COMPREHENSIVE POND MANAGEMENT PLAN FOR EIGHT PONDS IN WELLESLEY, MASSACHUSETTS FINAL REPORT [DRAFT] BY WATER RESOURCE SERVICES, INC. APRIL 2017 Contents 1. Introduction .......................................................................................................................................... 1 1.1 Project Background and Need ............................................................................................................ 1 1.2 Project Location .................................................................................................................................. 2 1.3 Uses and Rehabilitation Needs ........................................................................................................... 2 1.4 Presentation of Report........................................................................................................................ 6 2. Study Approach and Methods .............................................................................................................. 7 2.1 Watershed Assessment ....................................................................................................................... 7 2.2 Water Quality ...................................................................................................................................... 7 2.3 Bathymetry and Sediment Depth Distribution Assessment ............................................................... 7 2.4 Sediment Quality Assessment ............................................................................................................ 8 2.5 Plankton Analysis ................................................................................................................................ 8 2.6 Plant Assessment ................................................................................................................................ 8 2.7 Water Quality Modeling ..................................................................................................................... 9 3. All Ponds Investigative Results ............................................................................................................ 10 3.1 Morphology ....................................................................................................................................... 10 3.2 Watershed Assessment .................................................................................................................... 10 3.3 Incoming Water Quality .................................................................................................................... 11 Dry and Wet Weather Inputs .............................................................................................................. 11 Turbidity .............................................................................................................................................. 11 Specific Conductivity ........................................................................................................................... 17 Ammonium N ...................................................................................................................................... 17 Nitrate+Nitrite N ................................................................................................................................. 17 Total Kjeldahl Nitrogen ....................................................................................................................... 17 Total Nitrogen ..................................................................................................................................... 18 Dissolved Phosphorus and Total Phosphorus ..................................................................................... 18 3.4 In-Lake Water Quality ....................................................................................................................... 19 Temperature ....................................................................................................................................... 19 Dissolved Oxygen ................................................................................................................................ 19 Turbidity .............................................................................................................................................. 22 pH ........................................................................................................................................................ 22 Alkalinity .............................................................................................................................................. 22 Specific Conductivity ........................................................................................................................... 22 Secchi Transparency............................................................................................................................ 25 Nitrogen .............................................................................................................................................. 25 Phosphorus ......................................................................................................................................... 27 Nitrogen:Phosphorus Ratio ................................................................................................................. 27 3.5 Sediment Quality Assessment .......................................................................................................... 29 3.6 Plankton Analysis .............................................................................................................................. 30 3.7 Plant Assessment .............................................................................................................................. 34 4. Abbotts Pond ...................................................................................................................................... 36 4.1 Pond Features ................................................................................................................................... 36 4.2 Watershed Features .......................................................................................................................... 36 4.3 Designated Uses ................................................................................................................................ 36 4.4 Additional In-lake Investigative Results ............................................................................................ 39 Sediment Assessment ......................................................................................................................... 39 Plant Assessment ................................................................................................................................ 39 General Appearance ........................................................................................................................... 39 4.5 Nutrient Loading ............................................................................................................................... 41 4.6 Data Analysis and Interpretation ...................................................................................................... 42 4.7 Management Recommendations ..................................................................................................... 42 5. Bezanson Pond .................................................................................................................................... 43 5.1 Pond Features ................................................................................................................................... 43 5.2 Watershed Features .......................................................................................................................... 43 5.3 Designated Uses ................................................................................................................................ 43 5.4 Additional In-lake Investigative Results ............................................................................................ 46 Sediment Assessment ......................................................................................................................... 46 Plant Assessment ................................................................................................................................ 46 General Appearance ........................................................................................................................... 46 5.5 Nutrient Loading ............................................................................................................................... 46 5.6 Data Analysis and Interpretation ...................................................................................................... 49 5.7 Management Recommendations ..................................................................................................... 50 6. Duck Pond ........................................................................................................................................... 51 6.1 Pond Features ................................................................................................................................... 51 6.2 Watershed Features .........................................................................................................................