Assessing the impact of industrial agriculture on water quantity and quality in the Park Rapids region

Intensive agricultural production, also referred to as industrial agriculture, is commonly associated with negative impacts on surface water quality and groundwater quality. Such conditions are presumably developing in the region within the Crow Wing watershed, particularly within the counties of Cass, Hubbard, Becker, and Wadena. There, large areas of land formerly in perennial woods, shrubs, forbs, and grasses, are being converted to intensive row crop agricultural land to produce potatoes.

Because the soils in the region are coarse-grained, and the water table is relatively close to the land surface, the surficial aquifer in the region is highly susceptible to nitrate, phosphorus, and pesticide contamination. Besides the potential for increased contamination of the surficial aquifers, there is an increase in water use for irrigation for the row crop production and this increase in use of groundwater resources has the potential to disconnect streams, wetlands, and lakes from the surficial aquifer, thus impacting water levels in wetlands and lakes, and reducing baseflows in streams. The contamination of the groundwater also has the potential to increase nitrate, phosphorus and pesticide concentrations in these surface waters. 

There is a need to quantify the impact of intensified agricultural production on the quantity and quality of surface waters and groundwater. The present study has the objective to make such a quantification. The study has the following sub-objectives:

  1. Evaluate streamflow data for the region to identify trends in streamflows and water levels in lakes, taking into account trends in precipitation and regional evaporation.
  2. Identify the sources of nitrate that are leading to the contamination of well water in the region.
  3. Develop a calibrated groundwater flow model for the region using the GMS-MODFLOW software.
  4. Develop a calibrated surface water hydrology model for the region using the SWAT model.
  5. Apply the calibrated models to quantify the potential for groundwater contamination by nitrate leaching beneath the row-crop agricultural operations, and the potential to impact streamflows (quantity and quality, and wetland and lake levels and water quality in the region.
  6. Assess alternative strategies for reducing any detrimental impacts of industrial agriculture operations on water quantity and quality.

The study will provide the opportunity to train graduate students and undergraduate students in the application of hydrologic models, analysis of hydrologic and water quality data, assessment of best management practices to mitigate negative impacts of intensive agricultural activities, and to gain an appreciation for the rights of indigenous peoples to have access to clean water and to practice the rights afforded by long-standing treaties.