Watershed Action Plan December 2002 Mission Watersheds Statement To protect, sustain, and enhance the quality and quantity of all water resources to insure the health, safety, and welfare of the citizens, and preserve the diverse natural resources and aesthetic and recreational assets of Chester County and its watersheds. Disclaimer The maps, data and information presented herein were compiled by the Chester County Water Resources Authority for the County of Chester, PA and are hereby referenced to the Chester County, Pennsylvania Water Resources Compendium (2001). These information and data are pro- vided for reference and planning purposes only. This document is based on and presents the best information available at the time of the preparation. Funding Partners Chester County and the Chester County Water Resources Authority express their appreciation to those entities who provided financial support for this effort. This project was funded by: • Chester County Board of Commissioners. • Pennsylvania Department of Conservation and Natural Resources, Bureau of Recreation and Conservation, Keystone Recreation, Park and Conservation Fund Program. • Pennsylvania Department of Environmental Protection, and U. S. Environmental Protection Agency Nonpoint Source Pollution Management Program. • Brandywine Valley Association and William Penn Foundation. • U. S. Geological Survey. Chester County Board of Commissioners Karen L. Martynick, Chairman Colin A. Hanna Andrew E. Dinniman Watershed Action Plan December 2002 Prepared by: Chester County Water Resources Authority Chester County Planning Commission Camp Dresser and McKee Gaadt Perspectives, LLC Prepared as a component of: Chester County, Pennsylvania Water Resources Compendium _________________________ Prepared under a Nonpoint Source Pollution Management Grant funded by Pennsylvania Department of Environmental Protection and U. S. Environmental Protection Agency Table of Contents Acknowledgements ................................................................................................................ iv Section 1. Watershed Setting ..................................................................................................1 Section 2. Planning Framework..............................................................................................3 Section 3. Watershed Characteristics ....................................................................................5 Population ......................................................................................................................5 Land Use .......................................................................................................................5 Impervious Cover...........................................................................................................5 Geology .........................................................................................................................5 Watershed Water Budgets..............................................................................................6 Ground Water Balances .................................................................................................6 Ground Water Quality ...................................................................................................8 Stream Water Quality ....................................................................................................9 State Water Protected Use Designations........................................................................9 Stream Water Quality Assessments – Impaired Waters ..............................................10 Total Maximum Daily Load Regulations ....................................................................10 Nonpoint Source Pollutant Loads ................................................................................10 National Pollutant Discharge Elimination System (NPDES) Phase II Regulations....10 Biological Diversity Monitoring..................................................................................11 Pennsylvania Natural Diversity Index (PNDI) ............................................................11 Cultural, Recreational and Historic Resources ............................................................12 First Order Streams......................................................................................................12 Land Use Analysis within Stream Corridors ...............................................................12 Sources of Water Supplies...........................................................................................13 Surface Water Withdrawals and Discharges................................................................13 Integrated Water Resources Planning to Meet Future Needs .....................................14 Section 4. Watershed Management Needs and Priorities ..................................................16 Inventory of Watershed Management Needs...............................................................16 Watershed and Subbasin Priorities ..............................................................................16 Section 5. Priority Watershed Management Objectives and Actions ...............................19 Goals and Objectives ...................................................................................................19 Recommended Priority Management Actions.............................................................20 Other Recommended Management Actions ................................................................20 Ongoing Initiatives.......................................................................................................20 Section 6. Indicators of Progress ..........................................................................................21 Landscapes Indicators .................................................................................................21 Watersheds Indicators .................................................................................................21 Section 7. References .............................................................................................................22 Octoraro Creek Watershed Action Plan i Tables 1 Subbasins within the Watershed 2 Snapshot of Watershed Characteristics 3 Population – 1998 Estimates and 2020 Projections by Subbasin 4 Land Use in the Watershed 5 Percent Impervious Cover by Subbasin 6 Estimated 1998 Net Ground Water Withdrawals by Subbasin 7 Protected Water Use Designations 8 Listing of Impaired Streams 9 Average Yearly Brillouin’s Diversity Index Values for the Watershed 10 PNDI Sites Located Within the Watershed 11 Inventory of Mapped Recreational Resources 12 Inventory of Mapped Historic Resources 13 First Order Stream Miles 14 Drainage Areas to First Order Streams 15 Land Use Within Corridors of First Order Streams 16 Land Use Within Corridors of Higher Order Streams 17 Estimated Average Annual Water Withdrawals and Future Needs by Subbasin – 1998 and 2020 18 List of Small Community Water Systems (shown on Figure 22) 19 Inventory of Watershed Management Needs 20 Subbasin Priorities 21 Recommended Priority Management Actions 22 Components of the Landscapes Index 23 New Watersheds Indicators for Landscapes Index Figures 1 Basemap of Watershed 2 Subbasins 3 Municipalities within the Watershed 4 Inventory of Problems and Potential Concerns 5 Stream Resources and Competing Uses 6 1995 Land Use 7 Estimated Percent Impervious Cover in Subbasins - 1998 8 Generalized Geology 9 1998 Net Ground Water Withdrawals as a Percent of the 1 in 25 Year Average Annual Baseflow 10 2020 Net Ground Water Withdrawals as a Percent of the 1 in 25 Year Average Annual Baseflow 11 State Protected Water Use Designations 12 Municipalities Required to Implement NPDES Phase II Regulations 13 Location of USGS Biological Monitoring Sites 14 Cultural, Recreational and Historic Resources 15 Drainage Areas of First Order Streams 16 Land Use Within One-Quarter Mile Corridor of First Order Streams 17 Land Use Within One-Quarter Mile Corridor of Higher Order Streams ii Octoraro Creek Watershed Action Plan Figures (continued) 18 Recommended Integrated Water Resources Planning Regions 19 Recommended Net Ground Water Withdrawal Management Thresholds 20 Chester County Areas of Planned Growth and Future Needs - Water 21 Chester County Areas of Planned Growth and Future Needs - Wastewater 22 Community Water Supply Systems Operating Within or Near Chester County Appendices A Water Balance Data Sheet B Watershed and Subbasin Data Sheets C Watershed and Subbasin Nonpoint Source Loadings Data Sheets D Additional Recommendations of Management Actions E Ongoing Initiatives Octoraro Creek Watershed Action Plan iii Section 1. Watershed Setting The Octoraro Creek watershed has several primary characteristics that lay the foundation for the priority management needs: S The land use of the watershed is primarily represented by agricultural and wooded lands. S The watershed is a source of public drinking water supplies for portions of Chester and Delaware Counties, Pennsylvania and New Castle County, Delaware. S The entire Octoraro Creek watershed is listed in Watersheds as a regional high priority for water quality restoration due to widespread elevated levels of nitrate in ground water throughout the watershed. S In certain areas, surface and ground water quality suffers from current and historic pollutant runoff from developed and agricultural lands, resulting in 37