Vadose Zone Study Update, Fall 2023

Vadose Zone Study Update, Fall 2023

The Upper Big Blue NRD has partnered with the University of Nebraska-Lincoln to take part in a research study focusing on investigating the vadose zone. The vadose zone is the area beneath the root zone and above the groundwater table. It is also referred to as the unsaturated zone. The focus of the study will be to look at groundwater nitrate and agrichemical contaminant occurrence in the vadose zone. To do this, we will be looking at both historic and spatial changes in groundwater nitrate throughout the district and in the 12 water quality management zones to compare the changes in nitrate levels. Nitrate levels will be determined by drilling test holes for chemical analysis, along with characterizing the soil type and physical characteristics. 

For the past few decades, we have seen a steady increase in nitrogen concentration in some parts of the district. To see the zone you are in, please refer to the map below. While we have seen decreases in some areas of the district, we have had an overall increase of 54 percent. You can see maps displaying median nitrate levels here.

We will be continuing in the fall of 2023, and we are looking for volunteers who will be willing to take part in the study. Volunteers, if selected, will be asked to fill out a survey to look at current and historical management practices on the fields to be used in the study. For the fall of 2023, we will be sampling in zones 6,7, and 8. In the spring of 2024, we will be sampling in zones 1, 2, and 3. Finally, in the fall of 2024 we will finish up in zone 9, 10, 11, and 12. If you have any questions, or are interested in participating in the study, feel free to contact Dawson Tietmeyer at


GWMA Zones

vadose zone study