Common Carp Assessment in Six Mile Creek Summary Report: June 2014 - February 2016

The Six Mile Creek Subwatershed is predominately agricultural and parkland, but is presently facing increasing urban development pressure. Located in the southwest corner of the Minnehaha Creek Watershed District (MCWD), it spans roughly 27 square miles and encompasses a chain of 17 lakes (Piersons, Marsh, Wassermann, Carl Krey, Kelzer's, Church, East Auburn, West Auburn, Steiger, Sunny, Zumbra, Stone, North Lundsten, South Lundsten, Turbid, Parley, & Mud) and over a dozen unnamed ponds and wetlands (Figure 1). This system flows north from Piersons Lake and eventually drains into Halsted's Bay of Lake Minnetonka. Water quality in the Six Mile Creek Subwatershed varies by lake, but many lakes are highly degraded and devoid of healthy native submersed plant communities. Additionally, several lakes currently fail to meet state nutrient standards and are classified as impaired for excess nutrients (phosphorus). Because internal loading was identified as a significant driver of in-lake phosphorus concentrations in this system, common carp assessment and management was recommended (Wenck Associates 2013). In 2014, MCWD partnered with the University of Minnesota to initiate a three-year study to obtain a better understanding of the common carp population(s) in the Six Mile Creek Subwatershed to inform sustainable control strategies. This report summarizes the scientific findings of the first two years of this study and provides subsequent tentative management recommendations.