Nitrate

What is Nitrate and where does it come from?

Katie Pekarek, Water Quality Extension Educator, University of Nebraska & Crystal Powers, Research and Extension Communications Specialist, Nebraska Water Center

Nitrogen is a valuable fertilizer source that keeps Nebraska growing abundant landscapes and crops. Nitrogen that does not get used by the crop ends up in our streams, lakes and groundwater. Nitrate is the most common form of nitrogen found in water.

Impacts (Health, Economic, and Recreation)

Nitrate in Nebraska waters has economic, recreation, and health impacts for all of our citizens.

  • Farmers recognize the economic and opportunity loss of nitrogen that is not utilized for growing crops.
  • Millions of tax dollars are managed by Natural Resources Districts, Cities, and conservation agencies to prevent and treat nitrate contamination of water annually.
  • Nearly 1 in 5 Public Water Supplies and private wells in Nebraska consistently tests high for nitrate-nitrogen.  This number is growing. (NDEE Groundwater Report, Risk and Cost Assessment of Nitrate Contamination in domestic wells).
  • Nitrate is a significant contributor to the presence of Harmful Algal Blooms (HABs). Public beaches in Nebraska are monitored for HABs and closed if the level gets to high.  
  • Long term exposure of high nitrate levels can harm fish and their habitats as the result of excessive aquatic plant growth, modified pH, and lowered dissolved oxygen levels.
  • Research has long shown that nitrate exposure is a hazard for infants.  Emerging research has demonstrated strong links with high nitrate concentrations in drinking water and lifetime risk of negative birth outcomes, thyroid disease, and certain cancers (Reference). The drinking water standard for nitrate in water is 10 mg/L.

Another Dry Year: What to Know About Leftover Nitrogen in Soil Following Dry Conditions

With the two consecutive dry seasons in 2021 and 2022, there is likely a considerable amount of unused nitrogen left in the soil, which could be used for the 2023 crop. With the higher fertilizer prices, such fertility adjustments for next crop can be profitable as well as environment friendly. So, it is recommended to test your soil and account for all sources of nutrients for the next crop.

Rural Nebraskans Voice Water Quality Concerns

Photo Credit: Craig Chandler | University Communication and Marketing A majority of respondents to the 2022 Nebraska Rural Poll indicated they were at least somewhat concerned about contaminants in their water supply that could impact their own or their family’s health. About 45% reported they had had their water tested for nitrates, E. coli, lead, pesticides or other contaminants.

Rust-stained irrigation pipes hint at lack of nitrate in groundwater

According to study from Department of Natural Resources researchers, irrigation pivots stained with rust may indicate the absence of nitrate in the groundwater supplying the pivots. This information can potentially be used to help screen for areas for the potential absence of nitrate and, in an ideal world, could indicate areas at higher- or lower-risk for nitrate contamination before it becomes a problem.

Reverse Osmosis In-Service: Treating high nitrate concentrations in private wells

In 2023, the Nebraska Legislature passed LB1014.  This bill took 4 million dollars from the American Rescue Plan Act and allocated it to treating nitrate issues in Nebraska.  1.2 million dollars of that has been dedicated to a Reverse Osmosis Rebate Program that is directed at private well owners. The general idea of the program is that any individual private drinking water well owner can test their water AND if the nitrate concentration comes back above 10 ppm, they might be eligible for UP TO $4,000 support to get a reverse osmosis system to treat their nitrate.

Understanding Soil Residual Nitrogen and its Dollar Value for Next Crop

For producers planning corn-on-corn this growing season, there may be a substantial opportunity to reduce nitrogen fertilizer applications, as drought and reduced yields likely left higher-than-normal residual N in many fields.

Alfalfa in Rotation with Annual Crops Reduces Nitrate Leaching Potential and Increases Soil Organic Carbon Sequestration

This UNL research study provides insights on the rotation of annual crops with alfalfa as a highly effective means of reducing nitrate-nitrogen contamination in groundwater.

Don’t Lose Out on Free Nitrogen from Irrigation Water

Extension recommendations for calculating the amount of nitrate-nitrogen in irrigation water and optimal timing of applications to reduce the cost of nitrogen inputs in irrigated corn.

Know Your Well program empowers students to understand local water quality

Access to quality water is critical. Testing can indicate whether water is safe for people to consume. Know Your Well is a program used to test well water across Nebraska at no cost to the community, while teaching local high school students valuable skills. In the past seven years, Know Your Well has been implemented in more than 28 school districts throughout the state. The program has received funding to grow to 50 or more schools over the next few years and expand its curriculm.

100 years of Nebraska nitrogen

Nitrogen is an essential plant nutrient but increasingly found in our water. Here is a brief history:

Thompson Discusses New Nitrogen Management Tool on RFD-TV

Nebraska Extension Educator Laura Thompson shares insights on how UNL's new nitrogen tool will help farmers determine fertilizer needs for their operation and find more success in their overall farm management goals.

What is Nitrate and where does it come from?

Katie Pekarek, Water Quality Extension Educator, University of Nebraska & Crystal Powers, Research and Extension Communications Specialist, Nebraska Water Center

Nitrogen is a valuable fertilizer source that keeps Nebraska growing abundant landscapes and crops. Nitrogen that does not get used by the crop ends up in our streams, lakes and groundwater. Nitrate is the most common form of nitrogen found in water.

Impacts (Health, Economic, and Recreation)

Nitrate in Nebraska waters has economic, recreation, and health impacts for all of our citizens.

  • Farmers recognize the economic and opportunity loss of nitrogen that is not utilized for growing crops.
  • Millions of tax dollars are managed by Natural Resources Districts, Cities, and conservation agencies to prevent and treat nitrate contamination of water annually.
  • Nearly 1 in 5 Public Water Supplies and private wells in Nebraska consistently tests high for nitrate-nitrogen.  This number is growing. (NDEE Groundwater Report, Risk and Cost Assessment of Nitrate Contamination in domestic wells).
  • Nitrate is a significant contributor to the presence of Harmful Algal Blooms (HABs). Public beaches in Nebraska are monitored for HABs and closed if the level gets to high.  
  • Long term exposure of high nitrate levels can harm fish and their habitats as the result of excessive aquatic plant growth, modified pH, and lowered dissolved oxygen levels.
  • Research has long shown that nitrate exposure is a hazard for infants.  Emerging research has demonstrated strong links with high nitrate concentrations in drinking water and lifetime risk of negative birth outcomes, thyroid disease, and certain cancers (Reference). The drinking water standard for nitrate in water is 10 mg/L.