South Branch Patapsco River Watershed Characterization Plan Spring 2016 Prepared by Carroll County Bureau of Resource Management South Branch Patapsco Watershed Characterization Plan Table of Contents List of Figures ................................................................................................................................ iv List of Tables ................................................................................................................................. iv List of Appendices .......................................................................................................................... v List of Acronyms ........................................................................................................................... vi I. Characterization Introduction ................................................................................................. 1 A. Purpose of the Characterization ....................................................................................... 1 B. Location and Scale of Analysis ........................................................................................ 1 C. Report Organization ......................................................................................................... 3 II. Natural Characteristics ............................................................................................................ 5 A. Introduction ...................................................................................................................... 5 B. Climate ............................................................................................................................. 5 C. Physical Location ............................................................................................................. 7 1. Topography ................................................................................................................... 7 2. Soils ............................................................................................................................ 10 a. Hydrologic Soil Groups .......................................................................................... 10 3. Geology ...................................................................................................................... 13 D. Surface Water Resources ............................................................................................... 15 1. Wetlands ..................................................................................................................... 15 2. Floodplains ................................................................................................................. 18 3. Forest .......................................................................................................................... 20 a. Forest Cover ............................................................................................................ 20 E. Ecologically Important Areas......................................................................................... 22 F. Groundwater Resources ................................................................................................. 24 III. Human Characteristics ...................................................................................................... 25 A. Population....................................................................................................................... 25 B. Baseline and Current Land Cover .................................................................................. 25 C. Priority Funding Areas, Zoning and Build Out .............................................................. 28 1. Priority Funding Areas ............................................................................................... 28 2. Zoning and Build-Out ................................................................................................. 28 D. Impervious Surfaces ....................................................................................................... 32 E. Stormwater ..................................................................................................................... 34 1. Stormwater Management Facilities ............................................................................ 34 2. Storm Drain Systems .................................................................................................. 35 F. Drinking Water ............................................................................................................... 37 1. Wellhead Protection Areas ......................................................................................... 37 2. Public Water Service Area ......................................................................................... 37 3. Water Supply .............................................................................................................. 37 G. Wastewater ..................................................................................................................... 39 1. Public Wastewater Service Area ................................................................................ 39 2. Wastewater Discharge Locations ............................................................................... 39 3. On-Site Septic Systems .............................................................................................. 40 ii South Branch Patapsco Watershed Characterization Plan H. NPDES Point Sources .................................................................................................... 42 I. Protected Lands .............................................................................................................. 43 1. Rural Legacy Program ................................................................................................ 43 J. Agricultural Best Management Practices ....................................................................... 47 1. Farm Plan Acres ......................................................................................................... 47 IV. Water Quality .................................................................................................................... 49 A. Introduction .................................................................................................................... 49 B. Designated Uses ............................................................................................................. 49 C. Tier II Waters ................................................................................................................. 50 D. Total Maximum Daily Loads ......................................................................................... 50 1. Current Impairments ................................................................................................... 50 E. Water Quality Data......................................................................................................... 52 1. Current Monitoring ..................................................................................................... 52 2. Maryland Biological Stream Survey .......................................................................... 54 a. Maryland’s DNR Results ........................................................................................ 54 V. Living Resources .................................................................................................................. 59 A. Introduction .................................................................................................................... 59 B. Aquatic Biology ............................................................................................................. 59 1. Index of Biotic Integrity ............................................................................................. 60 a. Maryland’s DNR Results ........................................................................................ 60 b. Carroll County Results ............................................................................................ 62 C. Sensitive Species ............................................................................................................ 66 1. Rare, Threatened and Endangered Species ................................................................. 66 D. Stream Corridor Assessment .......................................................................................... 66 1. Subwatershed Summary ............................................................................................. 71 VI. Characterization Summary ................................................................................................ 73 A. Summary ........................................................................................................................ 73 B. Cost Summary ................................................................................................................ 73 VII. References: ........................................................................................................................ 74 iii South Branch Patapsco Watershed Characterization Plan List of Figures Figure 1-1 South Branch Patapsco Watershed Location Map ........................................................ 2 Figure 2-1 South Branch Patapsco Subwatershed Locations ........................................................