Recent technical studies and public opinion have reached a consensus: traffic congestion in urban areas is worsening. Compounding this problem is the impact that cities and metropolitan regions are having on future climate change projections. Currently, a little over 50 percent of the world’s population is classified as living in urban areas; urban communities produce approximately 75 percent of the world’s GDP and greenhouse gas emissions. The proportion of urban inhabitants is predicted to rise to 66% by the middle of this century – representing an additional 2.5 billion people. As well, the US transportation sector—which includes cars, trucks, planes, trains, ships, and freight—produces nearly thirty percent of all US global warming emissions. In an effort to stay within the safety threshold of a 2°C increase in average temperature, the transportation sector will need to be decarbonized. By addressing the carbon emissions in cities with a focus upon transportation policies and price-setting on carbon, we stand a sound prospect of positively influencing progress on virtually all the other goals (i.e., reduction in emission by 70% by 2050 as compared to 2010 levels).
While federal agencies and national politicians are still debating the authenticity of climate change, local city officials have not been allowed such a luxury. Cities are on the front lines of the environmental crisis that has accompanied climate change and global warming. Finding the solutions to coastal flooding, rising temperatures, and the heat island effect (where urban areas tend to be hotter than nearby rural areas) as well as pollution and carbon emissions will begin at the local level. Mayors around the world are pushing for green development— as energy over the next 15 years is expected to account for 28 percent of global infrastructure investment. There is a need for concrete action for energy efficiency and cost savings.
Current approaches to improving transportation systems and policies involve building more roads, urban mass transit systems, and better planning of land use. However, depending upon a given region’s geography and existing infrastructure patterns, construction of new transportation sources may prove costly. In this regard, planners have determined that current approaches, such as adding highways, transit lines, and vehicles, bike lanes, or sidewalks, represents only part of the solution. Transportation policies should pay more attention to improving the effectiveness of existing systems and managing the demand for travel.
In an effort to achieve the global environmental goals of decarbonization, cities should consider how an economically efficient local transportation policy would involve carbon emissions taxed in relation to vehicle miles traveled (VMT) or mileage fee programs in general.
In principle, a tax on vehicle miles traveled (VMT) is an effective deterrent to use motor vehicles. An example of a successful for VMT programs can be seen in the State of Oregon, the first state to implement a mileage fee program. The program allows volunteer drivers to pay or be reimbursed for the difference between the fuel taxes they pay and the road taxes they owe. It further requires that drivers pay $.015 cents for each mile they drive as opposed to the $.30 cent gas tax.
Previously, road funding revenue was derived from a tax on gas fuel. The return from this revenue source is now being diminished because of growth in the use of fuel-efficient and electric vehicles. Drivers of fuel-efficient and electric cars pay little to no gas tax; that causes a decrease in the amount available for highway funding. In other words, people are driving the same level, if not more, but the currently generated revenue needed to fix infrastructure, roads, and invest in other resources, is declining.
Implementing a mileage fee program for congested roads is another way public officials can raise the efficiency of routes by charging the people who actually use them. At present, the majority of transportation issues in urban areas is caused by congestion that stems from the commuter use of the same streets during rush hours. To alleviate overcrowding, one mechanism is to charge a flat rate toll for road use. Another approach would be to institute a variable roadway pricing system. This would be based upon charging a higher fee on congested roads at times of congestion, and less when demand falls off.
While it is vital to implement a mileage fee program as a form of carbon pricing, it is to do so with the understanding that it can only be the start. To achieve a substantial reduction in GHG emissions as well as decarbonizing the transportation sector, subsidies both to clean technologies and to R&D of clean technologies as well as efficient, targeted regulations will also be essential.
In summary, it is recommended that public officials and city planners, engaged the public in decarbonization efforts by forging a multi-pronged (subsidies/incentives, regulations, specific locations, etc.) plan that would incorporate key pilot projects, measurement of results, and achievement of benchmarks. With that data in hand, city officials will be able to justify future programs in decarbonization.
A study sponsored by the Federal Highway Administration and conducted by Puget Sound Regional Council, reviewed how commuters would change their travel behaviors in response to variable charges for road use. Results from the study showed there was no single response that participants used to alter their commute in order to save money. Nevertheless, one finding was explicit: financial incentives influenced commuter choices. Examination of the data revealed essential deviations in household commuting patterns that could dramatically reduce congestion through the implementation of variable tolling within a regional road network. When participants were faced with a financial incentive to avoid routes with high tolls, they did so in several different ways. Participants choose to: take fewer and shorter vehicle trips; use alternate routes and times of travel, or combined multiple trips together to reduce vehicle use altogether. Overall, participants would change their commute due to financial reasons and incentives. Even so, once the study had concluded, some participants reported that the changes made in the study had become a new normal for their typical commute. The reasons cited for the continual evolution was the perceived additional benefits from shorter commutes, smoother commutes, and/or extra leisure time on public transportation since their focus could be elsewhere.