August 27, 2014 - Bacteria and nitrate are widespread in the environment, so every household water well owner should regularly test the water to make sure no health risks exist, the National Ground Water Association recommended today.
While most bacteria found in water do not cause disease, disease-causing bacteria called pathogens can exist in well water given the right circumstances, NGWA said. Nitrate is not uncommon to rural areas due to its use in fertilizers and because it's sometimes linked to animal or human waste.
"We recommend that well owners test their water annually for bacteria and nitrate because of their widespread presence," said Cliff Treyens, NGWA public awareness director. "Knowing whether or not you have a problem with bacteria or nitrate through valid laboratory testing is key to keeping your water safe."
Bacteria: Coliforms are bacteria that occur naturally in the environment and may indicate the possibility of pathogens. Fecal coliform and E. coli are bacteria whose presence indicates that water may be contaminated by human or animal waste harmful to human health. Pathogens can cause diarrhea, cramps, nausea, and headaches. In the extreme, they can be lethal.
Potential sources of bacteria include:
- Runoff from woodlands, pastures, and feedlots
- Septic tanks and sewage plants
- Animals, both domestic and wild
Potential pathways of bacteria into well water include:
- Reduced pressure or suction in water lines that draw soil water at the pipe joints
- Faulty sanitary seals in a well system, i.e., a faulty well cap, grout, pitless adapter
If test results indicate the presence of bacteria in your well water, a qualified water well system professional should determine whether there is a cause or source for the bacteria entering the well. Any necessary maintenance should be performed and the well system disinfected by the professional.
Nitrate: The largest source of nitrates are fertilizers used on crops. Animal and human waste contains nitrogen in the form of ammonia. Nitrate also is generated by:
- Decomposing plant and animal materials
- Septic systems
- Industrial effluent
The greatest health concern from nitrate is "blue baby syndrome" or methemoglobinemia. The syndrome is seen most often in infants exposed to nitrates from drinking water used in baby formula. Infants ages 0 to 3 months are at highest risk. The syndrome affects the ability of the baby's blood to carry oxygen to body tissues.
The U.S. Environmental Protection Agency has a maximum contaminant level for nitrate of 10 parts per million (milligrams per liter) as nitrogen.
The EPA has approved certain methods for removing nitrates including reverse osmosis and ion exchange. Reverse osmosis works best on point-of-use systems, which generally are used in places such as the kitchen sink where water is used mostly for drinking and cooking. Ion exchange, along with a water softening system, can provide a whole-house solution for nitrate contamination.
To learn more about water well and groundwater stewardship visit WellOwner.org.