IIHR oversees water quality sensors that update the data on the quality of the Iowa River in real time.
By Katelyn Weisbrod
Underneath the cloudy water of the Iowa River lie state-of-the-art sensors that provide real-time updates on water quality.
The University of Iowa’s IIHR-Hydroscience and Engineering oversees 26 of these sensors located in water bodies across Iowa. The project began in 2012 with just six sensors. This coming spring, IIHR plans to add 15 more, giving it 41 sensors throughout the state.
The project contributes to the Iowa Nutrient Reduction Strategy, an ongoing effort to reduce the amount of fertilizer draining into the Mississippi River and, ultimately, the Gulf of Mexico. Nitrate is a common farm fertilizer, and storm runoff can wash nitrates into river water, diminishing the quality.
“Our primary intention — especially next year — will be to quantify the load of nitrate leaving the state of Iowa,” IIHR research scientist Chris Jones said. “We want to trend that over time to see if the practices we’re implementing for the Nutrient Reduction Strategy are indeed working and reducing loss from farm fields.”
Jones said approximately half of the 26 currently deployed sensors measure more than nitrate. They also track dissolved oxygen, conductivity, acidity, temperature, and other aspects indicative of water quality.
Each of the sensors cost around $16,000, Jones said, and the project is largely funded by the Iowa Nutrient Center.
“That’s just the cost of purchasing equipment,” Jones said. “Along with deploying the device, there’s things like lumber, PVC, solar panels, batteries to operate the device, and necessary equipment to transmit the data back to Iowa City.”
Once the data are sent back to Iowa City, researchers analyze the results.
“It’s pretty remarkable — the quality and the amount of data that comes in from the sensors across the state,” IIHR research scientist Keith Schilling said. “It’s no small task to look at this and analyze what the data are telling us.”
The data are not just for research; they are available online to anybody who wants to delve through into them.
“People don’t know. We look at the river, and it always looks muddy and brown, but we don’t know whether it’s better or worse than usual,” IIHR communications manager Jackie Stolze said.
Iowa was the first state to have these water-quality sensors, she said, but now they are used in more than 100 locations across the United States.
“I know in Florida, there are quite a few nitrate-measurement devices, and in California, Illinois Indiana, and maybe Kansas,” she said. “But Iowa was the first, and we have by far the largest assembly of these real-time devices.”