BACTERIA IN DRINKING WATER: Are you at risk?
BACTERIA IN DRINKING WATER: Are you at risk?
By Susan Gallagher, Chief Naturalist Carbon County Environmental Education Center
The Times News, © 2001
Saturday, July 21, 2001
Bacteria. Think about that word long enough, and you’ll endup washing your hands.We tend to imagine bacteria as teeny little bugaboos,intent solely on causing us death and disease. The vision is no doubt responsible for an endless parade of anti-bacterial lotions, soaps, and cleaners across store shelves.
Since bacteria are the most common living thing on earth,covering nearly every earthly surface in a veil of unseen microbes, it’s a relief to know that only a small percentage of these “bugs” are harmful to us. In fact, without them, life as we know it would be impossible.
Bacteria in our intestines provide vitamin K, and some B vitamins; bacteria on the roots of certain plants take nitrogen from the air and “fix” it in the soil as a natural fertilizer; water-loving cyanobacteria use sunlight to grow, just as plants do, and serve as the base of aquatic food chains; other bacteria recycle dead and decaying matter back into the earth.
Biologists tell us that mitochondria and chloroplasts, energy producing cell bodies, began as free-living bacteria, and evolved into a relationship where they now serve as microscopic power generators for animal and plant cells, respectively.
Bacteria also aid in the production of cheese, yogurt, and vinegar. They help us develop new drugs, and even clean up oil spills.
Those are the good guys. The bad guys however, are responsible for some of the worst afflictions in human history. Even a partial list is enough to send anyone racing for the nearest available bottle of anti-bacterial hand sanitizer:
anthrax, botulism, cholera, diarrhea, diphtheria, leprosy, Lyme’s disease, plague, pneumonia, toxic shock syndrome, tuberculosis and typhoid fever, as well as sore throats and tooth decay.
Unfortunately, bacteria are one of the most common sources of well and spring water contamination in the U.S. Studies have shown greater than 40% of private water systems and over 70% of springs contain some level of bacterial contamination. So if water tests positive for bacteria, what does it mean for the average homeowner, who, with well and septic systems, is basically running a private water utility?
First it helps to understand how these tests are done. While identifying specific organisms in drinking water is expensive and time consuming, tests for total coliform bacteria, are quick, simple and cheap. Coliform bacteria are a relatively harmless group, but finding them in drinking water “raises a red flag”, and indicates the likely presence of more harmful bacteria.
Tests for fecal bacteria will show whether water has been contaminated with human or animal wastes. While more common than most of us would like to imagine, fecal contamination should come as no surprise. Modern “sanitary” plumbing systems have us intentionally pollute otherwise clean water with our own wastes, several times each day. As the wastewater is returned to our environment, it’s no wonder fecal bacteria can easily end up in well water.
Getting a negative test result doesn’t mean any well is forever free and clear of problems. Bacterial testing should be done at least annually, and is more likely to reveal contamination during the wetter months of late spring or early summer.
False positives can occur, and usually result from improper testing procedures. All test kit instructions should be followed carefully, so hands or some other source of bacteria don’t contaminate collection containers.
If a well is contaminated with bacteria, shock chlorination is the quick fix of choice. It involves use of the proper amount and type of chlorine to kill the bacteria present, followed by a thorough flushing of the system. But shock chlorination doesn’t address the source of contamination. It’s up to the homeowner to do that. Unlike many weighty environmental problems, addressing or preventing bacterial contamination can often take a simple, common-sense approach.
Beginning with proper well construction is a must. Leaky well casings, and poorly installed or maintained well caps can lead to contamination. Proper casings should extend upwards as the surrounding ground slopes away. This enlists the force of gravity in preventing possibly contaminated surface water from entering the well. Deeper wells also seem to be less susceptible to bacterial problems.
Keeping animal wastes from entering the well may be as simple as preventing animals’ easy access to the well casing. Don’t secure a dog’s leash to the casing for example. Do install a plastic screen cover on top of the casing, if needed to keep out curious rodents and their waste.
Regularly inspecting the septic system should be part of any plan for clean well water. Use septic systems only as directed, and have them cleaned as often as needed to remain problem-free. A system hooked up to a garbage disposal, or one supporting a larger household, will need to be checked and cleaned more often.
There can be some surprising sources of bacterial contamination, especially in areas where the geology and resulting water table levels are poorly considered. Inadequately planned cemeteries, or those without watertight caskets, for example, can lead to bacterial problems in nearby drinking water. Even animal burials should be done where the ground is high and dry, to prevent groundwater contamination.
The geology of an area alone may account for repeated or long term contamination by bacteria. One polluted well, located in just the right – or in this case, wrong – location, can pollute other wells some distance away.
Equally surprising is the fact that sludge, wastewater, and manure applications to farm fields, when done properly, causes few or no problems.
Some with long term bacteria problems in the well become complacent, continuing to drink contaminated water, since they’ve “… never gotten sick before”. Repeated exposure to some harmful bacteria can lead to immunity. This is why the native populations of some foreign countries can drink the same water that leaves tourists with days of dysentery. But the kinds and numbers of bacteria present in a well can change dramatically over time. Our immune systems can fluctuate as well, and water that doesn’t cause illness one day, may easily do so the next. Visiting friends and grandchildren may also be adversely affected by well water that causes no problems for the homeowner.
Overall, its clear we can harbor little hope to win any wars against bacteria. They are the oldest known organisms on earth, dating back roughly 3.5 billion years. They are able to live almost everywhere, under even the worst conditions. We share our world – share our bodies – with them. They help us and hinder us in untold ways. But if we’re careful, they need not contaminate even one precious drop of drinking water.
The Carbon County Groundwater Guardians can arrange for well water testing at reduced costs through Wilkes University.