Little Rock Creek, a cold-water trout stream in central Minnesota, is impaired due to the lack of trout and other cold water fish. The trout are absent because of high water temperatures, low dissolved oxygen and high nitrate levels, stressors caused from a lack of base flow and overuse of groundwater. This project continues a 2011 initiative to assist irrigators in the Little Rock Creek groundwater recharge area with managing the timing and amount of irrigation applied to their crops.
This project combines the use of automated soil moisture probes for irrigation scheduling with diverse cover crop planting to reduce or eliminate leaching of nitrogen and other nutrients on cropland with an early season harvested crop in the rotation. The more efficient use of irrigation waters provides a secondary benefit: less withdrawal from the aquifers that provide recharge for the Mt. Simon-Hinckley aquifer.