Nitrate concentrations of the Iowa River at Wapello, 2017.

These summaries are an aggregation of IIHR and USGS water quality sensor data, Iowa DNR ambient monitoring data, and USGS discharge data.

An overview of the 2017 NO3-N totals.

As we go about our regular lives, a billion of anything seems like a whole lot. For example, if you need to count a billion things, it’s going to take a while. An 80-year lifespan would include only 42 million seconds, not even close to one billion (0.042).

Nitrate concentrations of the Turkey River in 2017.

Year to year variations in nitrate loads (total mass delivered to streams) are really driven by precipitation and discharge, and the effect is not linear.

The graph below shows Raccoon River nitrate loads (metric tons) from January through June (blue bars) versus the annual load (red bars).

Just posting some graphs of recent data here of the last two months and historical perspective.

More than 90 percent of the nitrogen transported by Iowa streams is in the form of nitrate (NO3-N).

When Iowans straightened rivers and creeks in the 20th century, they likely didn’t understand the chain reaction they had set in motion. They simply wanted to make their land easier to farm. But according to IIHR Research Engineer Chris Jones, the straightened dredge ditches of today are disconnected from the floodplain and have lost much of their ability to process nutrients. The water moves faster, eroding downward and increasing the flood risk downstream.