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Recent Developments Archive

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Traffic Signal Systems Subject of Transportation Research Record

Nine research papers concerning the optimization of traffic signals are addressed in the Transportation Research Board’s Transportation Research Record journal, Volume 2619. The journal addresses adaptive coordination based on connected vehicles, evaluations of transit priority signaling, trends in transit bus dwell times, and an assessment of signal timing plans through seasonal variations. The journal also includes papers on safety and cybersecurity concerns. For more information, link to the journal. (9-14-17)


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Demand Forecasting, Pricing Addressed in Transportation Research Record

Twenty two research papers concerning demand forecasting and roadway pricing are addressed in the Transportation Research Record journals, Volume Nos. 2669 and 2670. The journals address models of travel mode and departure time choices, pricing and reliability enhancements for activity-based travel mode, and equity effects of congestion charges. The journals also address the use of congestion-priced road user charges to restore mobility and fund highways, evaluation of acceptable toll rates in road concessions, and methods to estimate time-dependent origin-destination demand in congested networks. For more information, link to the demand forecasting and finance and pricing journal issues. (8-21-17) 

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FHWA Issues 2017 Carbon Monoxide Categorical Hot-Spot Finding

The Federal Highway Administration has issued a revised carbon monoxide categorical hot-spot finding for 2017. The finding, which updates and supersedes a 2014 version, allows projects that fall within the acceptable ranges to reference the finding in place of doing an independent carbon monoxide hot-spot analysis as part of a project-level conformity determination in carbon monoxide maintenance areas. The FHWA, working with the Environmental Protection Agency, modeled a large intersection operating at capacity using the 2014 Motor Vehicle Emissions Simulator (MOVES2014a) and the CAL3QHC model to develop emission rates and acceptable ranges for modeled parameters. For more information, link to the memorandum and finding. (7-18-17) 

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Group Recommends Use of Volkswagen Settlement Funds for Clean Transportation

The use of funds from the Volkswagen emissions cheating settlement is addressed in a new report issued by the U.S. PIRG Education Fund. The settlement resulted in $2.9 billion in environmental mitigation trust (EMT) funds and $2 billion for a Zero Emission Vehicle Fund. U.S. PIRG makes the case for states to use their settlement money to adopt electric vehicles (EVs) to reduce greenhouse gas emissions and increase economic activity. The report provides a review of the existing EV charging infrastructure and potential energy and cost savings. It indicates that if $435 million in EMT funds are used, states could supply between 4,350 and 8,700 additional charging stations. The report also recommends that states invest in electrifying bus fleets, which account for the largest percentage of transportation trips and passenger miles. For more information, link to the report. (7-6-17) 

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AASHTO Practitioner’s Handbook Outlines Air Quality Issues in the NEPA Process

A Practitioner’s Handbook on air quality issues for transportation projects during the National Environmental Policy Act review process has been issued by the Center for Environmental Excellence by AASHTO. The handbook summarizes key requirements under NEPA and the Clean Air Act and provides advice for documenting compliance.  It also offers practical tips on topics including transportation conformity requirements, conducting hot-spot analyses and making project-level conformity determinations, considering mobile-source air toxics emissions, and documenting analyses and determinations in the NEPA process. For more information, including the handbook, related webinar, and webinar presentation, link here

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FHWA Offers Approach for Quantitative Mobile Source Air Toxics Analysis

An approach for conducting a quantitative mobile source air toxics (MSAT) analysis using the EPA’s MOVES2014a software on a hypothetical road widening project has been released by the Federal Highway Administration. The analysis considers how the project would change roadway volumes and impact congestion. It compares emissions between several alternatives and timeframes and for different volumes of truck traffic. The analysis is an update to a previous analysis done in 2006, incorporating more stringent Tier 2 and Tier 3 vehicle emissions standards, as well as the latest data on vehicle emissions characteristics. For more information, link to the analysis. (5-15-17)

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FHWA Newsletter Highlights Air Quality and Sustainability News

The Federal Highway Administration has published the February/March 2017 newsletter highlighting air quality and sustainability news. The newsletter includes information concerning the Executive Order on energy independence and economic growth, Q&A on emergency relief program and resilience and the Atlanta peer exchange on climate resilience. The newsletter also includes information regarding new resilience elements in the transportation planning rule and project development assessment of climate change and lists upcoming meetings, conferences, workshops, and training opportunities. For more information, link to the newsletter. (4-17-17) 

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EPA to Hold Teleconference on Air Quality Regulatory Actions

The Environmental Protection Agency's Office of Air and Radiation has scheduled a public teleconference to obtain feedback on air- and radiation-related regulatory actions. The teleconference will be held on April 24, from 11 a.m. to 2  p.m. EDT. The dial-in number is (800) 305-3182, conference ID# 8535873.  Callers may nominate themselves to speak by hitting *1 to be added to a queue. Speakers will be asked to deliver 3 minutes of remarks and will be called on a first come, first served basis. The teleconference will be transcribed and will be added to the docket. Individuals that do not have the opportunity to speak on the call may submit input to the EPA-wide docket (docket number: EPA-HQ-OA-2017-0190).  (4-17-17)

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Smart Growth America Highlights Complete Streets Success Under FAST Act

Successful implementation of complete streets provisions under the Fixing America’s Surface Transportation (FAST) Act is addressed in a report from Smart Growth America. Under the provisions, National Highway System road designs are required to incorporate access for all modes of transportation and local governments are permitted to use their own design guide to creating complete streets projects. Examples of success include the development of projects along I-40 in Oklahoma City to expand bikesharing and in Atlanta where the city is devoting $109 million to complete streets improvements over the next five years. An emphasis on project planning, design and implementation is what has made the complete streets approach so fruitful. For more information, link to the announcement. (4-6-17) 

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Transportation Conformity Guide for States, Local Areas Released

The Federal Highway Administration has released a guide for state and local officials addressing determinations of whether transportation improvements conform to the air quality objectives in state implementation plans. The guide describes a conformity determination and addresses the responsibility for making those determinations. The guide includes the elements of a conformity determination, such as interagency consultation and regional emissions analysis, and highlights options for metropolitan planning organizations to reduce emissions. The guide also addresses project-level conformity and hot-spot analysis required for federal highway and transit projects. For more information, link to the guide. (February 2017)

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WRI Report Describes Low Emission Zone/Congestion Charging Scheme

The World Resources Institute, in coordination with the Beijing Transport Institute, has released a report regarding the low emission zone and congestion charging (LEZ/CC) scheme. The report focuses on surcharges within congested road areas and the designation of emission control areas to reduce vehicle pollutants in London, Singapore and Stockholm to assist similar efforts in China. The report includes city history of transportation policies, stakeholder engagement efforts and congestion pricing system performance and its effects on traffic within each city. The report also identifies best practices and indicates that forms of legal safeguards from national government, strong policy objectives and equity and transparency are key to successful implementation of the LEZ/CC scheme. For more information, link to the report. (3-28-17)


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Economic Potential of Low-Carbon Natural Gas Analyzed in New Report

The long-term economic potential of low-carbon natural gas (LCNG) within the transportation sector is explored in a report by the Joint Institute for Strategic Energy Analysis. The report addresses the use of LCNG, which includes methane from biomass and fossil gas mixed with hydrogen, in light, medium and heavy-duty vehicles. The report includes data concerning woody and herbaceous feedstocks to produce biogas to determine total resource potential for LCNG production and an analysis of projected transportation fuel demand. The report also analyzes emissions regarding a vehicle’s cumulative emissions on a per-mile-traveled basis and includes calculations for each LCNG pathway’s total cost. For more information, link to the report. (3-18-17)

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EPA to Revisit Greenhouse Gas Standards for Light-Duty Vehicles

The U.S. Department of Transportation and Environmental Protection Agency have announced that the EPA will reconsider a final determination regarding the midterm evaluation of greenhouse gas standards for light duty vehicles from model years 2022-2025. The previous determination found that automakers were well positioned to meet the standards at lower costs than previously estimated. The reconsideration will be coordinated with the parallel process to be undertaken by the DOT’s National Highway Transportation Administration regarding corporate average fuel economy standards for cars and light trucks for the same model years. EPA intends to make a new final determination regarding the appropriateness of the greenhouse gas standards by April 1, 2018. For more information, link to the EPA midterm evaluation website and to the notice. (3-15-17)

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Travel Demand Forecasting Covered in Transportation Research Record

Fifteen research papers on travel demand forecasting are included in the Transportation Research Board’s Transportation Research Record. Papers include transportation planning though peer-to-peer modeling, microsimulation of demand and supply of autonomous mobility on demand, and the use of predicted bicycle and pedestrian route choice to enhance mode choice models. It also includes papers on assumptions inherent in assessing traffic forecast accuracy, evaluation of transport user benefits and measurement of self-selection effects to understand travel behavior impacts. For more information, link to the report. (3-5-17) 

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Guidance on Alternative Fuel Corridor Signs Issued by FHWA

The Federal Highway Administration has issued guidance concerning use of signs for designated alternative fuel corridors. The guidance, which notes that such signs are not mandatory, specifies that all signs that are developed for such corridors should use simplified message content with reasonable sign size, while minimizing driver distraction through limited use of the signing and proper placement. The guidance also specifies that general service signage is limited to compressed natural gas, liquefied natural gas, electric vehicles, hydrogen and liquefied petroleum gas usage. The guidance includes instructions for signs installed on freeways, expressways and conventional roads and provides detailed illustrations of how signs should be presented. Use of such signs is not mandatory. For more information, link to the guidance. (12-21-17)  

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FHWA Newsletter Highlights Air Quality and Climate Change News

The Federal Highway Administration (FHWA) has published the December 2016/January 2017 newsletter highlighting air quality and climate change news. The newsletter includes information concerning the Environmental Protection Agency’s final rule on guidelines for air quality models, the proposed 2015 Ozone Standard Implementation Rule and updates to the Motor Vehicle Emission Simulator 2014a. The newsletter also provides information on the 6th Transportation Research Board annual meeting and lists upcoming meetings, conferences, workshops, and training opportunities. For more information, link to the newsletter. (2-2-17)

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FHWA Updates CMAQ Toolkit for Diesel Technologies

The Federal Highway Administration has announced an update to the Congestion Mitigation and Air Quality (CMAQ) Emission Calculator Toolkit. The update adds a module for advanced diesel truck/engine technologies, which includes an on-road activity calculator, an on-road diesel repower or replacement calculator and an on-road diesel retrofits calculator. The tool also provides users with Motor Vehicle Emissions Simulator documentation with national-scale run parameters to support calculation of on-road diesel retrofit and on-road repower/replacement. For more information, link to the toolkit. (1-6-17)

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Featured Case Study

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    Georgia DOT supports a range of efforts such as the Georgia Commute Options Program to help reduce auto-related air emissions.

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