Broadkill River Watershed Management Plan Final Plan January 2015 Prepared for: Department of Natural Resources and Environmental Control (DNREC) Prepared by: KCI Technologies, Inc. 1352 Marrows Road Suite 100 Newark, DE 19711 Broadkill River Watershed Management Plan Final Plan January 2015 Prepared for: Department of Natural Resources and Environmental Control (DNREC) Prepared by: KCI Technologies, Inc. 1352 Marrows Road Suite 100 Newark, DE 19711 KCI Job Order No. 17133560 Broadkill River Watershed Management Plan 2015 Table of Contents 1 Introduction ................................................................................................................... 5 1.1 Watershed Plan Structure ............................................................................................................. 6 1.2 Regulatory and Programmatic Environment ................................................................................ 7 1.3 Watershed Priorities ..................................................................................................................... 8 2 Watershed Characteristics.............................................................................................. 8 2.1 Watershed Delineation and Planning Segments .......................................................................... 8 2.2 Broadkill River ............................................................................................................................. 10 2.3 Land Use ...................................................................................................................................... 12 2.3.1 Existing Land Use ................................................................................................................ 12 2.4 Water Quality .............................................................................................................................. 16 2.4.1 Use Designations ................................................................................................................. 16 2.4.2 303(d) Impairments ............................................................................................................ 16 2.4.3 TMDLs ................................................................................................................................. 16 2.4.4 NPDES .................................................................................................................................. 17 2.5 Anticipated Growth ..................................................................................................................... 17 3 Causes and Sources of Impairment (a) .......................................................................... 18 3.1 Impairments ................................................................................................................................ 18 3.1.1 Nutrients ............................................................................................................................. 18 3.1.2 Bacteria ............................................................................................................................... 18 3.2 Sources ........................................................................................................................................ 19 3.2.1 Wastewater ......................................................................................................................... 19 3.2.2 Urban .................................................................................................................................. 20 3.2.3 Agriculture........................................................................................................................... 20 3.2.4 Septic ................................................................................................................................... 21 3.2.5 Forest .................................................................................................................................. 22 3.3 Summary ..................................................................................................................................... 22 4 Expected Load Reductions (b) ....................................................................................... 22 4.1 Nutrients ..................................................................................................................................... 22 4.2 Bacteria ....................................................................................................................................... 24 5 Management Measures (c) ........................................................................................... 24 5.1 Nutrients ..................................................................................................................................... 25 5.1.1 Wastewater ......................................................................................................................... 25 5.1.2 Urban .................................................................................................................................. 26 5.1.3 Agriculture........................................................................................................................... 28 5.1.4 Septic ................................................................................................................................... 30 5.1.5 Forest .................................................................................................................................. 31 5.2 Bacteria ....................................................................................................................................... 31 5.3 Offsetting Nutrient and Sediment Loads from Future Growth .................................................. 33 5.3.1 Statewide Stormwater Regulations .................................................................................... 33 i DNREC Broadkill River Watershed Management Plan 2015 5.3.2 Establish in-lieu fee for stormwater impacts ...................................................................... 33 5.3.3 Establish a statewide program that provides additional flexibility for offsets ................... 33 5.3.4 Adaptive management ........................................................................................................ 33 5.4 Summary ..................................................................................................................................... 34 6 Technical and Financial Assistance Needs (d) ................................................................ 34 6.1 Wastewater ................................................................................................................................. 37 6.2 Urban .......................................................................................................................................... 37 6.3 Agriculture .................................................................................................................................. 37 6.4 Septic ........................................................................................................................................... 38 6.5 Forest .......................................................................................................................................... 38 6.6 Funding Sources .......................................................................................................................... 38 7 Public Participation / Education (e) .............................................................................. 40 7.1 Public Participation ..................................................................................................................... 40 7.2 General Outreach and Education ................................................................................................ 41 7.3 Source Sector Outreach and Education ...................................................................................... 42 7.3.1 Agriculture Outreach and Education .................................................................................. 42 7.3.2 Urban Stormwater Outreach and Education ...................................................................... 42 8 Implementation Schedule and Milestones (f & g) ......................................................... 42 8.1 Loading Allocations and Milestone Targets ................................................................................ 43 8.2 Implementation Milestones ........................................................................................................ 43 8.3 Implementation Priorities ........................................................................................................... 44 9 Load Reduction Evaluation Criteria (h) .......................................................................... 48 10 Monitoring (i) .............................................................................................................. 49 11 References ................................................................................................................... 51 List of Tables Table 1: Broadkill River Local TMDL Allocated and Planned Loads .............................................................. 6 Table 2: Broadkill River Watershed Drainage Area and Stream Miles ....................................................... 10 Table 3: Use Designations