How clean is our water?

Sarah Hays

We swim in it, drink it, clean with it and even shower in it, but how much do we really know about it?

Water, the fluid that makes up over half of our bodies and 71 percent of the world, is a resource most people here in the Midwest don’t think twice about having.

But alarmingly, the tap water we drink straight from the sink, or even a hose, may not be as safe as one might believe.

Here in Iowa, the quality of our water is changing year by year. There are three main factors that impact the quality of the water we drink. These elements: Sediment, nutrients and bacteria, all play a part in the safety and health of our water.

For the average student at Iowa State, these terms may seem familiar, but not exactly understandable. So here’s a breakdown of what these ingredients to the quality of Iowa’s water are, and how students across campus can fix it.


“Sediment is the biggest problem we have,” said Dan Jaynes, affiliate professor and USDA employee. “When you can’t see through the river or see the bottom because it’s brown, that’s sediment being held up in the water or the river.”

In natural, flowing water, the sediment is the fine soil particles, like dirt, clay or organic matter that fuse into the water. Both animals and people can interact around this water.


There are two nutrients in the water around us that can potentially be very toxic to not only the people, but also the environment.

Potentially toxic to people and animals, nitrate, a form of nitrogen, is a growing problem in agriculture.

“Nitrate’s a problem because if you get above 10 mg/liter of nitrate, you can’t drink that water. It can be poisonous to newborns, and most water in Iowa that comes off our fields is above that 10 mg/liter,” Jaynes said. Although, people above six months old are not typically bothered by drinking the nutrient.

Farmers use nitrate for crops, which consume nitrate to grow. But a lot of times crops don’t use all the nitrate they receive.

When the nitrate does not get absorbed, it runs off of the land into streams, and eventually runs through rivers into the Gulf of Mexico. Today, there is a certain part of the gulf called the ‘Dead Zone.’

The ‘Dead Zone’ is an accumulation of nitrate, resulting in the nutrient absorbing oxygen. This lack of oxygen kills off fish, shrimp, clams and other ocean creatures, forming an uninhabitable area. Attempts to prevent the ‘Dead Zone’ from growing are happening here in Iowa and across the Midwest.

“It kills everything because there’s not oxygen left,” Jaynes said.

“The states that are in the Mississippi River Basin are trying to set goals to try and reduce their nitrate export down to the Gulf of Mexico,” said Michelle Soupir, researcher and associate professor in agricultural and biosystems engineering.

The second nutrient in local water prior to filtration is phosphorous. Also used as a fertilizer, the nutrient is a more local issue than nitrate, Soupir said.

“It is one of our biggest problems in Iowa, and across the whole country,” Jaynes said. “You get too much phosphorous into fresh water, and it really dries bacterial or algae growth.” 

Phosphorous is a problem that is visually seen. Lakes and rivers can appear to be completely green due to an overload of phosphorous in the water. For example, Big Creek Lake, a popular spot for students to visit, contains a lot of phosphorous by the end of the summer.

“Big Creek, which is around here, gets pea green by August, and that’s because of phosphorous,” Jaynes said.


Bacteria, although not as harmful to the environment, is prominent in the water and soil of Iowa. Some of this bacteria can make people ill, such as E-coli, which is a bacterial virus that is commonly mistaken for food poisoning.

“That’s probably why you don’t want to drink that water. It’s not the sediment, not the nutrients, it’s the fact that there’s a lot of bacteria in that water,” Jaynes said.

When it comes to water quality, bacteria are the least harmful contributor to the water. Although, problems with bacteria still arise if there is a lack of filtration process.

These three attributes of water quality are problems that can be solved. While it could take centuries to completely annihilate these issues, there are two strategies currently being practiced to better the quality of Iowan water.

Tile Drainage with Bioreactors

Across Iowa, tile drainage is visible around the ditches of most country roads. There are pipes that stick out at the bottom of the ditches. These pipes release excess water from fields.

The nitrate that runs through the pipes is filtered through bioreactors. Using wood chips, a bioreactor uses a process called denitrification to covert nitrate to nitrogen gas.

“Denitrification is taking the nitrate that’s in the drainage water and the microbes in this anaerobic (lack of oxygen) condition so it’s completely saturated and they need an oxygen source, so they strip the oxygen and convert the nitrate to nitrogen gas,” Soupir said.


Another solution to enhance healthy water quality is the usage of wetlands.

“Wetlands are like the kidneys of a landscape. They take all the junk, all the nutrients, bacteria and sediment, and they use it for good,” said Adam Janke, extension wildlife specialist and assistant professor in natural resource ecology and management.

Wetlands here in Iowa are rare. But centuries ago, they were flourishing. Farmers drained wetlands in order to farm on the land, forming tile drainage.

“300 years ago, we had 96 percent more of wetlands than we do now. We have less now because of drainage,” Soupir said.

Today, people do not use current wetlands for farming like they did centuries ago. In fact, wetland restoration is a growing practice.

While tile drainage is a solution to nitrate release, wetlands filter and absorb nitrate before it goes into streams. Adding wetlands to farmland can be a way to reduce nitrate in the water.

But what can the average person do?

Everybody plays a role in water quality. Local Iowans can take small and simple steps to improving their own quality of water.

“You can do simple stuff, like picking up after your dog, because that is a bacteria source,” Janke said.

Awareness is also a step to understanding the problem. Students coming to Iowa State are gaining interest in this topic, which will help increase the awareness in the community.

“There’s more talk about water quality now than there was when I first came here,” Soupir said.

Whether it is simply learning about the issue or cleaning up after your pets, the typical person in Iowa can help take a step toward cleaner water.

“Everybody has a role to play in water quality. Even if you live in an apartment in Ames, you can do something for water quality,” Janke said.