The Status of Water Quality in the Rivers and Tributaries of the Shenandoah River Watershed Final Report (Third Edition) August, 2007 A paper prepared by Charles Vandervoort of the Friends of the Shenandoah River with the cooperation of the Volunteer Monitors of the Shenandoah River Watershed. Table of Contents Foreword .............................................................................................................................................................................................v Executive Summary ..........................................................................................................................................................................vii Acknowledgments..............................................................................................................................................................................xi Chapter 1: Introduction.....................................................................................................................................................................1 Purpose ........................................................................................................................................................................................1 Background..................................................................................................................................................................................1 Methodology ...............................................................................................................................................................................3 Water Quality Criteria .................................................................................................................................................................3 Findings........................................................................................................................................................................................3 Chapter 2: Overview of Water Quality in Rivers, Tributaries, and STPs in the Counties of the Shenandoah River Watershed.....................................................................................................................................................5 A: Water Quality by County in 2006 .........................................................................................................................................5 B: Water Quality in 1997 compared with 2006........................................................................................................................6 Chapter 3: The Trends in Water Quality...........................................................................................................................................9 A: Trend for Nitrogen in Rivers and in Tributaries ...................................................................................................................9 Trend for Nitrogen in Rivers................................................................................................................................................9 Trend for Nitrogen in Tributaries......................................................................................................................................12 B: Trend for Turbidity in Rivers and in Tributaries.................................................................................................................12 Trend for Turbidity in Rivers .............................................................................................................................................12 Trend of Turbidity in Tributaries.......................................................................................................................................13 C: Water Quality in Each Section of the River, and by Year...................................................................................................14 Average Nitrogen Levels by River Section.........................................................................................................................15 Average Turbidity Levels by River Section ........................................................................................................................16 Average Ammonia Levels by River Section .......................................................................................................................18 Average pH Levels by River Section...................................................................................................................................19 Average Phosphorus Levels by River Section....................................................................................................................19 Average Dissolved Oxygen Levels by River Section ..........................................................................................................21 Chapter 4: Most and Least Impaired Sites of the River and Tributaries, 2006 ............................................................................23 A: River Sites ..............................................................................................................................................................................23 B: Tributary Sites .......................................................................................................................................................................25 C: Past History Of Nitrogen And Turbidity For Most Impaired Sites....................................................................................26 D: Sewage Treatment Plants (STPs) .........................................................................................................................................26 Chapter 5: Reasons for the High Pollution and the Growing Trend in Pollution ......................................................................29 A: Non-point source pollution.................................................................................................................................................29 B: Point-source pollution .........................................................................................................................................................29 C: Land use changes and population growth..........................................................................................................................29 Some photos illustrating the issues above .......................................................................................................................30 Some of the reasons...........................................................................................................................................................30 Stream Restoration – it works! ..........................................................................................................................................31 Photos taken during aerial surveys in 2004 and 2007 ....................................................................................................34 Chapter 6: Prospects for stopping and reversing degradation of the river...................................................................................39 A: Areas where progress is being made....................................................................................................................................39 B: Areas where progress is slow................................................................................................................................................40 iii Chapter 7: Mercury Contamination in the South River and South Fork of the Shenandoah River ..........................................43 Chapter 8: Fish Kills in the Shenandoah Watershed .....................................................................................................................45 Chapter 9: Appendices.....................................................................................................................................................................47 A: Methodology.........................................................................................................................................................................47 Selection of the Sampling Sites .........................................................................................................................................47 B: Statistical Considerations.....................................................................................................................................................48 Simple versus weighted averages.......................................................................................................................................48 Frequency of monitoring...................................................................................................................................................48 Interdependence.................................................................................................................................................................49 C: Water Quality Parameters Measured by the FOSR and Supporting Organizations, and Suggested Standards..............49 Nutrients .............................................................................................................................................................................49 Dissolved Oxygen, Acidity, and Turbidity