Groundwater quality is an ever-present concern in Nebraska as the majority of the state’s drinking water is sourced from groundwater. Since the mid-1900’s, areas of Nebraska have been subjected to surface activities that have led to elevated nitrate concentrations in groundwater. Shallow aquifers with soils and geology that allow for rapid recharge are often the first to have groundwater with higher nitrate concentrations. However, deeper groundwater systems are not immune to contaminants. Often, the longer a groundwater system is subjected to nitrate and pesticides, the greater the risk of higher concentrations.
The Conservation and Survey Division is working to evaluate the vulnerability of groundwater and surface water quality and identify areas in Nebraska where groundwater may favorably respond to changes in management practices. Groundwater transit times and related groundwater age assist in determining the rate at which groundwater and nitrate are transported into and through aquifers. Understanding how quickly a contaminant will be flushed out of an aquifer via pumping or through natural groundwater discharge into hydrologically connected or nearby streams is a key component to protecting of one of Nebraska’s most valuable natural resources.