An Ecological Assessment of the Potomac River Direct Drains Watershed Report number - 02070004 - January 2005 Prepared by: Watershed Assessment Section Watershed Branch Division of Water and Waste Management West Virginia Department of Environmental Protection 601 57th Street, SE Charleston, WV 25304 www.wvdep.org 2 An Ecological Assessment Of Table Of Contents Summary ........................................................................................................................ 5 Acknowledgements ........................................................................................................ 7 Watersheds And Their Assessment................................................................................. 8 General Watershed Assessment Strategy ................................................................... 9 Probabilistic (Random) Sampling ................................................................................ 11 Watershed Assessment Methods................................................................................... 13 Biological Monitoring — Benthic Macroinvertebrates............................................ 13 West Virginia Stream Condition Index.................................................................... 17 Fecal Coliform Bacteria .......................................................................................... 19 Physicochemical Sampling ..................................................................................... 19 Habitat Assessment.................................................................................................. 21 Data Interpretation .................................................................................................. 23 The Potomac River Direct Drains Watershed............................................................... 26 Assessment Results ...................................................................................................... 33 General Overview ................................................................................................... 33 Benthic Macroinvertebrates..................................................................................... 33 Comparable Sites ............................................................................................... 33 Non-comparable Sites........................................................................................ 34 Fecal Coliform Bacteria .......................................................................................... 34 Physicochemical Water Quality............................................................................... 34 Physical Habitat....................................................................................................... 39 Results by sub-watershed ....................................................................................... 40 Back Creek Sub-watershed................................................................................ 40 Sleepy Creek Sub-watershed ............................................................................. 41 Opequon Creek Sub-watershed......................................................................... 42 Miscellaneous Streams ....................................................................................... 44 Implications ................................................................................................................. 47 References .................................................................................................................... 49 Glossary ....................................................................................................................... 52 Appendix A- Data Tables ............................................................................................. 57 The Potomac River Direct Drains Watershed 3 List Of Illustrations Figure 1. A generalized watershed............................................................................... 10 Figure 2. Common benthic macroinvertebrate organisms .......................................... 14 Figure 3. Benthos collection nets ................................................................................ 15 Figure 4. Illustration of embeddedness ....................................................................... 23 Figure 5. Stream with and without riparian buffer zone ............................................. 23 Figure 6. Example sub-watershed ............................................................................... 24 Figure 7. Example X-Y graph ..................................................................................... 25 Figure 8. West Virginia’s watersheds .......................................................................... 26 Figure 9. Limestone areas of the Potomac River Direct Drains watershed ................. 27 Figure 10. Ecoregions of the Potomac River Direct Drains watershed ....................... 28 Figure 11. Landuses in the Potomac River Direct Drains watershed .......................... 30 Figure 12. WVSCI scores at each sample site ............................................................. 35 Figure 13. Back Ck. WVSCI scores vs. RBP habitat scores ...............................................36 Figure 14. Sleepy Ck. WVSCI scores vs. RBP habitat scores.............................................36 Figure 15. Opequon Ck. WVSCI scores vs. RBP habitat scores.........................................37 Figure 16. Miscellaneous streams WVSCI scores vs. RBP habitat scores...........................37 Figure 17. Fecal coliform bacteria levels .................................................................... 38 Figure 18. Back Creek................................................................................................. 40 Figure 19. Sleepy Creek .............................................................................................. 41 Figure 20. Opequon Creek.......................................................................................... 43 Figure 21. Miscellaneous streams................................................................................ 45 Figure 22. Karst........................................................................................................... 46 4 An Ecological Assessment Of List Of Tables Table 1. Water quality parameters ............................................................................... 20 Table 2. Scoring for rapid habitat assessment ............................................................. 22 Table 3. 2002 303(d) list streams .......................................................................................32 Table 4. Streams on both the 303(d) list and the WVDNR high quality streams list ..............32 Table 5. Streams on the proposed special waters list .................................................32 Table 6. Sampling summary ........................................................................................ 34 Table 7. Sites with nitrite+nitrate nitrogen > 1.0 mg/l ................................................39 Table 8. Back Creek sub-watershed ..................................................................................40 Table 9. Sleepy Creek sub-watershed ................................................................................41 Table 10. Opequon Creek sub-watershed .........................................................................42 Table 11. Miscellaneous streams ........................................................................................44 Table 12. Miscellaneous streams sub-watershed landuse area percentages .........................45 Table 13. Major sub-watershed landuses ...........................................................................46 Table A-1. Sites Sampled ............................................................................................ 58 Table A-2. Physical characteristics of 100 meter stream reach .................................... 60 Table A-3. Observed sediment characteristics............................................................. 62 Table A-4. Substrate composition in benthic collection area ...................................... 64 Table A-5. Macrobenthic community metrics and WVSCI scores .............................. 66 Table A-6. Numbers of each taxon found at each sample site ....................................68 Table A-7. Water quality parameters measured in the field, and fecal coliform bacteria.................................................................................................................... 81 Table A-8. Additional water quality parameters taken from a subset of all streams sampled ................................................................................................................... 83 Table A-9. Additional water quality parameters taken from a subset of all streams sampled ................................................................................................................... 84 Table A-10. Rapid Habitat Assessment Scores ............................................................ 86 The Potomac River Direct Drains Watershed 5 Summary In June of 1998, the West Virginia Department of Environmental Protection conducted an assessment of the Potomac River Direct Drains watershed, located in the eastern panhandle of the state. The watershed includes all West Virginia tributaries to the river between the South Branch and Shenandoah River exclusive of those two