Water Testing Results

If you ordered water quality testing, like coliform or lead, you may have trouble deciphering the lab report. While we’ve tried to explain things on your report, you may have other questions about what your sample results mean.


This is the most common test used to determine if water is safe to drink. There are 2 tests in a Coliform sample result: Coliform, and e. Coli.

If your water tests positive for coliform, it doesn’t necessarily mean it will make you sick. Coliform is a family of bacteria. They are used to determine if something is getting into the water. A positive result on coliform could mean the water is stagnant, or there might be a break in a pipeline, or it could even be caused by turning on canal water in the spring.

If your water tests positive for e. Coli, it is not safe to drink. The water should be treated before it’s used.


If a coliform test comes back positive, the well can be disinfected/flushed/resampled. That’s something we can do as a service, or we can walk you through the steps. Rarely, it can take 2 disinfections to clean up a well.

Water can be treated by boiling. Fill a pot and put it on the stove on high heat until it reaches a full rolling boil. Keep boiling it for at least 1 minute. Then, turn the heat off and allow the water to cool completely. You can use it for anything, or store it in an airtight container.

You can use disinfectants to treat water. Household chlorine bleach can be used to disinfect water. Use a 6% solution of bleach, and add about 8 drops per gallon of water. Use 1/4 teaspoon for 4 gallons of water.

You can use a filter to remove contaminants from your water. Some camping stores sell water filters that you can use to treat water. Or, you can install a Reverse Osmosis system to remove contaminants from your water. An RO system has a membrane cartridge that will need to be replaced about once a year.

You can use an ultraviolet (UV) disinfection system to treat the water. A UV system passes the water through a tube that hits it with ultraviolet light. The UV light deactivates any bacteria in the water. UV systems are a good solution, but the bulbs have to be replaced about once a year.


Some areas of Idaho have natural underground deposits of Arsenic metal. This Arsenic leaches out into the water, and can cause health problems in people who drink it.

The maximum limit for Arsenic is 0.010 mg/L – or 10 parts per billion. If your water has more than that, it could lead to a higher risk of certain kinds of cancer.


If your water has arsenic, you can treat it by installing a device that can remove arsenic from the water.

An RO system is probably the least expensive option for removing arsenic.

Alternately, there are some other kinds of treatment systems that use special pellets that bind up the arsenic in the water.

Boiling will not remove arsenic from your water.

Nitrate and Nitrite

Nitrates are byproducts of animals and plants. Fertilizer and dairy / agricultural waste are two of the main sources for Nitrate and Nitrite. If you live near a dairy or a farm, you might want to test for Nitrates.

(Some foods use Nitrates as a preservative – these are unrelated to drinking water.)

The maximum limit for Nitrates is 10 mg/L – or 10 parts per million. If you have a higher level than this, it can lead to blood-oxygen health problems like blue-baby syndrome.

The maximum limit for Nitrites is 1 mg/L – or 1 part per million. Health effects are similar to Nitrate, and Nitrites can be converted to Nitrates in the body.


Treatment for Nitrates is similar to that of Arsenic. Reverse-Osmosis treatment equipment is sufficient.

Boiling will not remove nitrates or nitrites from your water.

(Note: We very, very rarely see Nitrites in Idaho groundwater.)


Lead is a metal that was used in pipes and plumbing. If your house was built after 1986, it is unlikely that you have any lead fixtures in your house. Lead can leach out of plumbing and into your drinking water.

Lead almost never exists naturally in a form that enters drinking water.

The EPA maximum limit for lead is 0.015 mg/L – or 15 parts per billion. However, any lead in your drinking water is cause for concern. Lead in drinking water can cause brain function and brain development issues, especially in children.


Like Arsenic and Nitrate, a Reverse Osmosis system can be used to remove lead from drinking water.

It is also recommended that lead pipes and fittings be replaced.

For more information

If you have any questions or need further information, please contact us.