Assessment Report of Selected Lakes within the Sauk River Watershed Minnesota Pollution Control Agency Water Monitoring Section Lakes and Streams Monitoring Unit July 2010 Minnesota Pollution Control Agency 520 Lafayette Road North Saint Paul, MN 55155-4194 http://www.pca.state.mn.us651-296-6300 or 800-657-3864 toll free TTY 651-282-5332 or 800-657-3864 toll free Available in alternative formats Author Matt Lindon Geographical Information System Mapping Kris Parson Editing Steve Heiskary Dana Vanderbosch Minnesota Pollution Control Agency Water Monitoring Section Lakes and Streams Monitoring Unit wq-ws3-07010202 The MPCA is reducing printing and mailing costs by using the Internet to distribute reports and information to wider audience. For additional information, see the Web site: www.pca.state.mn.us/water/lakereport.html 2010 Assessment of Selected Lakes Minnesota Pollution Control Agency Within the Sauk River Watershed May 2010 i This report was printed on recycled paper manufactured without the use of elemental chlorine (cover: 100% post-consumer; body: 100% post-consumer) 2010 Assessment of Selected Lakes Minnesota Pollution Control Agency Within the Sauk River Watershed May 2010 ii Table of Contents Table of Contents ......................................................................................................................................iii List if Figures ............................................................................................................................................ vi List of Tables ............................................................................................................................................ ix Executive Summary ................................................................................................................................... 1 Introduction to the Watershed Approach ................................................................................................... 2 Sauk River Watershed ................................................................................................................................ 3 Landuse ........................................................................................................................................... 5 Climate............................................................................................................................................ 7 Lake Monitoring in the Sauk River Watershed .............................................................................. 8 Background to Lake Assessments ............................................................................................................. 9 Lake Mixing ................................................................................................................................... 9 Trophic Status Indicators .............................................................................................................. 10 Modeling ....................................................................................................................................... 11 303(d) Assessments ...................................................................................................................... 11 Methods ........................................................................................................................................ 12 11 Digit HUC discussions ........................................................................................................................ 13 Upper Sauk River HUC 11 ...................................................................................................................... 13 Smith Lake 21-0016 ................................................................................................................................. 16 Water Quality Summary ............................................................................................................... 17 Water Quality Trends ................................................................................................................... 18 Modeling and Assessment Status ................................................................................................. 18 Osakis 77-0215 ........................................................................................................................................ 19 Water Quality Summary ............................................................................................................... 20 Water Quality Trends ................................................................................................................... 20 Modeling and Assessment Status ................................................................................................. 21 Maple Lake 77-0181 ................................................................................................................................ 22 Water Quality Summary ............................................................................................................... 23 Water Quality Trends ................................................................................................................... 24 Modeling and Assessment Status ................................................................................................. 24 Fairy Lake 77-0154 .................................................................................................................................. 25 Water Quality Summary ............................................................................................................... 26 Water Quality Trends ................................................................................................................... 27 Modeling and Assessment Status ................................................................................................. 27 Little Sauk 77-0164.................................................................................................................................. 28 2010 Assessment of Selected Lakes Minnesota Pollution Control Agency Within the Sauk River Watershed May 2010 iii Water Quality Summary ............................................................................................................... 29 Water Quality Trends ................................................................................................................... 30 Modeling and Assessment Status ................................................................................................. 30 Sauk Lake 77-0150 .................................................................................................................................. 31 North Sauk Lake ........................................................................................................................... 31 77-0150-01.................................................................................................................................... 31 Water Quality Summary ............................................................................................................... 32 Water Quality Trends ................................................................................................................... 32 Modeling and Assessment Status ................................................................................................. 33 Lower Sauk Lake .......................................................................................................................... 34 77-0150-02.................................................................................................................................... 34 Water Quality Summary ............................................................................................................... 34 Water Quality Trends ................................................................................................................... 35 Modeling and Assessment Status ................................................................................................. 35 Ashley Creek HUC 11 ............................................................................................................................. 36 Westport 61-0029..................................................................................................................................... 38 Water Quality Summary ............................................................................................................... 39 Water Quality Trends ................................................................................................................... 39 Modeling and Assessment Status ................................................................................................. 39 Hoboken Creek HUC 11 .................................................................................................................. 40 Middle Sauk River ................................................................................................................................... 41 Kings 73-0233 .......................................................................................................................................... 43 Water Quality Summary ............................................................................................................... 44 Water Quality Trends 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