WATER QUALITY IN THE KETTLE CREEK WATERSHED: A SUMMARY OF 1991-1995 CONDITIONS AND TRENDS Prepared by: Susan Evans Water Quality Specialist Grand River Conservation Authority & Tim Lanthier Water Conservation Supervisor Kettle Creek Conservation Authority December 2006 Kettle Creek Conservation Authority Page ii TABLE OF CONTENTS TABLE OF CONTENTS ...................................................................... II LIST OF FIGURES ........................................................................... IV LIST OF TABLES .............................................................................. V LIST OF APPENDICES ...................................................................... V EXECUTIVE SUMMARY ..................................................................... 6 INTRODUCTION................................................................................ 8 Watershed Characteristics.....................................................................8 Major Water Uses ....................................................................................9 METHODS ..................................................................................... 14 Dataset Selection ..................................................................................14 Parameters Analysed............................................................................15 Routine Chemistry, Nutrients, Metals and Pesticides ....................15 Bacteria and Pathogens.....................................................................16 Reservoirs...........................................................................................16 Data Analysis.........................................................................................16 Streamflow ..........................................................................................16 Summary Statistics ............................................................................17 Comparative Statistics.......................................................................17 Compliance with Guidelines..............................................................18 Trend analysis (LOWESS) .................................................................18 RESULTS ...................................................................................... 19 Streamflow.............................................................................................19 Sampling Frequency.............................................................................19 Water Quality Conditions 1991-1995 ...................................................21 Nitrate ..................................................................................................21 Nitrite ...................................................................................................22 Ammonia .............................................................................................23 Total Kjeldahl Nitrogen ......................................................................24 Phosphorus ........................................................................................25 Non-Filterable Residue (NFR)............................................................26 Chloride...............................................................................................27 Correlation between Flow and Nutrients..........................................28 pH.........................................................................................................29 Dissolved Oxygen ..............................................................................29 Temperature........................................................................................29 Metals ..................................................................................................31 Pesticides............................................................................................31 Page iii Bacteria and Pathogens.....................................................................31 Preliminary Trend Analysis (LOWESS Plots) .....................................33 REVIEW OF EXISTING LITERATURE ................................................. 36 Benthic Macroinvertebrate Monitoring ...............................................36 General Bacterial Conditions within all Sub-basins ..........................37 Monitoring of PAH Contamination in Port Stanley ............................37 DISCUSSION.................................................................................. 38 Data Limitations ....................................................................................38 Data Quantity Limitations..................................................................38 Data Quality Limitations ....................................................................39 Water Quality Conditions in the Kettle Creek watershed ..................39 General Physiochemical Conditions within all Sub-basins ...........40 Conditions Specific to the Upper Kettle Creek Sub-basin .............40 Conditions Specific to the Dodd Creek Sub-basin..........................42 Conditions Specific to the Lower Kettle Creek Sub-basin .............43 Trends in Water Quality........................................................................45 Spills.......................................................................................................45 SUMMARY & CONCLUSIONS........................................................... 46 RECOMMENDATIONS ..................................................................... 48 Sampling Regime ..................................................................................48 Monitoring..............................................................................................48 Reporting ...............................................................................................48 Future Investigations............................................................................49 REFERENCES................................................................................ 50 APPENDICES................................................................................. 53 LIST OF FIGURES Figure 1. Kettle Creek watershed characteristics illustrating location of: urban centres, industrial areas, wastewater treatment plants, drinking water intakes, streams, & reservoirs..........................................10 Figure 2. Location of the 7 long-term monitoring stations from the Provincial Water Quality Monitoring Network (PWQMN) within the 3 major sub-basins within the Kettle Creek watershed: Upper Kettle Creek (grey), Dodd Creek (blue) and Lower Kettle Creek (green). ............................................11 Figure 3. Surficial Materials of the Kettle Creek watershed............................................................................12 Figure 4. Land cover in the Kettle Creek watershed........................................................................................13 Figure 5. Location of the 7 long-term monitoring sites from the Provincial Water Quality Monitoring Network (PWQMN) analysed in this study............................................................................................15 Figure 6. Location of flow stations monitored by the Water Survey of Canada within the Kettle Creek watershed................................................................................................................................................17 Figure 7. Box and whisker plot illustrating the 5th, 25th, 50th (median), 75th and 95th percentiles and outliers of the 1991-1995 dataset............................................................................................................17 Figure 8. Flow rates at the three Water Survey of Canada gauge stations for the period from 1991-1995 within Kettle Creek watershed. ..............................................................................................................20 Figure 9. Average annual stream flow from 1967-2004 for station 02GC002 at St. Thomas. ........................20 Figure 10. Daily stream flow rates at three locations within the Kettle Creek watershed plotted with the time of sampling events..........................................................................................................................21 Figure 11. Total Nitrate concentrations at 7 PWQMN monitoring sites in the Kettle Creek watershed from 1991-1995......................................................................................................................................22 Figure 12. Total Nitrite concentrations at 7 PWQMN monitoring sites in the Kettle Creek watershed from 1991-1995...............................................................................................................................................23 Figure 13. Unionized Ammonia concentrations at 7 PWQMN monitoring sites in the Kettle Creek watershed from 1991-1995.....................................................................................................................24 Figure 14. Total kjeldahl nitrogen concentrations at 7 PWQMN monitoring sites in the Kettle Creek watershed from 1991-1995.....................................................................................................................25 Figure 15. Total Phosphorus concentrations at 7 PWQMN monitoring sites in the Kettle Creek watershed from 1991-1995......................................................................................................................................26