In Virginia 34% of the population is estimated to obtain their drinking water from private groundwater wells, more than twice the national average. If you have your own well, then the responsibility for ensuring that your family and friends are drinking safe water rests with you. Just because your water appears clear doesn’t necessarily mean it is safe to drink. You cannot taste bacterial contamination from human and animal waste, nor nitrate/ nitrite contamination. Many chemical contaminants cannot be tasted or smelled at levels that can impact your health. Since bacterial contamination cannot be detected by taste, smell, or sight, all drinking water wells should be tested at least annually for Coliform bacteria and E Coli. Testing is the only way to detect contamination in your water. Testing is not mandatory, but should be done to ensure your family’s safety.
The quality of your water will be determined of the source of the groundwater, the ability of your local geology to protect or impact your aquifer and the absence or presence of a potential local source of contamination. First of all let me say that according to the US EPA actual events of groundwater contamination have historically been rare and typically do not occur at levels likely to pose significant health concerns. This fact is the basis of the EPA and state health departments’ acceptance of private and unmonitored use of groundwater for drinking water purposes for a significant portion of the United States. However, as population density increases and we use more and more chemicals, pesticides and drugs, there are more opportunities to contaminate our groundwater. Because I am a retired environmental engineer I tend to focus on threats to the groundwater and worry about my groundwater quality more than most.
The most common sources of pollution to groundwater supplies come from two categories; naturally occurring ones and those caused by human activities. Naturally occurring contamination are produced from the underlying soil and rock geology. Microorganisms in the soil can travel into groundwater supplies through cracks, fissures, and other pathways. Nitrates and nitrites from the nitrogen compounds in the soil can also enter the groundwater. From the underlying rocks radionuclides and heavy metals can enter the groundwater. There are areas with natural occurring arsenic, cadmium, chromium, lead, selenium and fluoride. While many natural contaminants such as iron, sulfate, and manganese are not considered serious health hazards, they can give drinking water an unpleasant taste, odor, or color.
Human activities can also introduce contaminants into the groundwater. Bacteria and nitrates can be caused by human and animal waste. Improperly constructed and sealed wells can allow surface contamination to enter the well. Improperly maintained septic systems containing human waste and any chemical you flush down the drain, horses, and backyard poultry can contaminate the groundwater. Leaks from underground storage tanks, surface disposal of solvents, motor oil, paint, paint thinner, or nearby or historic landfills or industrial operations can contaminate groundwater. A confining geological layer can protect groundwater from surface contaminants more effectively than a fractured rock system, and there is very limited natural protection in karst terrain. So in Virginia, where there are rich supplies of groundwater our aquifers can be very susceptible to contamination.
If you have a perceived water problem with taste or quality, have your water analyzed. Though it is cost prohibitive to test for every potential contaminant, a broad baseline analysis should be performed occasionally (every few years). The cheapest way to do this is a commercial product aimed at the private homeowner. One product I have used is the WaterCheck with Pesticides. This product covers 15 heavy metals, 5 inorganic chemicals, 5 physical factors (like hardness and pH), 4 trihalo methanes, 43 volatile organic chemicals (solvents), and 20 pesticides, herbicides and PCB’s. The product is sold by an EPA certified laboratory that is also certified in Virginia, National Testing Labs. The Minimum Detection Levels, which are the lowest levels at which the laboratory detects that contaminant are below the levels established by the Safe Drinking Water Act so this relatively affordable ($217 including shipping and handling) test will serve as a broad screen of drinking water. Though I know it is tempting to skip the full analysis, don’t. Analysis is the only way to fully know your groundwater aquifer. Once you know the characteristic of your water, they are unlikely to change quickly and you can monitory the safety of your water with the far more affordable home testing kits. Having a good analysis allows you to choose the proper treatment system or plan of treatment.
In the March 2012 Good Housekeeping magazine they had an extensive article on water. One of the things they did was to evaluate home water testing kits. To test the home contaminant-detection kits, the Good Housekeeping Research Institute worked with the Water Sciences Laboratory at the University of Nebraska at Lincoln. Lab researchers spiked water samples with measured concentrations of contaminants the kits claimed to be able to detect, including two herbicides, nitrate, copper, lead, and bacteria. Then after following the kit's instructions, evaluated its performance at detecting the known contaminants. They found the PurTest kit to be the most accurate and easiest to use, but the second ranked First Alert test kit was also good and significantly cheaper.
PurTest Home Water Analysis, Model P33, $40: With an overall detection accuracy of 10 of 12, it measured iron and alkalinity too high. It was also the easiest kit to use. The kit tested water for: atrazine, simazine, nitrate, nitrite, total chlorine, pH, total alkalinity, hardness, e-coli, lead, copper, iron, but inaccurately measured both iron and total alkalinity. The kit was found to be very easy to use and had duplicate test strips for everything but the bacteria tests.
First Alert Drinking Water Test, Model WT1, $17: With an overall detection accuracy of 8 of 9, it missed total chlorine. The kit claims to test for: atrazine, simazine, nitrate, nitrite, total chlorine, pH, hardness, lead, e-coli. This kit missed identifying chlorine. No duplicate strips were provided for most of the tests.
These test kits allow the home owner to inexpensively test their own water on a regular basis to make sure that they meet the most basic potability standards and monitor for any changes in water quality. If you need help in understanding your water test results you can contact the Virginia Master Well Owner Network (VAMWON), an organization of trained volunteers and extension agents dedicated to promoting the proper construction, maintenance, and management of private water systems (wells, springs, and cisterns) in Virginia. The Cooperative Extension Services in Virginia manages the program and have numerous publications and fact sheets that can help homeowners make educated decisions about their drinking water. The VAMWON volunteer or Agent can help you identify problems with the water system and provide information on suggested treatments options and other solutions. You can find your VAMWON volunteer neighbor through this link by entering your county in the search box.
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