the lab you plan to have analyze your water sample. You will need to contact the laboratory in advance of this type of testing because special sample bottles are required and must be provided by the laboratory.
- If you live in an area with known high levels of arsenic or lead, you may want to test for this parameter on a yearly basis rather than every 5 years.
- If you notice a change in taste, odor or color in your well water, consider having your water tested for metals.
- If you have your well serviced or if there has been a flood in your area you should consider having your water tested for total coliform bacteria and nitrates.
COLLECTING A WATER SAMPLE
Bacteria Sampling Procedure
Well Disinfection Procedures
General Sampling Procedure
- Select a convenient sampling point at a faucet. An outdoor faucet closest to the well is preferred. Remember, if you have a water softener or treatment system installed at your home, the water sample must be collected before it goes through these systems.
- Remove any screen or aerator from your faucet.
- Run the cold water faucet for at least 20 minutes at a high flow rate before collecting the sample. This is critical! This flushing is done to clear water that has been standing in the pipes and pressure tank and bring in "fresh" water from the well before sampling. Incomplete flushing may result in an inaccurate measurement in the laboratory.
- Without turning the faucet off, reduce the flow rate at the faucet and open the sample bottle. Be sure not to touch the inside of the sample bottle or lid.
- Fill the sample bottle and replace the cap. Make sure the cap is on tight.
- Refrigerate the sample until you take it to the lab. Transport the sample in a cooler to the lab. Remember, some tests have holding time limits for analysis, so you should get the sample to the testing laboratory as soon as possible after collecting it for best results.
Volatile Organic Chemicals Sampling Procedure
Collect the sample ONLY in the glass vial provided by the laboratory. Follow these additional steps:
- Reduce water flow to prevent excess air in the sample.
- Fill the sample bottle to almost overflowing to remove all air from the bottle.
Pesticide, Herbicide and Petroleum Sampling Procedure
Samples for pesticide testing must be taken so they will not deteriorate or become contaminated before reaching the lab. Contact the lab testing your sample for complete instructions and a collection kit. Collect sample ONLY in the amber-colored bottle provided. Dark glass prevents light from degrading the sample. Specific steps needed when testing for pesticides include:
- DO NOT RINSE the sample container! It contains a preservative necessary for proper analysis of your sample.
- Take the sample from a COLD water tap indoors. Do not take samples from a hose.
- Remove the faucet aerator.
- Allow the water to run for 3-4 minutes before sampling.
- Fill the container full to the neck and cap tightly with the Teflon-coated lid provided by the lab. This special lid prevents false positive results caused by certain plastics.
- Keep the sample refrigerated and submit to the lab within 48 hours. If shipping the sample, pack the sample in ice and ship in a styrofoam or other insulated container. Many laboratories will provide ice packs and shipping container for you.
For more information, contact the Gallatin Local Water Quality District at 582-3148 or email us.