FINAL DRAFT ENVIRONMENTAL ASSESSMENT: Wood Island Harbor and the Pool at Biddeford Environmental Assessment, Finding of No Significant Impact and Section 404(b)(1) Evaluation for Maintenance Dredging Wood Island Harbor and the Pool at Biddeford Biddeford, Maine May 2020 FINAL DRAFT ENVIRONMENTAL ASSESSMENT: Wood Island Harbor and the Pool at Biddeford ________________________________________________________________________________________________________ This page intentionally left blank ii FINAL DRAFT ENVIRONMENTAL ASSESSMENT: Wood Island Harbor and the Pool at Biddeford ________________________________________________________________________________________________________ TABLE OF CONTENTS FINDING OF NO SIGNIFICANT IMPACT ................................................................................ 1 1.0 Introduction ......................................................................................................................... 4 1.1 Purpose and Need ........................................................................................................ 4 1.2 Proposed Action ............................................................................................................ 5 2.0 Authority and Dredge History .......................................................................................... 9 3.0 Alternatives ......................................................................................................................... 9 3.1 No Action Alternative .................................................................................................. 10 3.2 Maintaining Channel at Authorized Dimensions ..................................................... 10 3.3 Alternate Dredging Methods ...................................................................................... 10 3.3.1 Mechanical Bucket Dredge ..................................................................................... 11 3.3.2 Hydraulic Cutterhead Pipeline Dredge .................................................................. 11 3.3.3 Hopper Dredge .......................................................................................................... 12 3.4 Disposal Alternatives .................................................................................................. 12 3.4.1 Beach Renourishment .............................................................................................. 12 3.4.2 Nearshore Placement .......................................................................................... 13 3.4.3 Upland Placement ................................................................................................ 14 3.4.4 Open Water Placement ....................................................................................... 14 3.4.5 Stratton Island Expansion ................................................................................... 15 4.0 Environmental Setting .................................................................................................... 16 4.1 General .......................................................................................................................... 16 4.2 Water Quality .................................................................................................................. 17 4.2.1 Dredge Areas .......................................................................................................... 17 4.2.2 Placement Areas..................................................................................................... 17 4.3 Sediment Quality ........................................................................................................... 17 4.3.1 Dredge Areas .......................................................................................................... 17 4.3.2 Placement Areas..................................................................................................... 23 4.4 Wetlands – All Areas ..................................................................................................... 26 4.5 Benthos ........................................................................................................................... 26 4.5.1 Dredge Areas .......................................................................................................... 26 iii FINAL DRAFT ENVIRONMENTAL ASSESSMENT: Wood Island Harbor and the Pool at Biddeford ________________________________________________________________________________________________________ 4.5.2 Placement Areas..................................................................................................... 27 4.6 Shellfish ........................................................................................................................... 29 4.6.1 Dredge Areas............................................................................................................. 30 4.6.2 Placement Areas ....................................................................................................... 30 4.7 Lobster ............................................................................................................................. 33 4.7.1 Dredge Areas............................................................................................................. 33 4.7.2 Placement Areas ....................................................................................................... 34 4.8 Eelgrass .......................................................................................................................... 34 4.8.1 Dredge Areas............................................................................................................. 35 4.8.2 Placement Areas ....................................................................................................... 36 4.9 Finfish Resources – All Areas ..................................................................................... 38 4.9 Other Wildlife – All Areas ............................................................................................. 40 4.10 Threatened and Endangered Species – All Areas ................................................. 42 4.10.1 Birds and Terrestrial Mammals ..................................................................... 42 4.10.1.1 Federally Listed Species .................................................................................. 43 4.10.1.2 State Listed Species ......................................................................................... 45 4.10.1.3 Migratory Birds and Birds of Conservation Concern ................................... 47 4.10.2 Fish and Marine Mammals ........................................................................... 48 4.11 Essential Fish Habitat ............................................................................................ 51 5.0 Historic and Archaeological Resources ..................................................................... 52 6.0 Recreation and Aesthetics ........................................................................................... 52 7.0 Air Quality and Noise .................................................................................................... 53 8.0 Environmental Consequences .................................................................................... 54 8.0.1 No Action Alternative ................................................................................................. 54 8.1 Water and Sediment Quality ........................................................................................ 54 8.1.1 Dredge Areas............................................................................................................. 54 8.1.2 Placement Areas ....................................................................................................... 55 8.1.2.1 Hills Beach .............................................................................................................. 56 8.1.2.2 Camp Ellis Beach Nearshore Placement area ................................................. 56 8.1.2.3 Saco Bay Disposal Site ........................................................................................ 56 8.2 Wetlands – All Areas ..................................................................................................... 57 8.3 Benthos ........................................................................................................................... 58 iv FINAL DRAFT ENVIRONMENTAL ASSESSMENT: Wood Island Harbor and the Pool at Biddeford ________________________________________________________________________________________________________ 8.3.1 Dredge Areas............................................................................................................. 58 8.3.2 Placement Areas ....................................................................................................... 58 8.4 Shellfish ........................................................................................................................... 59 8.4.1 Dredge Areas............................................................................................................. 59 8.4.2 Placement Areas ....................................................................................................... 59 8.5 Lobster ............................................................................................................................. 60 8.5.1 Dredge Areas............................................................................................................