Baseline Watershed Assessment Pequonnock River Watershed City of Bridgeport September 2010 In Cooperation With: Pequonnock River Initiative Project No. 20090730.A10 Table of Contents Baseline Watershed Assessment Pequonnock River Watershed 1 Introduction .................................................................................1 1.1 Development of the Baseline Assessment Report ....................................................2 1.2 Background .....................................................................................................................3 1.3 Watershed Stewardship Efforts....................................................................................6 2 Study Area Description...............................................................9 2.1 Municipal Jurisdictions ..................................................................................................9 2.2 Pequonnock River Watershed ....................................................................................10 2.3 Subwatersheds...............................................................................................................12 3 Historical and Social Perspective............................................13 3.1 History of the Watershed ............................................................................................13 3.2 Population and Demographics...................................................................................20 3.3 Historical Resources.....................................................................................................23 3.4 Recreation and Community Resources .....................................................................26 4 Natural Resources.....................................................................28 4.1 Geology and Soils.........................................................................................................28 4.2 Topography...................................................................................................................28 4.3 Hydrology......................................................................................................................32 4.4 Flood Hazard Areas .....................................................................................................35 4.5 Climate ...........................................................................................................................37 4.6 Wetlands ........................................................................................................................38 4.6.1 Resource Description.....................................................................................38 4.6.2 Existing Wetlands Information ....................................................................40 4.7 Fish and Wildlife Resources........................................................................................42 4.7.1 Fish....................................................................................................................42 4.7.2 Birds..................................................................................................................44 4.7.3 Amphibians & Reptiles ..................................................................................44 4.7.4 Threatened and Endangered Species...........................................................45 5 Watershed Modifications..........................................................48 5.1 Dams and Impoundments ..........................................................................................48 5.2 Water Supply.................................................................................................................50 5.3 Wastewater ....................................................................................................................51 5.4 Stormwater ....................................................................................................................51 5.4.1 Municipal Phase II Stormwater Program....................................................53 5.4.1.1 Bridgeport .......................................................................................53 5.4.1.2 Trumbull ........................................................................................54 5.4.1.3 Monroe...........................................................................................54 F:\P2009\0730\A10\Baseline Watershed Assessment\Baseline Watershed Assessment.doc i Table of Contents Baseline Watershed Assessment Pequonnock River Watershed 5.5 Regulated Sites ..............................................................................................................54 6 Water Quality .............................................................................59 6.1 Classification, Standards, and Impairments..............................................................59 6.2 CTDEP Ambient Water Quality Monitoring Program..........................................65 6.2.1 Monitoring Program.......................................................................................65 6.2.2 Metals................................................................................................................67 6.2.3 Nutrients ..........................................................................................................68 6.2.4 Benthic Macroinvertebrates ..........................................................................68 6.3 Harbor Watch / River Watch Water Quality Monitoring Program .....................70 6.4 City of Bridgeport CSO Receiving Water Monitoring Program ...........................77 7 Land Use and Land Cover ........................................................79 7.1 Current Conditions ......................................................................................................79 7.1.1 Land Use ..........................................................................................................79 7.1.2 Zoning ..............................................................................................................81 7.1.3 Land Cover ......................................................................................................83 7.1.4 Forest Cover....................................................................................................86 7.1.4.1 Forest Fragmentation......................................................................87 7.1.5 Developed Areas.............................................................................................88 7.1.6 Impervious Cover...........................................................................................91 7.1.7 Open Space......................................................................................................95 7.2 Future Conditions ........................................................................................................98 7.2.1 Watershed Buildout Analysis ........................................................................98 7.2.1.1 Developable Land and Future Land Use ........................................98 7.2.1.2 Impervious Cover.......................................................................... 100 8 Pollutant Loading ....................................................................103 8.1 Model Description..................................................................................................... 103 8.2 Model Inputs.............................................................................................................. 104 8.2.1 Nonpoint Source Runoff............................................................................ 104 8.2.2 Other Pollutant Sources.............................................................................. 104 8.2.2.1 Combined Sewer Overflows........................................................... 104 8.2.2.2 Illicit Discharges........................................................................... 105 8.2.2.3 Septic Systems.............................................................................. 105 8.2.2.4 Managed Turf.............................................................................. 105 8.2.2.5 Road Sanding.............................................................................. 105 8.3 Existing Pollutant Loads .......................................................................................... 106 8.4 Future Pollutant Loads............................................................................................. 108 9 Comparative Subwatershed Analysis ...................................110 F:\P2009\0730\A10\Baseline Watershed Assessment\Baseline Watershed Assessment.doc ii Table of Contents Baseline Watershed Assessment Pequonnock River Watershed 9.1 Priority Subwatersheds for Conservation .............................................................. 110 9.2 Priority Subwatersheds for Restoration ................................................................. 113 9.3 Subwatersheds Recommended for Field Assessments ........................................ 116 10 References...............................................................................119 Tables Page 2-1 Distribution of Municipalities in the Pequonnock River Watershed 9 2-2 Profile of the Pequonnock River Watershed 11 2-3 Pequonnock River Subwatersheds 12 3-1 National and State Register of Historic Places and Local Historic Districts 25 4-1 Miles of Mapped Streams Within Each Subwatershed 32 4-2 Peak Flow Frequency