Most streams in the Mississippi River-La Crescent watershed support good water quality, according to a new report by the MPCA.
Almost half of the watershed is wooded, helping protect the water quality of trout streams by keeping soil in place, shading streams and keeping them cool, and otherwise providing good habitat. Maintaining this woodland and implementing more stream buffers to provide shade and erosion protection, is key to protecting water in this area.
The streams in this watershed continue to recover from a devastating flood in 2007 after 8 to 14 inches of rain fell in this area in 24 hours. The floods washed out roads, buildings, and railroad tracks. They also changed or moved streams. Subsequent floods in 2009 and 2010 continued the damage. Addressing climate change and the potential for flooding will be key for landowners and government working to protect water resources.
This area is known for its karst geography. Karst is like the Swiss cheese of rock. The landscape is dotted with sinkholes, springs, caverns, and underground waterways.
As water flows through karst, it mixes above and below ground. This mixing means pollutants on land can easily reach groundwater used for drinking. Protecting the streams are important for ensuring safe drinking water and for the economic impact of tourists visiting this area to fish, hike, and camp.
The Mississippi River-La Crescent watershed drains 95 square miles in Houston and southeast Winona counties, an area defined by wooded bluffs and spring-fed cold-water streams that flow directly to the Mississippi River. Pine Creek is the largest cold-water tributary in the watershed, running through a steep valley with erodible soils. These natural conditions, coupled with poor pasturing practices, cattle accessing the stream, and higher flows eroding the streambanks, result in high levels of sediment that make the water cloudy. The upper part of Pine Creek — where it starts — is in good condition, but downstream habitat and temperature conditions worsen and that harms cold-water fish and other water creatures.
Landowners have long been engaged in good land stewardship practices, planting row crops at or near the bluff tops, using contour stripping, terracing fields, and other practices to prevent erosion and keep fields stable. Maintaining and expanding these practices is important for protecting water quality, and controlling flow and erosion related to flooding.
Read the full report: Mississippi River-La Crescent Stressor Identification Report