Minneapolis Park & Recreation Board WATER RESOURCES REPORT 2017 Environmental Management 2017 WATER RESOURCES REPORT Prepared by: Minneapolis Park & Recreation Board Environmental Management 3800 Bryant Avenue South Minneapolis, MN 55409-1029 612.230.6400 www.minneapolisparks.org December 2018 Funding provided by: Minneapolis Park & Recreation Board City of Minneapolis Public Works Copyright © 2018 by the Minneapolis Park & Recreation Board Material may be quoted with attribution. TABLE OF CONTENTS Page Abbreviations ............................................................................................................................. i Executive Summary ............................................................................................................... iv 1. Monitoring Program Overview .............................................................................................. 1-1 2. Birch Pond .............................................................................................................................. 2-1 3. Brownie Lake ......................................................................................................................... 3-1 4. Calhoun / Bde Maka Ska ........................................................................................................ 4-1 5. Cedar Lake ............................................................................................................................. 5-1 6. Diamond Lake ........................................................................................................................ 6-1 7. Grass Lake .............................................................................................................................. 7-1 8. Lake Harriet ............................................................................................................................ 8-1 9. Lake Hiawatha ........................................................................................................................ 9-1 10. Lake of the Isles ................................................................................................................... 10-1 11. Loring Pond .......................................................................................................................... 11-1 12. Lake Nokomis ...................................................................................................................... 12-1 13. Powderhorn Lake ................................................................................................................. 13-1 14. Ryan Lake ............................................................................................................................ 14-1 15. Spring Lake .......................................................................................................................... 15-1 16. Wirth Lake ............................................................................................................................ 16-1 17. Comparisons Among Lakes ................................................................................................. 17-1 18. Public Beach Monitoring ...................................................................................................... 18-1 19. Webber NSP ......................................................................................................................... 19-1 20. Aquatic Plant Management .................................................................................................. 20-1 21. Wetland Health Evaluation Program (WHEP) ..................................................................... 21-1 22. National Pollutant Discharge Elimination System (NPDES) Monitoring ............................ 22-1 23. Lowry Sand Filter ................................................................................................................. 23-1 24. Winter Infiltration Basin ...................................................................................................... 24-1 25. 24th & Elm Infiltration Chamber .......................................................................................... 25-1 26. Golf Course Wetland Monitoring ......................................................................................... 26-1 27. Climatological Summary ...................................................................................................... 27-1 28. Water Quality Education ...................................................................................................... 28-1 29. Quality Assurance Assessment Report ................................................................................. 29-1 30. Additional Sources of Water Quality Information ............................................................... 30-1 31. References ............................................................................................................................ 31-1 Appendix A – Box and Whisker Plot Record ....................................................................... A-1 Appendix B – Lake Monitoring Data 2017 .......................................................................... B-1 2017 Water Resources Report – Minneapolis Park & Recreation Board LIST OF ABBREVIATIONS % DO Percent Dissolved Oxygen µg Microgram µm Micrometer µmhos Micromhos µS Micro Siemens ACSP Audubon Cooperative Sanctuary Program Al Aluminum Alk Alkalinity alum Aluminum sulfate As Arsenic BCWMC Bassett's Creek Watershed Management Commission BMP Best Management Practices C Celsius CAMP Citizen Assisted Monitoring Program cBOD 5 day Carbonaceous Biochemical Oxygen Demand Cd Cadmium CDS Continuous Deflective Separation cf Cubic foot cfs Cubic foot per second cfu Colony forming unit chl-a Chlorophyll-a Cl Chloride cm Centimeter COD Chemical Oxygen Demand Cond Conductivity Cu Copper CV Coefficient of Variance CWP Center for Watershed Protection DO Dissolved Oxygen E. coli Escherichia coli ERA Environmental Resource Associates EWM Eurasian watermilfoil F Fahrenheit F. coli Fecal Coliform Fe Iron FIN Fishing in the Neighborhood Program ft Foot GIS Geographical Information System GPS Global Positioning System Hard Hardness, Total as CaCO3 HPLC High Pressure Liquid Chromatography IBI Index of Biological Integrity 2017 Water Resources Report – Minneapolis Park & Recreation Board Page i ID Insufficient Data in/hr Inches per hour IRI Instrumental Research, Inc. IWMI Interagency Water Monitoring Initiative kg Kilogram L Liter LAURI Lake Aesthetic and User Recreation Index m Meter MAX Maximum MCES Metropolitan Council Environmental Services MCWD Minnehaha Creek Watershed District MDL Minimum Detection Limit MDNR Minnesota Department of Natural Resources mg Milligram MIN Minimum mL Milliliter Mn Manganese MnDOT Minnesota Department of Transportation MPCA Minnesota Pollution Control Agency Mpls Minneapolis MPN Most probable number MPRB Minneapolis Park and Recreation Board MPW Minneapolis Public Works msl Mean sea level MRL Minimum Reporting Limit N/A Not Applicable n/c Not Collected NA No Data Available NB No Swimming Beach NCHF North Central Hardwood Forests ND Not Detected NDC National Data Center NH3 Ammonia, Un-ionized as N Ni Nickel NO3/NO2 Nitrate+Nitrite NOAA National Oceanic and Atmospheric Administration NOx Nitrite+Nitrate, Total as N NPDES National Pollutant Discharge Elimination Systems NS Not Sampled NTU Nephelometric Turbidity Unit NURP Nationwide Urban Runoff Program NWS National Weather Service OHW Ordinary High Water Level OTP Ortho Phosphorus P Phosphorus 2017 Water Resources Report – Minneapolis Park & Recreation Board Page ii Pb Lead PE Performance Evaluation PFC Perflorinated Chemical PFOA Perflurorooctanoic Acid PFOS Perfluorooctane Sulfonate QA Quality Assurance QAPP Quality Assurance Project Plan QC Quality Control RL Reporting Limit RPD Relative Percent Difference s Second Si Reactive Silica Sp. Cond. Specific Conductivity SRP Soluble Reactive Phosphorus STDEV Standard Deviation TCMA Twin Cities Metropolitan Area TDP Total Dissolved Phosphorus TDS Total Dissolved Solids TKN Total Kjeldahl Nitrogen TMDL Total Maximum Daily Load TN Total Nitrogen TOC Total Organic Carbon TP Total Phosphorus TRPD Three Rivers Park District TSI Trophic State Index TSS Total Suspended Solids US EPA US Environmental Protection Agency USGS US Geological Survey VSS Volatile Suspended Solids WHEP Wetland Health Evaluation Program WOMP Watershed Outlet Monitoring Program WPA Works Progress Administration Zn Zinc 2017 Water Resources Report – Minneapolis Park & Recreation Board Page iii EXECUTIVE SUMMARY As part of its stewardship of the lakes and other water bodies within the City of Minneapolis, the Minneapolis Park and Recreation Board (MPRB) monitors lakes, streams, and stormwater flows for contaminants and other water quality indicators. This report presents the results for the 2017 monitoring season. The report is primarily based on data collected by the MPRB Environmental Management Section. In 2017, MPRB water resources scientists monitored 11 of the city’s most heavily used lakes: Bde Maka Ska, Cedar, Diamond, Harriet, Hiawatha, Isles, Loring, Nokomis, Powderhorn, Spring, and Wirth Lakes. Historical data from 1991-2017 are used to calculate trophic state index (TSI) trends and estimate the trophic status for each lake. Diamond and Grass Lakes were not included in this analysis since TSI scores are only appropriate for deeper lake systems and there are no water clarity measurements