It may come as a surprise to some that the measurements of nitrogen levels in the Raccoon River are extremely high. The result is that the drinking water for the Greater Des Moines area (about 500,000 customers) costs more because Des Moines Water Works must reduce the levels before you and I can drink the water.
The US EPA has established a maximum of 10 milligrams per liter for nitrogen in the form of nitrate, the more stable and more threatening form of nitrogen in water. (10 mg/l is the same as 10 parts per million, or ppm). Above that level, infants under six months of age are at risk for “blue baby syndrome” and shortness of breath. See this EPA web page for more: http://water.epa.gov/…/contami…/basicinformation/nitrate.cfm
The surprise isn't that nitrate levels are high – it's happened before – but that the levels are over the EPA standard in the wintertime. Usually late fall and winter see very low nitrogen levels.
What's different this year? We had an exceptionally wet summer, with numerous storms and large dumps of rainwater. Undoubtedly the groundwater – the water that seeps into the soil – has risen to unusual highs (called the “high water table”). Groundwater doesn't sit in place but flows sideways toward the path of least resistance, once it has hit a barrier: dense clay or impermeable bedrock. We have both in Iowa, but mostly thick clay, often close to the surface.
So groundwater flows sideways, more often than not downhill, and into our streams. You can see the result easily: many rivers are higher for this time of year than is typical because they are “recharged” by the groundwater.
Add to this natural, normal occurrence several unnatural factors: tile drainage systems in cropland, removal of topsoil down to the denser clay in developed areas, and alterations of the land surface to speed the flow of surface and groundwater to the rivers. Because nitrate is water soluble, all that water carries any excess nitrogen with it.
There you have it. Late summer rains, groundwater near capacity, “recharging rivers,” tiled fields, altered landscapes. It's a “perfect storm” to create the high nitrogen levels we are seeing, and to read how Water Works must use its nitrate filtration systems to keep us safe.
Why don't regulating agencies do anything about it? Because they are pressured by political interests to ignore the problems (that is, to not enforce existing rules), do nothing about the problems (kick the can down the road, if you will, in a social climate of “deregulation”), or avoid the most damning means of establishing that the problem exists: measure it.
I've been out in central Iowa streams during springtime high-nitrate flushes, when the reading was somewhere between 20 and 50 ppm. That's enough to cause headaches for any drinking water system that uses river water. (By the way, a reading between 20 and 50 automatically is recorded as “20,” at least by citizen water monitors, even though I've seen readings that likely were in the 40s.
What's to be done? In my mind, blaming “farmers” is problematic. What, exactly, is a “farmer”? A grain-and-livestock operation that ekes out a living on 600 acres? Or a series of animal confinements managed by one person, the design and operation of which is dictated by one of the few large livestock processing companies? What about the farmer-operators who manage a few tens of thousands of hogs in several facilities and crop several thousand acres? Or the absentee landlords who rely on renter-farmers to manage something for which the renter may not have much responsibility?
Solving the problem of nitrogen levels may begin in several ways. Measurement, followed by enforcement, is a must. Redefining “farmer” more precisely is another, so that the term does not provide cover for large agribusinesses and absentee landlords. Until we look at this problem with greater care and more insight, the word games of the ag lobby groups and their almost hand-picked politicians will assure that the costs are passed onto we, the people who live downstream.
7 Comments
Nitrates in Iowa's Waters
Des Moines can’t be the only community facing this problem. It would be interesting to see a study of all water works in Iowa to discover the extent of the cost to users. Previously it has been reported that the Des Moines Water Works (DMWW) dumps the nitrate once extracted into a surface lagoon that has in the past been washed on down stream to be extracted by another municipality for their consumption or it heads down to the dead zone.
I live in rural Dallas County. There is a confinement recently constructed next to my home. In the manure management plan, they indicate the fields that will receive the animal waste. Within the past month, those fields have been grid tiled because they held surface water much of the summer in spots. The tiling systems accelerate the removal of surface water to the watershed flow. this particular watershed feeds Walnut Creek which ends up at DMWW. Perhaps DMWW should name accomplices in their suit.
ewessels Tue 23 Dec 8:25 AM
great diary
Your comments about the “word ames of the ag lobby groups” reminded me of this article from last week:
desmoinesdem Tue 23 Dec 8:55 AM
good diary
The diary does a good job of describing how the confluence of climate, agriculture, environmental and business interests are impacting the source water hitting DMWW. I think it’s also important to point out that the concentration of individual flushes is becoming more and more concentrated.
Heavy tiling and farming of more marginal ground (without sufficient buffer or filtering) is making these flushes much more concentrated and harder to predict. These same practices are also increasing risks and impacts from flash flooding.
mark-langgin Tue 23 Dec 9:01 AM
observation
perhaps the assertion “To Farm Bureau assertions that excessive rainfall caused it, Stowe retorts, “Water transports nitrates. It doesn’t make them.” would be more clear if we consider WHO puts those nitrates on the field in the first place.
abgdinstr Wed 24 Dec 9:14 AM
poop on ice
I saw a nearby factory farm pumping this untreated sewage from the lagoons below the confinement and “dumping” it onto the frozen ground down the road a ways. Normally they would inject it into the ground, but with the quick and early freeze they are left to just unload it anyway they can. In most cases this means “pretending” to inject it, while in fact spreading it on the surface.
The particular field is not untypical of Iowa in that it has a couple drainage areas that ran through it. The sewage was dumped right over them, although the manure management pan for this field indicates they would avoid the actual drainage.
Of course, with any sort of precipitation the sewage runs right into the creeks anyway, but with this combination of frozen ground and a desperate need to get rid of all this toxic waste, its no wonder its getting drained in to the Des Moines drinking water.
thamnophis Wed 24 Dec 9:12 PM
More health effects of nitrates
First a quick correction to the post. There are 1,000 milliliters in a liter of water. 10 milliliters per liter of water is 10/1,000 or 1/100 or 1%. When nitrates hit 1%, they exceed the EPA limit.
The 10 milliliter threshold for nitrates is higher than other counties. There are medical studies that show 5 milliliters of nitrates in a liter of water can trigger other health problems. The most common are stomach cancer, thyroid cancer and ovarian cancer in post-menopausal women. Plus the well documented “blue baby” syndrome.
The U.S. Geological Survey (USGS) takes daily water readings around the country. Here is their link to real time data for Iowa: http://waterdata.usgs.gov/ia/n… After reading the nitrate levels in Iowa rivers for the last month, I am very concerned that the nitrate problem is getting worse, not better.
We do need to revise how we talk about and regulate farmers. I propose that we have three classifications: 1) Homestead farms that are up to 400 acres; 2) Commercial farms (what we think of as family farmers today) of up to 2,000 acres, and 3) Industrial farms, those over 2,000 acres. Livestock farms would be classified similarly. Homestead farms would be largely exempt from regulation, commercial farms would face some regulation, while industrial farms would be the most closely monitored and regulated.
It is a know fact that nitrogen is water soluble and the more nitrogen present when rain or snow falls, the more nitrates that end up in our rivers and streams. That may mean that we have to end fall application of nitrogen. My high school chemistry teacher cussed me out for applying anhydrous ammonia on our family farm in the fall. She pointed out that at least a third of that nitrogen would be gone by spring (Hello Raccoon River). It may also mean more testing of farm drain tile lines, with corresponding reductions in nitrogen fertilizer application or multiple small split applications during the growing season.
The bottom line question we have to ask as Iowans is how many infants do we want to die of blue baby syndrome, much stomach cancer, thyroid cancer and ovarian cancer do we want to deal with to grow more $3.00 corn?
Remember when the coal companies in West Virginia poisoned the water of 300,000 people with toxic chemicals. Their response was that toxic chemicals and poisoned water was the tradeoff for coal jobs. Do you remember thinking or even saying “No, being poisoned is not a fair or even a necessary tradeoff for coal jobs.”
Now ask yourself, is Iowa like West Virginia? Are we going to accept being poisoned by a few bad apples among the 90,000 farmers in Iowa so that we can grow more cheap corn?
tom-fiegen Fri 26 Dec 12:29 AM
I stand corrected
Nitrates are reported as milligrams per liter rather than milliliters per liter.
tom-fiegen Tue 6 Jan 4:30 PM