Integrated Detailed Project Report & Environmental Assessment E. Branch Au Gres River Sea Lamprey Traps Iosco County, Michigan Section 506 Great Lakes Fishery & Ecosystem Restoration US Army Corps of Engineers ® Detroit District BUILDING STRONG ® April 2016 This Page Intentionally Left Blank EXECUTIVE SUMMARY The invasive sea lamprey (Petromyzon marinus) has colonized many rivers in the Great Lakes Region including the East Branch Au Gres River. The purpose of this integrated DPR and EA is to identify potential alternatives for improving sea lamprey population control in the East Branch Au Gres River under the authority of Section 506 Great Lakes Fishery and Ecosystem Restoration. The main objectives of the study were: 1) Capture and remove more adult sea lamprey than the current average to further limit spawning; 2) Reduce the population of spawning-phase sea lamprey in the East Branch Au Gres River to reduce damage to the Lake Huron fishery; 3) Improve integrated sea lamprey control to potentially reduce or eliminate use of lampricide treatments. The USACE, in coordination with the Great Lake Fishery Commission (GLFC), determined the best location for this project to be at an existing Michigan Department of Natural Resources (MDNR) sea lamprey barrier in Iosco County, MI. Five alternatives were developed for sea lamprey control at this site: 1) No Action – Use of temporary traps and TFM (chemical lampricide) 2) Alternative 2 – Use of TFM only 3) Alternative 3 – Install Permanent Attractant Water Trap (AWT) System at the west bank of the barrier 4) Alternative 4 – Install Permanent Attractant Water Trap (AWT) System at the east bank of the barrier 5) Alternative 5 – Install Permanent Attractant Water Trap (AWT) System across the entire face of the barrier. The alternatives analysis demonstrated Alternative 2 is not acceptable since it does not address population control of adult, spawning-phase adults and it would increase reliance on lampricides. Therefore it was dropped from detailed analysis. Alternatives 1, 3, 4, and 5 were identified as cost effective and were carried forward into the incremental cost analysis (ICA). The results of the ICA showed the incremental cost per incremental sea lamprey removed is lower for Alternative 3 therefore making it the recommended (NER) alternative. Alternative 3 was found to be consistent with the goals and objectives of the study, is cost-effective and reasonably maximizes ecosystem benefits. It has acceptable levels of risk and uncertainty. Alternative 3 is an acceptable and complete alternative and is the recommended alternative. Using a permanent attractant water trap under Alternative 3 would increase trapping efficiency from approximately 20% (temporary trap) to 58% (permanent trap). Alternative 3 results in a net increase of 1,733 sea lamprey removed annually. The fully funded total project cost for Alternative 3 is $1,064,000 (Table 9 pg 45 derived from the cost engineering appendix). i E. Branch Au Gres River Sea Lamprey Traps, Isoco County, Michigan Integrated Detailed Project Report & Environmental Assessment Table of Contents * NEPA Information found in these Chapters, Sections & Appendices Executive Summary ........................................................................................................................................................ i CHAPTER 1 – *INTRODUCTION ...................................................................................................................................... 1 1.1 – REPORT ORGANIZATION ......................................................................................................................................... 1 1.2 – STUDY AUTHORITY ................................................................................................................................................. 1 1.3 – *STUDY PURPOSE, NEED & SCOPE ........................................................................................................................... 3 1.4 – *STUDY LOCATION ................................................................................................................................................ 6 1.5 – *PERTINENT RECENT, PRESENT AND FUTURE REPORTS, STUDIES & PROJECTS ................................................................... 8 CHAPTER 2 – *INVENTORY AND FORCASTING ............................................................................................................ 10 2.1 – OVERVIEW OF THE PLAN FORMULATION PROCESS ..................................................................................................... 10 2.2 – *EXISTING CONDITIONS ........................................................................................................................................ 10 2.3 – HABITAT ASSESSMENT METHODOLOGY ................................................................................................................... 10 2.4 – *FUTURE WITHOUT PROJECT CONDITIONS ............................................................................................................... 11 2.5 – PROBLEMS AND OPPORTUNITIES ............................................................................................................................ 11 2.6 – PLANNING GOALS & OBJECTIVES ............................................................................................................................ 12 2.7 – PLANNING CONSTRAINTS ...................................................................................................................................... 15 CHAPTER 3 – *PLAN FORMULATION, EVALUATION AND SELECTION OF RECOMMENDED PLAN ............................... 16 3.1 – *MEASURE IDENTIFICATION .................................................................................................................................. 16 3.2 – MEASURE BENEFITS & COSTS ................................................................................................................................ 17 3.3 – *ALTERNATIVE PLAN GENERATION & ASSUMPTIONS .................................................................................................. 20 3.4 – ACCEPTABILITY, COMPLETENESS, EFFECTIVENESS AND EFFICIENCY ................................................................................. 24 3.5 – EVALUATING ECOSYSTEM BENEFITS ......................................................................................................................... 26 3.6 – COMPARING FINAL ARRAY OF ALTERNATIVE PLANS .................................................................................................... 29 3.7 – SELECTION OF THE RECOMMENDED ALTERNATIVE ...................................................................................................... 40 CHAPTER 4 – *DESCRIPTION OF THE RECOMMENDED ALTERNATIVE ........................................................................ 42 4.1 – *PLAN COMPONENTS & CONSTRUCTION CONSIDERATIONS ......................................................................................... 42 4.2 – *REAL ESTATE CONSIDERATIONS ............................................................................................................................ 43 4.3 – VIEWS OF PROJECT PARTNER(S) ............................................................................................................................. 44 4.4 – COST SHARING AND SPONSOR RESPONSIBILITIES ....................................................................................................... 44 4.5 – SCHEDULE .......................................................................................................................................................... 45 4.6 – PLANS & SPECIFICATIONS ...................................................................................................................................... 45 4.7 – *OPERATION & MAINTENANCE (O&M) CONSIDERATIONS ......................................................................................... 45 4.8 – *POST-CONSTRUCTION MONITORING ..................................................................................................................... 45 CHAPTER 5 – *EXISTING ENVIRONMENT AND ENVIRONMENTAL ASSESSMENT (EA) ................................................. 47 5.1 – *EA ORGANIZATION AND PRELIMINARY IMPACT SCOPING ........................................................................................... 47 5.2 – *PHYSICAL SETTING AND LAND USE ........................................................................................................................ 50 5.3 – *COASTAL ZONE MANAGEMENT, FLOODPLAINS AND HYDROLOGY ................................................................................ 52 5.4 – *HAZARDOUS, TOXIC, AND RADIOACTIVE WASTE (HTRW) ANALYSIS ........................................................................... 54 5.5 – *WATER AND SEDIMENT QUALITY .......................................................................................................................... 55 5.6 – *PRIME FARMLAND AND WETLANDS ...................................................................................................................... 57 5.7 – *GROUNDWATER AND DRINKING WATER SUPPLY...................................................................................................... 59 5.8 – *VEGETATION, WILDLIFE HABITAT AND WILDLIFE ...................................................................................................... 59 5.9 – *AQUATIC RESOURCES ........................................................................................................................................