WICHITA, Kansas ? About 150,000 people in Kansas get their drinking water from private wells.
How clean, and safe, is that water? Short answer: It depends.
But new research suggests those wells deliver water tainted with a range of pollutants. Some leaked from dry cleaning operations. Yet far more wells soak up, and deliver to taps, fertilizer that?s been building up in Kansas soil and water over generations of modern farming.
But it?s not up to regulators from Washington or agencies in Topeka to test private well water quality. That falls to individual well owners. With little to no government oversight, some public health officials worry that?s creating a system where far too many people are left vulnerable to potential cancer-causing pollutants and toxins.
New research from Kansas State University shows that groundwater quality in the Great Bend Aquifer in south-central Kansas rates far worse today than 30 years ago.
The main culprit is a dramatic increase in the amount of nitrate. It?s a byproduct of the Green Revolution of the 1960s that turbo-charged modern farming toward greater yields, especially the use of chemical fertilizers.
Farmers learned that soil laced with extra nitrogen could squeeze more bushels from an acre of land. But not all that nitrogen stays put or gets absorbed in wheat, corn, sorghum and soybeans. Some runs off into streams, or trickles into underground reservoirs.
?The change that we see is comparable to the most extreme change measured by a nationwide study,? Matthew Kirk, associate professor of geology at Kansas State University, said. ?So this is a pretty big increase in nitrate.?
High levels of nitrogen in water can lead to shortness of breath. It can even cause death in young children and older adults. The federal Safe Drinking Water Act, which only governs public drinking water, limits nitrate levels to less than 10 milligrams per liter.
When Kirk sampled the water for his research, seven of the 22 wells tested exceeded that limit.
When analyzing the molecules, Kirk said it was clear that the nitrogen was coming from fertilizer leaching into the aquifer from the surface. This particular part of the natural underground reservoir is more vulnerable to land use changes because it?s relatively close to the surface, so the water doesn?t get filtered well. Kirk said it could stand as an early warning for other deeper parts of the broader High Plains Aquifer.
Kirk said private well users need to test their water regularly or put the health of their families at risk.
?We do that for municipal water supplies. But for rural well owners, it?s entirely up to them,? he said. ?They don?t have to have their water tested unless they want to.?
Because there?s no reporting requirement, there?s also no statewide record of groundwater quality. And even if collecting that kind of data helped officials understand the bigger picture, the movement of water underground is complex. Just because one well is contaminated doesn?t mean the next well over is too.
The National Ground Water Association recommends private well owners do a basic quality test for bacteria and nitrates once a year.
