This slide deck presents the findings from a report developed by the Federal Highway Administration to examine the potential for synergistic emissions benefits for groups of projects funded by the Congestion Mitigation and Air Quality Improvement program, known as the CMAQ program.
The work was conducted under contract to FHWA by Cambridge Systematics in late 2019 and early 2020.
The report considers the extent to which multiple projects funded through the CMAQ program might have synergistic effects—i.e., the benefits of a whole set of state or regionally funded projects being greater than the sum of the benefits of individual projects.
The report is intended to provide information to help inform policy and investment decisions by States and by Metropolitan Planning Organizations, or MPOs.
The report provides information on opportunities and challenges when combining projects into synergistic groups, such as issues related to feasibility, geographic distribution, and addressing multiple pollutants.
The report may also support potential programmatic assessments covering groups of CMAQ projects, which is a possible approach to CMAQ project evaluation described in FHWA's 2013 Interim Program Guidance on the CMAQ program.
Finally, the report lays a framework for future quantitative testing of suites of CMAQ projects for combined benefits.
While the report makes reference to sample projects, it makes no claim regarding the eligibility of any of these project examples. States and MPOs should consult with their FHWA Division office with any questions regarding project eligibility.
Before we talk more about the project, a little background on the CMAQ program.
The CMAQ program is a Federal-aid highway funding program that was first established in the Intermodal Surface Transportation Efficiency Act of 1991, or ISTEA.
The program was established to help fund transportation projects or programs that contribute to the attainment or maintenance of the National Ambient Air Quality Standards.
To be eligible for CMAQ funds, a transportation project must have demonstrated emission reductions. States are required to report estimates of CMAQ project emission reductions to FHWA on an annual basis.
The program has been reauthorized continuously since it was first established.
In the past five years annual funding for the program has averaged just under $2.5 billion.
Since 1992, the program has provided more than $38 billion to over 40,000 transportation emissions-reducing projects throughout the U.S.
Funding is distributed to States, who in many cases provide a portion of that funding to MPOs to allocate to projects within their region.
This is an outline of the contents of the report.
Like all good reports, this report on CMAQ scenario testing starts with an executive summary and then an introduction to the project.
Section 2 addresses benefits, challenges, and solutions for leveraging synergies among CMAQ projects.
Section 3 provides a summary of each type of CMAQ project identified in FHWA's Interim Guidance on the CMAQ Program. This summary identifies which types of pollutants the projects address, as well as potential synergies with projects of the same or different types.
Section 4 provides nine sample groupings of projects into synergistic scenarios. These groupings are designed around themes such as reducing traffic congestion in key corridors, or reducing emissions of ozone precursors. It then presents menus of sample projects for each of the nine groupings. Menus are presented for both metropolitan and statewide levels of application.
Section 5 draws conclusions and suggestions for further work.
Appendices include a literature review of resource documents and studies related to the CMAQ program to look for information related to synergies; a look at real-world project examples in North Carolina; and a list of references.
This figure shows the project team's approach to this project.
First, they [we] determined a set of categories used to classify CMAQ projects by type. The 17 project types outlined in FHWA's 2013 Interim Program Guidance are used.
Second, they [we] reviewed existing resources for information on synergies. Sources included FHWA materials, evaluation reports on the CMAQ program, and other related reports.
Third, they [we] described potential synergies among project types based on what we know about projects and how they might interact.
Fourth, they [we] created sample scenarios of CMAQ types that might have synergistic effects.
Finally, they [we] created sample menus of projects for each scenario.
These are the project type categories the project team considered. Some are focused on clean vehicle and fuel technology, while others are focused on demand reduction or mode shift, and others are focused on efficient traffic flow.
(Two project types from the interim guidance – Transportation Control Measures and innovative projects – are not listed separately because they can encompass a very wide range of projects.)
A review of existing resources related to the CMAQ program, which is detailed in Appendix A of the report, found little information on potential synergies.
A few synergies were hypothesized in resource documents.
However, most of the evaluation methods currently used in practice are focused on looking at project benefits individually rather than in combination.
The project team looked for examples of MPOs or States that explicitly considered synergies when programming projects but found very little. In one MPO example, a single evaluation was conducted for all phases of a multi-phase project, which is one of the types of synergies we are considering.
These are some examples of cases in which we might observe synergistic benefits.
As one example, public education programs might increase the benefits of other projects such as public transit or pedestrian and bicycle improvements by providing information about how to use those improvements.
Synergies may be geographic in nature, for example, improving a corridor or network, as shown in the example of bicycle projects that contribute to a connected network.
There may also be synergies related to scope and scale, such as leveraging economies of scale in purchasing or procurement for clean vehicle technologies.
There may be functional synergies, for example, combining mode shift with clean technology to ensure that increased transit ridership or rail freight use reduces emissions as much as possible.
States and MPOs face a number of challenges in leveraging potential synergies among CMAQ projects.
CMAQ funds may support a very diverse set of project types. Some project types are clearly related, whereas others are very different and are unlikely to have synergies with each other. Information is needed to better understand potential synergies.
Just because two projects are potentially synergistic (based on their typology) does not assure that there will be synergies. Issues of reasonableness need to be considered, as well as the feasibility of combining projects into an evaluation.
Geographic distribution of funding is often an important state or regional consideration, but consideration of geographic distribution may sometimes conflict with the ability to fund projects that are synergistic due to their proximity.
Different types of CMAQ projects may have different effects on different pollutants. Considering synergies among project types can help to leverage greater reductions in pollutants that are of local air quality concern.
Contextual factors such as metropolitan area size, population density, the balance of population in urban versus rural areas, can also have important implications for which types of CMAQ projects may be most beneficial or have the greatest synergies.
Overall there is no single formula or recipe for achieving synergies – local context needs to be considered.
This figure is a matrix illustrating potential synergies between project types. A check mark in the row for a project type indicates a relationship (and therefore a potential synergy) between that project type and the corresponding project type indicated in the column heading.
For example, the emissions benefits of freight/intermodal or transit improvement projects may be greater if diesel retrofit or advanced technologies are deployed to reduce emissions from these vehicles, in addition to any mode-shifting effects of these projects.
A check in the yellow outlined boxes in the middle means the project may have synergies with other projects of the same type – such as network connectivity effects when multiple bicycle or transit projects are implemented.
The report describes the reasons for these potential synergies in more detail.
The project team developed nine sample scenarios. This is a screen shot of excerpts of table 17 of the report, which evaluates each of these scenarios.
The scenarios are oriented around common State and MPO goals, and are formed around the following concepts:
For each scenario, the project identified which types of CMAQ projects would most likely be helpful; the potential synergistic benefits; examples of these projects; the extent to which the scenario addresses multiple pollutants; and the area types for which the projects and scenarios might be most suitable.
This table shows all nine sample scenarios and the CMAQ project types that may support each scenario. These scenarios were used as the basis for developing sample menus of projects that are likely to have synergies.
There are four scenarios with a focus on similar emission reducing mechanisms. The first scenario, to expand commute options, and the second scenario to increase active transportation, mainly include demand reduction projects that can support each other.
The third scenario, to provide clean public transportation, and the fourth scenario, to reduce emissions and congestion from freight, including a combination of incentives to shift travel to lower-emissions modes, as well as clean technology to maximize the emissions benefits of that mode shift.
Scenarios 5, 6, and 9 focus on different geographic scales. Scenario 5 focuses on reducing congestion and emissions for a corridor or activity center, using a combination of traffic flow improvements and demand reduction. Scenario 6 similarly focuses on congestion, but at a regional or statewide level. Scenario 9 focuses on projects suitable for rural areas and small communities.
Scenarios 7 and 8 focus on specific air quality problems for the pollutants of most common concern in the United States today. Scenario 7 includes project types that reduce particulate matter and NOx, which tend to have localized health impacts. Scenario 8 includes project types that reduce precursors to ozone formation at a regional scale. These can include both demand reduction and clean technology strategies.
This is an example description of the scenario for expanding commute options.
Supporting project types may include travel demand management, transit improvements, carpooling and vanpooling, public education and outreach, transportation management associations, and training.
Having additional multimodal options, funded by multiple CMAQ projects, can increase the likelihood of using modes other than single-occupancy vehicle by providing travelers with multiple options.
Information and institutional mechanisms, such as transportation management associations, can further support mode shift.
Examples include regionally coordinated projects that include multiple mode shift or demand reduction strategies.
These types of projects would reduce light-duty VMT and would therefore reduce congestion and emissions in proportion to the VMT reduction. It is possible there may be some additional emissions associated with new transit service.
While these project types are most relevant to this goal and most likely to be effective in urban and suburban areas with more density and travel options, statewide programs can also support this strategy across multiple parts of a State.
This is a sample project menu for the example strategy of expanding commute options, at a metropolitan scale of application.
Projects might include staffing and training for a regional TDM program and for local TMAs; resources for guaranteed ride home, teleworking, and carpooling and vanpooling; innovative transit projects serving commuters; HOV lanes; parking cash-out pilots; and trip reduction ordinances.
An MPO would not need to implement all of these projects to achieve synergies – this is just a menu of possible projects from which to choose. There may be others as well. And as noted earlier, MPOs and States should consult with FHWA regarding eligibility questions on any selected projects.
This is another example description, in this case of the scenario for reducing PM and NOx emissions from heavy duty vehicles.
Types of supporting projects might include diesel retrofit or truck technology, idle reduction, public education and outreach, training, and inspection and maintenance programs focused on heavy-duty vehicles.
Synergies may be achieved through coordination of purchasing, and through the growth of institutional knowledge on the most effective technologies for a specific use case and operating conditions.
Examples of projects may include the most cost-effective PM or NOx control projects, implemented on vehicles serving heavily populated areas.
These projects may be applicable at any geographic scale, but are especially suited for PM nonattainment areas, and in the vicinity of communities where health concerns are expressed.
This is a sample project menu for the example strategy of reducing PM and NOx emissions, at a statewide scale of application.
Examples included here are diesel retrofits and new hybrid electric equipment on trucks and locomotives active in urban areas; programs and training for program staff to select and implement clean technology; and IM programs to identify and repair high emitting vehicles.
In conclusion, we have hypothesized that CMAQ projects may have synergistic effects that increase emissions and/or congestion relief benefits. However, we found little information to quantify synergistic benefits, as this is rarely done in practice.
This project proposes groupings of CMAQ projects that are likely to provide synergies with respect to congestion and/or emissions reduction, and presents sample menus of projects for both metropolitan and statewide application.
Further testing will be needed to measure the extent to which synergies might be achieved in practice.
You can find the report, and other resources on the CMAQ program, on FHWA's website.
That concludes our presentation. Thank you for your time and interest!
