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Minnesota Lake Water Quality Assessment Report: Developing Nutrient Criteria

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Minnesota Lake Water Quality Assessment Report: Developing Nutrient Criteria MINNESOTA LAKE WATER QUALITY ASSESSMENT REPORT: DEVELOPING NUTRIENT CRITERIA Third Edition September 2005 wq-lar3-01 MINNESOTA LAKE WATER QUALITY ASSESSMENT REPORT: DEVELOPING NUTRIENT CRITERIA Third Edition Written and prepared by: Steven A. Heiskary Water Assessment & Environmental information Section Environmental Analysis & Outcomes Division and C. Bruce Wilson Watershed Section Regional Division MINNESOTA POLLUTION CONTROL AGENCY September 2005 Acknowledgments This report is based in large part on the previous MLWQA reports from 1988 and 1990. Contributors and reviewers to the 1988 report are noted at the bottom of this page. The following persons contributed to the current edition. Report sections: Mark Ebbers – MDNR, Division of Fisheries Trout and Salmon consultant: Stream Trout Lakes report section Reviewers: Dr. Candice Bauer – USEPA Region V, Nutrient Criteria Development coordinator Tim Cross – MDNR Fisheries Research Biologist (report section on fisheries) Doug Hall – MPCA, Environmental Analysis and Outcomes Division Frank Kohlasch – MPCA, Environmental Analysis and Outcomes Division Dr. David Maschwitz – MPCA, Environmental Analysis and Outcomes Division Word Processing – Jan Eckart ----------------------------------------------- Contributors to the 1988 edition: MPCA – Pat Bailey, Mark Tomasek, & Jerry Winslow Manuscript review of 1988 edition: MPCA – Carolyn Dindorf, Marvin Hora, Gaylen Reetz, Curtis Sparks & Dr. Ed Swain MDNR – Jack Skrypek, Ron Payer, Dave Pederson & Steve Prestin University of Minnesota – Dr. Robert Megard, Dr. Joseph Shapiro & Dr. Patrick Brezonik St. Anthony Falls Hydraulic Laboratory – Dr. Heinz Stefan & Dr. Mike Riley Kent State University – Dr. Dennis Cooke USEPA-Environmental Research Laboratories (Corvallis) – Sharon Clark, James Omernik, & Thom Whittier; (Duluth) Dr. Gary Glass Metropolitan Council – Dick Osgood TABLE OF CONTENTS Page LIST OF TABLES.............................................................................................................................iii LIST OF FIGURES ...........................................................................................................................iv EXECUTIVE SUMMARY ...............................................................................................................vi I. INTRODUCTION ..................................................................................................................1 II. BACKGROUND AND DATABASE DEVELOPMENT......................................................3 Field and Laboratory Methods……………………………………………………………....3 Assessment Database ……………………………………………………………………….4 Ecoregion Reference Lake Database………………………………………………………...7 Diatom-inferred Phosphorus Database ……………………………………………………...8 USEPA Criteria Development Database…………………………………………………....10 III. CONSIDERATIONS FOR LAKE WATER QUALITY CRITERIA DEVELOPMENT ....12 Developing Criteria...............................................................................................................12 Trophic Status and Region Water Quality Patterns of Minnesota Lakes ..............................15 a. Regional patterns and TP, chlorophyll-a and Secchi interrelationships........................15 b. Regional patterns in nitrogen and TN: TP ratios...........................................................26 Lake Morphometry and Mixing Status..................................................................................28 Fisheries – Ecoregion Patterns and Effects of Eutrophication ..............................................37 Dissolved Oxygen – Fishery Effects and Internal Loading of Phosphorus...........................51 a. Dissolved oxygen, hypolimnetic oxygen depletion and internal loading ...................51 b. Dissolved oxygen and fishery effects: lake trout lakes...............................................57 Water Supply Lakes...............................................................................................................72 User Expectations..................................................................................................................79 a. User expectations and economic considerations.........................................................79 b. Lake water quality expectations and related considerations .......................................81 c. Lake user surveys........................................................................................................82 Watershed and Modeling Considerations..............................................................................86 a. Regional patterns in land use ......................................................................................86 i b. Lake modeling considerations.....................................................................................89 c. Sediment diatom reconstruction of lake trophic state .................................................95 IV. LAKE POLLUTION CONTROL PROGRAMS IN MINNESOTA.....................................99 Regulatory Programs .............................................................................................................99 Management-Grant Programs................................................................................................103 Monitoring and Education Programs.....................................................................................105 V. DERIVING EUTROPHICATION CRITERIA BY ECOREGION......................................107 General considerations for criteria development...................................................................107 a. Northern Lakes and Forests .............................................................................................112 b. North Central Hardwoods Forests ...................................................................................116 c. Western Corn Belt Plains and Northern Glaciated Plains ...............................................121 Criteria summary ...................................................................................................................125 Criteria considerations and application .................................................................................126 BIBLIOGRAPHY..............................................................................................................................131 APPENDICES ..................................................................................................................................146 I. Ecoregion reference lake data …………………………………………………………….146 II. Sediment diatom core lakes………………………………………………………………..148 III. Designated Lake Trout Lakes……………………………………………………………..150 IV. Case Studies……………………………………………………………………………….152 ii LIST OF TABLES Page Table 1. Distribution of trophic state and lake morphometric variable by ecoregion ............17 Table 2. Distribution of reference lake water quality variables by ecoregion ........................18 Table 3. Morphometric characteristics of dimictic, intermittent and continuously mixing lakes..............................................................................................................29 Table 4. Distribution of total phosphorus concentrations by lake mixing type and ecoregion............................................................................................................33 Table 5. Water quality and habitat considerations for five freshwater fish ............................42 Table 6. Trophic status summary for lake trout lakes.............................................................58 Table 7. Trophic status summary for stream trout lakes.........................................................72 Table 8. Tabulation of communities using lakes as domestic water supplies.........................76 Table 9. Lake Observer survey ...............................................................................................83 Table 10. Geometric mean Secchi relative to user perceptions by ecoregion ..........................85 Table 11a. Land use patterns by ecoregion.................................................................................87 Table 11b. Typical land use composition for lakes in ecoregion data set ..................................88 Table 12. IQ range of stream water quality ..............................................................................89 Table 13. Commonly used limnological abbreviations ............................................................91 Table 14. Ecoregion variables for MINLEAP development.....................................................92 Table 15. Calibrated stream phosphorus concentration by ecoregion ......................................93 Table 16. Ranges of monitored stream total phosphorus by ecoregion....................................95 Table 17. Comparison of diatom-inferred and observed TP by ecoregion...............................98 Table 18. Comparison of number of lakes in MPCA and EPA data sets ...............................110 Table 19. Shallow lakes summary of morphometric, water quality and plant metric ...........120 Table 20. Proposed eutrophication criteria by ecoregion and lake type .................................125 Table 21. Trophic status thresholds for determination of use support in lakes ......................127 Table 22. Percent of lakes above or below proposed TP criteria............................................129 Table 23. Percent of lakes above or below proposed Secchi criteria......................................129 iii
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