Environmental Assessment Finding of No Significant Impact, and Section 404(b)(1) Evaluation for Maintenance Dredging DRAFT Saco River Saco & Biddeford, Maine US ARMY CORPS OF ENGINEERS New England District March 2016 Draft Environmental Assessment: Saco River FNP DRAFT ENVIRONMENTAL ASSESSMENT FINDING OF NO SIGNIFICANT IMPACT Section 404(b)(1) Evaluation Saco River Saco & Biddeford, Maine FEDERAL NAVIGATION PROJECT MAINTENANCE DREDGING March 2016 New England District U.S. Army Corps of Engineers 696 Virginia Rd Concord, Massachusetts 01742-2751 Table of Contents 1.0 INTRODUCTION ........................................................................................... 1 2.0 PROJECT HISTORY, NEED, AND AUTHORITY .......................................... 1 3.0 PROPOSED PROJECT DESCRIPTION ....................................................... 3 4.0 ALTERNATIVES ............................................................................................ 6 4.1 No Action Alternative ..................................................................................... 6 4.2 Maintaining Channel at Authorized Dimensions............................................. 6 4.3 Alternative Dredging Methods ........................................................................ 6 4.3.1 Hydraulic Cutterhead Dredge....................................................................... 7 4.3.2 Hopper Dredge ........................................................................................... 7 4.3.3 Mechanical Dredge ..................................................................................... 7 4.4 Alternative Placement Sites ........................................................................... 8 4.4.1 Beach Placement ........................................................................................ 8 4.4.2 Nearshore Placement ................................................................................. 8 4.4.3 Upland Placement ........................................................................................ 8 4.4.4 In-River Placement ..................................................................................... 9 4.4.5 Open Water Placement ............................................................................... 9 5.0 ENVIRONMENTAL SETTING ...................................................................... 11 5.1 General Description and Land Use Characteristics ..................................... 11 5.2 Physical and Chemical Environment ............................................................ 11 5.2.1 Water Quality ............................................................................................. 11 5.2.2 Sediment Analyses .................................................................................... 12 5.2.2.1 Dredge Areas ......................................................................................... 12 5.2.2.2 In- River Placement Area ....................................................................... 12 5.2.2.3 Camp Ellis Beach .................................................................................... 13 5.2.2.4 Nearshore Adjacent to Camp Ellis Beach .............................................. 14 5.3 Biological Resources ................................................................................... 14 5.3.1 Shellfish – all areas .................................................................................... 14 5.3.2 Benthic Communities ................................................................................ 15 5.3.2.1 Dredge Areas ......................................................................................... 15 5.3.2.2 Camp Ellis Beach and Adjacent Nearshore Area ................................... 16 5.3.2.3 In-River Placement ................................................................................ 16 5.3.3 Fisheries Resources- all areas .................................................................. 17 5.3.4 Eelgrass .................................................................................................... 20 5.3.5 Wildlife Resources .................................................................................... 20 5.3.5.1 General Wildlife Species ........................................................................ 20 5.3.5.2 Birds ...................................................................................................... 20 5.4 Essential Fish Habitat ................................................................................... 22 5.5 Threatened and Endangered Species ......................................................... 22 5.5.1 Birds and Mammals ................................................................................ 22 5.5.1.1 Piping Plover .......................................................................................... 22 i Draft Environmental Assessment: Saco River FNP 5.5.1.2 Red Knot ................................................................................................ 23 5.5.1.3 Roseate Tern .......................................................................................... 24 5.5.1.4 Northern Long Eared Bat ........................................................................ 24 5.5.2 Fish ........................................................................................................... 25 5.5.2.1 Shortnose Sturgeon ............................................................................... 25 5.5.2.2 Atlantic Sturgeon ..................................................................................... 26 5.5.2.3 Atlantic Salmon ....................................................................................... 28 5.6 Land Use, Recreation, and Public Interest Areas ........................................ 28 5.7 Socioeconomics ............................................................................................ 28 5.8 Historic and Archeological Resources ......................................................... 30 5.8.1 Pre-Contact (Native American) Archaeology ........................................... 30 5.8.2 History and Historical Archaeology .......................................................... 30 5.9 Air Quality .................................................................................................... 32 6.0 ENVIRONMENTAL CONSEQUENCES ....................................................... 32 6.0.1 No Action Alternative ................................................................................ 32 6.0.2 Preferred Alternatives ............................................................................... 33 6.1 Physical and Chemical Impacts ................................................................... 33 6.1.1 Dredge Areas ............................................................................................ 33 6.1.2 Placement Sites ........................................................................................ 34 6.1.2.1 Beach Placement ................................................................................... 34 6.1.2.2 In-River Placement .............................................................................. 35 6.2 Biological Impacts ........................................................................................ 35 6.2.1 No Action Alternative ................................................................................ 35 6.2.2 Dredge Areas ............................................................................................ 35 6.2.3 Placement Areas ....................................................................................... 38 6.2.3.1 Beach and Nearshore Placement .......................................................... 38 6.2.3.2 In-River Placement ................................................................................ 40 6.3 Essential Fish Assessment .......................................................................... 41 6.3.1 No Action Alternative ............................................................................... 41 6.3.2 Proposed Alternative ............................................................................... 42 6.4 Threatened and Endangered Species ......................................................... 42 6.4.1 Birds and Mammals .................................................................................. 42 6.4.2 Fish ........................................................................................................... 43 6.5 Historic and Archeological Resources ......................................................... 45 6.5.1 Pre-Contact (Native American) Archaeology ............................................. 45 6.5.1.1 Saco River and Camp Ellis Beach Areas ............................................... 45 6.5.1.2 History and Historical Archaeology ........................................................ 45 6.6 Socioeconomic Environment........................................................................ 47 6.6.1 No Action Alternative ................................................................................ 47 6.6.2 Dredge and Placement Areas ................................................................... 47 7.0 AIR QUALITY STATEMENT OF CONFORMITY ......................................... 47 7.1 General Conformity ...................................................................................... 48 8.0 ENVIRONMENTAL JUSTICE AND IMPACTS ON CHILDREN .................... 48 9.0 CUMULATIVE IMPACTS ............................................................................