SYLLABUS This Final Feasibility Report presents the results of investigations to provide protection to the critical habitat area of the endangered whooping crane. Justification for measures recommended in this report are based on provisions of the Endangered Species Act of 1973. The Gulf Intracoastal Waterway traverses approximately 31 miles of the critical habitat area and includes portions of the Aransas National Wildlife Refuge and the privately-owned Welder Flats area and State-owned Welder Flats Coastal Preserve located on the easterly portion of the study area. Erosion along the channel banks is occurring from a combination of causes, including waterway usage and natural processes. Various alternatives to reduce erosion through this reach and to minimize impacts from possible contaminant spills that could occur from waterway traffic were investigated. These measures included channel rerouting outside of the critical habitat, alternate routes within the critical habitat, and retention of the existing channel alignment. As a result of these investigations and through coordination with the various Federal and State resource agencies, the plan ultimately selected consists of providing 62,000 feet of bank protection for erosion control and the installation of permanent facilities for ready­ deployment of spill control measures. The recommended bank protection is in addition to that previously installed (prior to 1996) as well as that which is planned to be installed through 1997 under the Operations and Maintenance program. This report has demonstrated a Federal interest in providing erosion protection to areas within the critical habitat of the endangered whooping crane adjacent to the waterway and providing spill containment features and equipment to protect those areas from accidental hazardous spills. Total construction costs for this plan, including detail design costs, is estimated at $17,819,000, all of which will be Federal costs. Average annual maintenance cost for these plan features is estimated to be approximately $49,000. Operation, maintenance, repair, replacement, and rehabilitation will be the responsibility of the Corps of Engineers. Deployment of spill containment booms and clean-up following an accidental spill will be the responsibility of the Texas General Land Office, U.S. Coast Guard, and the U.S. Fish and Wildlife Service. Project construction is currently planned to begin in April 1998 and be completed by October 2000. Associated with the plan, but not a part of the recommendation for Congressional authorization, is the development of a long-term dredged material management plan for future maintenance activities along this reach of the waterway. The long-term dredged material management plan provides for the beneficial use of channel maintenance material to create 1,614 acres of new marsh over a 50-year period. The disposal plan will be implemented through the Operations and Maintenance program. This report contains a Final Environmental Impact Statement which considers project impacts as well as those associated with the long-term dredged material disposal plan. The requirements of Section 404(r) of Public Law 92-500, as amended, have been met. GULF INTRACOASTAL WATERWAY ARANSAS NATIONAL WILDLIFE REFUGE (SECTION 216 STUDY) FEASIBILITY REPORT TABLE OF CONTENTS SECTION PAGE INTRODUCTION 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 DESCRIPTION OF T HE AREA 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 STUDY AUTHORITY 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 3 STUDY PURPOSE AND SCOPE 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 3 STUDY PARTICIPANTS AND COORDINATION 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 5 PRIOR STUDIES AND REPORTS 0 0 0 0 0 0 0 0 0 0 0 0 0 0 - 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 6 THE STUDY PROCESS 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 6 HISTORY OF THE AREA 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 8 HISTORY OF THE WHOOPING CRANE 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 8 HISTORY OF THE ARANSAS NATIONAL WILDLIFE REFUGE 0 0 0 0 0 0 0 0 0 0 0 0 0 0 9 HISTORY OF THE GIWW 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 10 EXISTING CONDITIONS 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 13 CLIMATE 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 13 PHYSIOGRAPHY 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 13 AQUATIC RESOURCES 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 14 TERRESTRIAL RESOURCES 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 o 0 0 15 GULF PRAIRIE 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0. 0 0 0 o 16 GULF SANDS 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 16 SALTMARSH 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 o 16 WILDLIFE RESOURCES 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 o 0 0 17 CRANE USAGE OF HABITAT TYPES 0 0 0 0 0 0 0 0 0 0 0 0 0 0 o 0 0 0 0 o 0 0 0 0 0 0 0 0 0 0 0 0 0 18 THREATEN ED AND ENDANGERED SPECIES o 0 o 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 19 HISTORIC RESOURCES 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 o 0 0 • 0 0 0 o 22 HAZARDOUS AND TOXIC WASTE CONSIDERATIONS 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 o 22 POPULATION 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 • 0 0 0 • 0 0 0 0 23 ECONOMIC BASE 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 • 0 0 0 0 0 0 0 0 • 0 0 0 • 0 0 0 0 0 0 23 SOCIOECONOMIC VALUES 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 o 0 0 0 0 0 0 0 0 0 0 • 0 0 24 TABLE OF CONTENTS SECTION PAGE PROBLEM IDENTIFICATION .