Natalia Welzenbach-Marcu | June 18th, 2019

Nitrates are not a new subject for Iowans. We’ve already published a nitrate breakdown that explains the nitrate pollution contributions Iowa makes to the many larger bodies of water our rivers drain into and how nitrate pollution can affect our bodies.

With some new research emerging, it’s become clear that Iowa’s nitrate problem is intricately linked with its status as a heavily agricultural state–our amounts of livestock have a heavy effect on the quality of our water, and the problem may be larger than we realize.

Back in March, Chris Jones, a research engineer from IIHR, broke down what he calls Iowa’s “real population”–a collective census of our state’s population, one that includes more than just its people. By calculating the amounts of nitrogen, phosphorus, and total solid matter excreted by different types of livestock and comparing those values to human waste, he was able to roughly calculate how many people each livestock group accounted for–and the numbers are staggering.

According to this line of logic, pigs in Iowa roughly equal a mind-blowing 83.7 million people. Dairy and beef cattle account for 33.6 million people. Chickens and turkey nearly equal 16 million themselves. Altogether, our livestock theoretically gives Iowa–a relatively small state with less than 4 million humans–an extended population of about 134 million. Recently, Chris Jones applied his research to Iowa’s actual area to determine the concentration of those numbers, and, in the process, updated that overall population to 168 million after some new data from the USDA.

Iowa produces a lot of waste. Livestock-heavy watersheds tend to have higher concentrations of nitrate runoff. We are not a large state, but when we account for our animals, we are one of the most densely populated for our total land area.

Overall, dissecting the effect that agriculture and livestock have on the environment is tricky, because our state relies heavily on our agricultural economy for many, many things. Advancements in green and natural nitrate filters and better methods of waste management seem to be some of the solutions we can work towards to solve our looming nitrate problem.