Minnehaha Creek Subwatershed Plan Minnehaha Creek Watershed District Water Resources Management Plan April 2007 Table Of Contents 1.0 INTRODUCTION AND SUMMARY............................................................................... 1 2.0 LAND AND WATER RESOURCES INVENTORY ........................................................ 2 2.1 Location .......................................................................................................................... 2 2.2 Physical Environment ..................................................................................................... 2 2.2.1 Topography and Drainage....................................................................................... 2 2.2.2 Geology and Soils................................................................................................... 2 2.2.3 Unique Features and Scenic Areas ......................................................................... 3 2.3 Biological Environment.................................................................................................. 3 2.3.1 Vegetation............................................................................................................... 3 2.3.2 Biologic Integrity.................................................................................................... 6 2.4 Human Environment....................................................................................................... 8 2.4.1 Present Land Use .................................................................................................... 8 2.4.2 2020 and 2030 Land Use Planning ......................................................................... 8 2.4.3 Aquatic Recreation.................................................................................................. 8 2.5 Hydrologic Systems...................................................................................................... 18 2.5.1 Lakes..................................................................................................................... 19 2.5.2 Streams.................................................................................................................. 21 2.5.3 Ditches .................................................................................................................. 23 2.5.4 Wetlands ............................................................................................................... 24 2.5.5 Floodplain ............................................................................................................. 31 2.5.6 Groundwater ......................................................................................................... 31 3.0 PROBLEMS AND ISSUES ............................................................................................. 35 3.1 Water Quality................................................................................................................ 35 3.2 Water Quantity.............................................................................................................. 36 3.3 Wetlands ....................................................................................................................... 36 3.4 Ecological Integrity....................................................................................................... 37 3.5 Groundwater ................................................................................................................. 37 3.6 Impacts of Future Growth............................................................................................. 38 4.0 RESOURCE MANAGEMENT GOALS AND STRATEGIES....................................... 41 4.1 Infiltration/Filtration ..................................................................................................... 41 4.2 Ecological Integrity....................................................................................................... 43 4.3 Water Quality................................................................................................................ 46 4.4 Public Health................................................................................................................. 48 4.5 Water Quantity .............................................................................................................. 49 4.6 Shorelines and Streambanks ......................................................................................... 52 4.7 Navigation ..................................................................................................................... 54 4.8 Best Management Practices .......................................................................................... 55 4.9 Education and Communications ................................................................................... 56 4.10 Ditches .......................................................................................................................... 57 4.11 Wetlands ....................................................................................................................... 58 4.12 Groundwater ................................................................................................................. 59 4.13 Floodplains .................................................................................................................... 61 4.14 Recreation ..................................................................................................................... 62 4.15 Erosion Control ............................................................................................................. 63 4.16 Regulation ..................................................................................................................... 65 4.17 Public Involvement ....................................................................................................... 66 5.0 IMPLEMENTATION PROGRAM .................................................................................. 69 5.1 Regulatory Program ...................................................................................................... 69 5.2 Land Conservation Program ......................................................................................... 70 5.3 Education Program........................................................................................................ 70 5.4 Monitoring and Data Collection ................................................................................... 71 5.5 Operations and Maintenance......................................................................................... 71 5.6 LGU Requirements ....................................................................................................... 72 5.6.1 Local Government Unit Subwatershed Phosphorus Load Reductions ..................... 72 5.6.2 Land Conservation .................................................................................................... 73 5.6.3 Other Issues ............................................................................................................... 73 5.7 Phosphorus Load Reduction ......................................................................................... 73 5.8 Capital Improvement Program ...................................................................................... 79 5.8.1 Minnehaha Creek Diagnostic Study/TMDL ............................................................. 80 5.8.2 Minnehaha Creek Stream Restoration ...................................................................... 81 5.8.3 Minnehaha Falls/ Glen Restoration .......................................................................... 87 5.8.4 Lake Nokomis Internal Load Management .............................................................. 87 5.8.5 Regional Volume and Load Reducation ................................................................... 88 5.8.6 Land Conservation .................................................................................................... 92 5.8.7 Browndale Dam Scour Repair .................................................................................. 93 5.8.8 Maintenance Projects ................................................................................................ 94 5.8.9 Other Projects............................................................................................................ 94 5.8.10 Taft-Legion Lake Regional Volume and Load Reduction……………………….97-a 5.9 Summary ....................................................................................................................... 97 TABLES Table 1. Rare species in the Minnehaha Creek subwatershed....................................................... 6 Table 2. DNR fish survey data....................................................................................................... 6 Table 3. Percent of Minnehaha Creek subwatershed by 2000 land use......................................... 8 Table 4. Public Waters in the Minnehaha Creek subwatershed................................................... 18 Table 5. Modeled peak discharge from the Minnehaha Creek subwatershed (cfs)..................... 19 Table 6. Physical characteristics of lakes in the Minnehaha Creek subwatershed. ..................... 19 Table 7. Selected water quality goals and current conditions of lakes in the Minnehaha Creek subwatershed. ...............................................................................................................