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Despite increasing confidence in global climate change projections in recent years, projections of climate effects at local scales remains scarce. Location-specific risks to transportation systems imposed by changes in climate are not yet well known. However, consideration of these long-term factors are highly relevant for infrastructure components, such as rail lines, highways, bridges, and ports, that are expected to provide service for up to 100 years. To better understand climate change impacts on transportation infrastructure and to identify potential adaptation strategies, the U.S. Department of Transportation (USDOT) is conducting a comprehensive multiphase study of climate change impacts in the Central Gulf Coast region. This region was selected as the study's focal point due to its dense population and complex network of transportation infrastructure, as well as its critical economic role in the import and export of oil, gas, and other goods. The study is funded by the USDOT Center for Climate Change and Environmental Forecasting and managed by FHWA. The Gulf Coast Study has two distinct study periods: Phase 1 (2003 to 2008) examined the impacts of climate change on transportation infrastructure at a regional scale; and Phase 2 is focusing on a smaller region, enhancing regional decision makers' ability to understand potential impacts on specific critical components of infrastructure, and to start evaluating adaptation options. This report, the Task 2 report, lays the climate data foundation upon which a vulnerability assessment will be conducted in the next task. In future steps of the project, a vulnerability screen will be conducted along with an assessment of the highly critical assets identified previously under Task 1, as reported in the Task 1 final report Assessing Infrastructure for Criticality in Mobile, AL. This report explores potential changes in five primary climate variables: temperature, precipitation, streamflow, sea level rise, and storm surge in Mobile, AL, the location selected as the study area for Phase 2. To do so, Task 2 characterizes the current climate conditions in Mobile, and then uses downscaled climate projection data, as well as sea level rise and storm surge modeling, to develop plausible climate futures. The climate information discussed in this report will be used to assess how the transportation system in Mobile might be affected by climate change. Although this report does focus on Mobile, AL, the processes developed under this Task can be replicated by other transportation organizations across the country. The ultimate goal of this report is to not just identify how climate could change in Mobile, but also to develop robust methodologies, and identify existing datasets and tools, for developing these plausible climate futures. Furthermore, the work conducted under Task 2 will help inform the development of tools and resources to make these types of analyses easier for transportation agencies. To that end, the process of Task 2 is just as important as the results.

The U.S. Department of Transportation conducted a comprehensive, multi-phase study of the Central Gulf Coast region to better understand climate change impacts on transportation infrastructure and identify potential adaptation strategies. This region is home to a complex multimodal network of transportation infrastructure, and it plays a critical economic role in the import and export of oil and gas, agricultural products, and other goods. Phase 1 of this Gulf Coast Study examined the impacts of climate change on transportation infrastructure at a regional scale. Phase 2 focused on a smaller region, enhancing regional decision makers' ability to understand potential impacts on specific components of infrastructure and to evaluate adaptation options. An important goal of Phase 2 was to develop methodologies that could be used by other transportation agencies to evaluate vulnerability and adaptation measures. With that goal in mind, the project team developed transferrable methodologies and pilot tested them on the transportation system in Mobile, Alabama. This study evaluated the impacts on six transportation modes (highways, ports, airports, rails, transit, and pipelines) from projected changes in temperature and precipitation, sea level rise, and the storm surges and winds associated with more intense storms. The project resulted in findings in Mobile's transportation vulnerability, as well as approaches for using climate data in transportation vulnerability assessments, methods for evaluating vulnerability and adaptation options, and tools and resources that will assist other agencies in conducting similar work.

The U.S. Department of Transportation's Center for Climate Change and Environmental Forecasting is conducting a comprehensive, multi-phase study of climate change impacts on transportation in the Central Gulf Coast region. This study, formally known as Impacts of Climate Change and Variability on Transportation Systems and Infrastructure: Gulf Coast Study, is the first such study of its magnitude in the United States and thus represents an important benchmark in our understanding of what constitutes an effective transportation system adaptation planning effort. This report presents the findings of the first task of Phase 2 of this study-identifying critical transportation assets. While confidence in global climate change projections has been steadily increasing over recent years, investigations into the potential impacts of projected changes on a regional scale have been scarce. The exact risks that climate change poses to transportation systems are not yet well known. As many of the nation's infrastructure components, such as rail lines, highways, bridges, and ports, are expected to last for up to 100 years, it is important that their design and long-term operations consider factors that could affect their resilience and effectiveness over their life span, such as changing environmental conditions due to climate change. The Gulf Coast Study was initiated to better understand climate change impacts on transportation infrastructure and to identify potential adaptation strategies. This study area was selected as the study's focal point due to its dense population and complex network of transportation infrastructure, as well as its critical economic role in the import and export of oil, gas, and other goods. The Gulf Coast Study includes two phases: Phase 1 - The study assessed likely changes in temperature and precipitation patterns, sea level rise, and increasing severity and frequency of tropical storms. Phase 1 then explored how these changes could impact transportation systems. Phase 2 - The purpose of Phase 2 is to provide a more detailed assessment of the vulnerability of the most critical components of the transportation system to weather events and long-term changes in climate. This work is being conducted on a single metropolitan area-the Mobile, AL region -with the intention of making the processes used in the study replicable to other areas.

Facility managers, transportation planners, and elected officials are increasingly concerned about the resilience of transportation infrastructure to a range of threats, including the threats posed by climate change and extreme weather. However, the information and tools necessary to understand, evaluate, and rank vulnerabilities remains scarce. This is particularly true as it relates to specific facilities and the assets that constitute a facility; even more scarce is information and data regarding adaptation (i.e., risk mitigation) measures, their efficacy in reducing risks, and the returns on investment that might be expected if adaptation strategies are adopted. Because many assets (e.g., rail lines, bridges, and piers) are expected to provide service for 100 years or longer, consideration of medium, and long-term climate threats is essential to ensuring safe and effective transportation services at all levels of authority (i.e., federal, state, county, and municipal) and for both publicly and privately managed assets. Acknowledging the importance of establishing systematic, transferrable approaches for assessing and addressing vulnerability to climate and weather risks, the USDOT's Center for Climate Change and Environmental Forecasting commissioned a comprehensive, multiphase study of climate change impacts on transportation in the Central Gulf Coast region. This study is the first such study of its magnitude in the United States and represents an important benchmark in the understanding of what constitutes an effective transportation system adaptation effort. The Gulf Coast region was selected as the focal point due to its dense population and complex network of transportation infrastructure, as well as its critical economic role in the import and export of oil, gas, and other goods. The Gulf Coast Study includes two phases: Phase 1 - investigated potential climate change risks and impacts on coastal ports, road, air, rail, and public transit systems. The study assessed likely changes in temperature and precipitation patterns, sea level rise, and increasing severity and frequency of tropical storms. Phase 1 then explored how these changes could impact transportation systems. Phase 2 - The purpose of Phase 2 is to provide a more detailed assessment of the vulnerability of the most critical components of the transportation system to weather events and long-term changes in climate. This work is being conducted on a single metropolitan area, the Mobile, Alabama region, with the intention of making the processes used in the study replicable to other areas.

Despite increasing confidence in global climate change projections in recent years, projections of climate effects at local scales remain scarce. Location-specific risks to transportation systems imposed by changes in climate are not yet well known. However, consideration of these long-term factors is highly relevant for infrastructure components, such as rail lines, highways, bridges, and ports, that are expected to provide service for up many years. To better understand climate change impacts on transportation infrastructure and to identify potential adaptation strategies, the U.S. Department of Transportation's Center for Climate Change and Environmental Forecasting is conducting a comprehensive, multiphase study of climate change impacts on transportation in the Central Gulf Coast region. This study, formally known as Impacts of Climate Change and Variability on Transportation Systems and Infrastructure: Gulf Coast Study, is the first such study of its magnitude in the United States and represents an important benchmark in the understanding of what constitutes an effective transportation system adaptation planning effort. The Gulf Coast region was selected as the focal point due to its dense population and complex network of transportation infrastructure, as well as its critical economic role in the import and export of oil, gas, and other goods. The study is funded by the U.S. DOT Center for Climate Change and Environmental Forecasting and managed by FHWA. The U.S. Geological Survey (USGS) has provided support for much of the climate science work. The Gulf Coast Study includes two phases: Phase 1- The study assessed likely changes in temperature and precipitation patterns, sea level rise, and increasing severity and frequency of tropical storms. Phase 1 then explored how these changes could impact transportation systems. Phase 2 - The purpose of Phase 2 is to provide a more detailed assessment of the vulnerability of the most critical components of the transportation system to weather events and long-term changes in climate. This work is being conducted on a single metropolitan area-the Mobile, AL region -with the intention of making the processes used in the study replicable to other areas.

Continued growth in travel on congested urban freeway corridors exceeds the ability of agencies to provide sufficient solutions and alternatives based on traditional roadway expansion and improvement projects. Several countries are implementing managed motorway concepts to improve motorway capacity without acquiring more land and building large-scale infrastructure projects. The Federal Highway Administration, American Association of State Highway and Transportation Officials, and National Cooperative Highway Research Program sponsored a scanning study of England, Germany, the Netherlands, and Spain to examine the use of innovative geometric design practices and techniques to improve the operational performance of congested freeway facilities without compromising safety. Managed motorways are a combination of active or dynamically managed operational regimes, specific designs of infrastructure, and technology solutions. The concept uses a range of traffic management measures to actively monitor the motorway and dynamically control speeds, add capacity, and inform road users of conditions on the network with the objective to optimize traffic and safety performance. Examples include shoulder running, variable mandatory speed limits, lane control signals, and driver information using variable message signs. Managed motorways increase journey reliability and throughput of a motorway by speed management and increase capacity by shoulder running.

This manual is intended to provide a technical resource for geotechnical engineers responsible for planning and performing subsurface investigations so that project subsurface conditions can be characterized effectively and risks attributed to ground conditions can be identified and addressed. The manual is organized to reflect an emphasis on interpretation of geotechnical parameters for design and construction. It describes important considerations for planning and scoping of geotechnical investigations; means and methods for classification of soil and rock based on index property measurements; identifying and characterizing problematic soil and rock types for design and construction; guidance for interpretation of soil and rock properties from field and laboratory measurements; interpretation of geotechnical design parameters from individual measurements; identification and characterization of geotechnical hazards; and lastly, guidance for documenting and reporting results from geotechnical investigations.

This document presents information on the analysis, design, and construction of driven pile foundations for highway structures. This document updates and replaces FHWA NHI-05-042 and FHWA NHI-05-043 as the primary FHWA guidance and reference document on driven pile foundations. The manual addresses design aspects including subsurface exploration, laboratory testing, pile selection, aspects of geotechnical and structural limit states, as well as technical specifications. Construction aspects including static load tests, dynamic tests, rapid load tests, wave equation analyses, dynamic formulas and development of driving criteria, as well as pile driving equipment, pile driving accessories, and monitoring of pile installation inspection are also covered. Step by step procedures are included for most analysis procedures and design examples.

This document presents information on the analysis, design, and construction of driven pile foundations for highway structures. This document updates and replaces FHWA NHI-05-042 and FHWA NHI-05-043 as the primary FHWA guidance and reference document on driven pile foundations. The manual addresses design aspects including subsurface exploration, laboratory testing, pile selection, aspects of geotechnical and structural limit states, as well as technical specifications. Construction aspects including static load tests, dynamic tests, rapid load tests, wave equation analyses, dynamic formulas and development of driving criteria, as well as pile driving equipment, pile driving accessories, and monitoring of pile installation inspection are also covered. Step by step procedures are included for most analysis procedures and design examples.

This document presents information on the analysis, design, and construction of driven pile foundations for highway structures. This document updates and replaces FHWA NHI-05-042 and FHWA NHI-05-043 as the primary FHWA guidance and reference document on driven pile foundations. The manual addresses design aspects including subsurface exploration, laboratory testing, pile selection, aspects of geotechnical and structural limit states, as well as technical specifications. Construction aspects including static load tests, dynamic tests, rapid load tests, wave equation analyses, dynamic formulas and development of driving criteria, as well as pile driving equipment, pile driving accessories, and monitoring of pile installation inspection are also covered. Step by step procedures are included for most analysis procedures and design examples.

This course manual is intended for design and construction professionals involved with the selection, design and construction of geotechnical features for surface transportation facilities. The manual is geared towards practitioners who routinely deal with soils and foundations issues but who may have little theoretical background in soil mechanics or foundation engineering. The manual's content follows a project-oriented approach where the geotechnical aspects of a project are traced from preparation of the boring request through design computation of settlement, allowable footing pressure, etc., to the construction of approach embankments and foundations. A complete example bridge project is included.

This course manual is intended for design and construction professionals involved with the selection, design and construction of geotechnical features for surface transportation facilities. The manual is geared towards practitioners who routinely deal with soils and foundations issues but who may have little theoretical background in soil mechanics or foundation engineering. The manual's content follows a project-oriented approach where the geotechnical aspects of a project are traced from preparation of the boring request through design computation of settlement, allowable footing pressure, etc., to the construction of approach embankments and foundations. A complete example bridge project is included.

This book is FHWA's primary reference of recommended design and procurement procedures for shallow foundations. It presents state-of-the-practice guidance on the design of shallow foundation support of highway bridges. The information is intended to be practical in nature, and to especially encourage the cost-effective use of shallow foundations bearing on structural fills. To the greatest extent possible, the document coalesces the research, development and application of shallow foundation support for transportation structures over the last several decades. Detailed design examples are provided for shallow foundations in several bridge support applications according to both Service Load Design (Appendix B) and Load and Resistance Factor Design (Appendix C) methodologies. Guidance is also provided for shallow foundation applications for minor structures and buildings associated with transportation projects.

This book presents state-of-the-practice information on the design and installation of cement-grouted ground anchors and anchored systems for highway applications. The anchored systems discussed include flexible anchored walls, slopes supported using ground anchors, landslide stabilization systems, and structures that incorporate tiedown anchors. This book draws extensively in describing issues such as subsurface investigation and laboratory testing, basic anchoring principles, ground anchor load testing, and inspection of construction materials and methods used for anchored systems. This book provides detailed information on design analyses for ground anchored systems. Topics discussed include selection of design earth pressures, ground anchor design, design of corrosion protection system for ground anchors, design of wall components to resist lateral and vertical loads, evaluation of overall anchored system stability, and seismic design of anchored systems. Also included in this book are two detailed design examples and technical specifications for ground anchors and for anchored walls.

This manual provides state-of-the-practice methods and techniques to assist the highway engineer in the planning, design, and construction monitoring of dynamic compaction to improve the load supporting capacity of weak foundation soils. Guidelines are presented for: completing a preliminary evaluation to determine if dynamic compaction is appropriate for the site and subsurface conditions detailed design for site improvement preparation of a specification construction monitoring Two case histories of actual projects are presented to demonstrate the use of the guidelines.

ntroduction to Highway Hydraulics provides an introduction to highway hydraulics. Hydrologic techniques presented concentrate on methods suitable to small areas, since many components of highway drainage (culverts, storm drains, ditches, etc) service primarily small areas. A brief review of fundamental hydraulic concepts is provided, including continuity, energy, momentum, hydrostatics, weir flow and orifice flow. The book then presents open channel flow principles and design applications, followed by a parallel discussion of closed conduit principles and design applications. Open channel applications include discussion of stable channel design and pavement drainage. Closed conduit applications include culvert and storm drain design. Examples are provided to help illustrate important concepts. An overview of energy dissipators is provided and the document concludes with a brief discussion of construction, maintenance and economic issues. As the title suggests, Introduction to Highway Hydraulics provides only an introduction to the design of highway drainage facilities and should be particularly useful for designers and engineers without extensive drainage training or experience.