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The Congestion Mitigation and Air Quality Improvement Program


Note: This information was archived in September 2013. For current information, see

Because CMAQ funds are intended to improve air quality, funds must be spent in nonattainment or maintenance areas. A nonattainment area is an area formally designated (in the Code of Federal Regulations) by EPA as not meeting the NAAQS. A maintenance area is an area that was nonattainment but has subsequently attained the NAAQS and was officially redesignated to attainment by EPA.

The CMAQ program strives to reduce transportation-related emissions by providing State DOTs and local governments options to fund different emission reduction strategies. For example, the CMAQ Program enables communities to increase public awareness concerning the links between transportation choices and air pollutions; provide technological applications to improve transportation system efficiency; increase transit services; or implement "Ozone Action" programs. Many of these activities could be Transportation Control Measures (TCMs). Most of the eligible categories of CMAQ projects are TCM-type activities and include a wide variety of measures to decrease vehicle emissions, primarily by reducing the total amount of vehicle miles traveled (VMT) in an area. Certain projects are ineligible for CMAQ funds. Legislative prohibitions exclude vehicle retirement programs and highway capacity expansion projects. Policy considerations exclude highway maintenance and reconstruction projects because these activities preserve existing levels of service and are unlikely to contribute to further improvements in air quality.

Transit and Public Transportation Programs

CMAQ funds may be used to support the use of public transportation. There are three broad categories of transit projects or programs that are eligible for funding: service or system expansion; provision of new transit service; and financial incentives to use existing transit services. Service expansion strives to attract new users, typically by providing new transit facilities or additional transit vehicles. Improving intermodal connections in the major urban areas has been a focus since ISTEA and these projects are generally eligible for CMAQ funding.

The start-up of new transit service (e.g., new express bus routes or new shuttle service linking major activity centers) is supported under the CMAQ program in an effort to tap new markets for transit. While CMAQ cannot be a permanent source of funding for transit service, the goal is to encourage experimentation to determine whether new types of services are viable.

Financial incentive strategies attempt to encourage transit use, and include innovative fare policies as part of an overall effort to reduce exceedances of the air quality standards. Under specific conditions, CMAQ may be used to offset the cost of offering reduced or free transit fares. This can be done when the subsidized fare is an element of an overall, area wide strategy for reducing emissions during peak periods of ozone pollution.

Noteworthy transit success stories which were partially CMAQ-funded include the St. Louis Metrolink Program, an 18-mile light transit line that connects suburban communities with the city. Another innovative project was the Boulder, Colorado Hop and Skip Community Transit System. The program received the 1999 FHWA Environmental Excellence Award.

Cover of Hop & Skip Routes & Schedual Information

City of Boulder Special Transit Regional Transportation District 8

The HOP and the SKIP transit services are helping the city of Boulder meet its clean air and congestion relief goals. The services provide easy access and high frequency service for citizens and commuters in Boulder, and they have received widespread community support. The HOP shuttle circulates through three main activity centers. The SKIP provides service that connects residents to employment centers and retail districts along the route. Each day, the HOP and SKIP provide service for close to 10,000 riders. Through partnerships, creative planning, and public involvement, the transit services demonstrate how citizens working with local government can set up a successful, cost-effective, and community-oriented transit system

Traffic Flow Improvements

people monitoring traffic with computers and large wall mounted screens

This strategy reduces emissions by promoting efficient traffic movement, thereby reducing unproductive travel delays and emissions resulting from engine idling. There are many ways to reduce and improve air quality by improving traffic flow. These include: traffic signal synchronization, channelization (to separate turning movements, for example), high occupancy vehicle lanes, and transportation management improvements. Of particular note are Intelligent Transportation Systems (ITS). The ITS efforts, using the very latest technologies, may be among the most innovative traffic flow improvement activities that are funded by CMAQ. In Fiscal Year (FY) 1997 the majority of CMAQ funds went to traffic flow improvements for the first time in program history, and much of this growth can be attributed to increased interest in ITS activities. FY 1996 and FY 1997 CMAQ funds were used for ITS projects that range from the ITS Early Deployment Plan in New York or the Traffic Operations Centers in New Jersey, Georgia and California to placing fiber optic cables in Texas and Kentucky's deployment of the Interstate Traffic Management Program.

Travel Demand Management Strategies

people entering bus

The demand for transportation can be moderated by adopting policy incentives that minimize the aggregate number of single occupancy vehicle trips and miles traveled. These strategies have grown substantially over the years and many metropolitan areas employ them to good advantage. Guaranteed Ride Home programs, employer outreach, public education, telecommuting, transportation management organizations, and other alternatives are also used to encourage trip reduction.

Ride Sharing Programs

Ride sharing programs are designed to increase vehicle occupancy in an attempt to reduce emissions. This can be achieved by minimizing the total number of vehicles on the road and these programs are most effective for commuting purposes. Ride sharing programs tend to be most effective when participants save time or money by ridesharing, for example when high occupancy vehicle lanes are available that reward those traveling with 2 persons or more in a vehicle through reduced travel times.

Pedestrian and Bicycle Programs

bycyclist and pedestrian talking

No mobile source emissions are produced by travelers using bicycles or walking, therefore, programs that promote these options are eligible for CMAQ funds. The substitution of bicycling and walking for relatively short trips is especially beneficial, because brief automobile trips result in disproportionately large emissions caused by cold engine starts and fuel evaporation after the conclusion of the trip.

Bicycle programs may include the creation of trails, storage facilities, and marketing efforts designed to support bicycles as a form of transportation. The bicycle, as a viable transportation mode, has spurred many communities to incorporate bicycling facilities into urban plans, stimulating the reduction of motor vehicle emissions in some areas.

One such example is the Long Beach Bikestation in California which provides a convenient transfer point for riders on the adjacent light rail line. In addition, the Bikestation includes mechanics on site and provides secure bike lockers and rental bicycles. The Long Beach Bikestation has become a community hub for bicycle advocacy, transit information and community events.

Education and Outreach

CMAQ funding may be used to increase public knowledge of transportation-related emissions and opportunities to reduce them through mitigation strategies and improved transportation choices.

Successful education and outreach projects have included metropolitan public awareness campaigns, such as "Ozone Action" day programs that inform citizens about the causes of rising ozone levels during the day. Other activities have included public-private projects. One project in Houston-Galveston, Texas, assessed public resistance to transit and led to the development of compelling marketing materials, reduced fares and the targeted promotion of transit services and resulted in a significant increase in transit ridership.

Inspection and Maintenance Programs

Poor engine maintenance and malfunctioning of pollution control equipment can significantly increase the amount of emissions released per vehicle. According to EPA analysis, only 10 percent of the vehicles on the road produce 50 percent of the pollution. Consequently, CMAQ funds may be used to introduce, conduct and provide start-up costs for automobile inspection and maintenance programs.

Extreme Cold Start Programs

Several physical factors impact engine performance and increase emissions. Cold temperatures, and cold engine starts increase emissions because specialized exhaust equipment, such as catalytic converters, take time to warm up to the optimum operating temperature. While an important phenomenon everywhere, it is particularly crucial in cold-weather climates. CMAQ funds may be directed towards the development and implementation of programs that are designed to reduce or mitigate excessive cold start emissions. It is estimated that for a five mile trip, the cold car generates about 30 percent more NOx and 60 percent more carbon monoxide than starting the car when it is warm.

Figure 8 9. Trip Emissions
Emissions of a Typical Car on the Road in 1997, for a 5-Mile Trip
Click for data

Alternative "Clean" Fuels

Alternative or clean fuels are defined somewhat differently in the Clean Air Act and Energy Policy Act. But for CMAQ purposes an "alternative" fuel must reduce emissions to be eligible. These fuels can include natural gas, ethanol, methanol, electricity and liquefied propane gas. While a great many transit providers have used CMAQ funds for switching to alternative fuels, eligibility also extends to the purchase of vehicles and refueling equipment for other public agencies as well. And under TEA-21, eligibility can even extend to private companies (see Figure 8).

Public/Private Partnerships

It all adds up to cleaner air full-bus logo

Partnerships between public and private enterprises can leverage scarce funding resources by allowing private firms to own or operate a service developed with public funds. Often, public support is vital for projects that are not yet commercially viable because they lack markets sufficiently developed to stimulate private sector investment. TEA-21 eliminates some of the restrictions that previously limited private participation in emission reduction projects.

Some partnerships are ineligible for public funding because the private participation is mandated by law. CMAQ funds can not be used to help a private entity come into compliance with specific legal requirements, such as Clean Air Act or Energy Policy Act mandates. However, if the private entity clearly goes beyond the requirements, CMAQ funds may be used if the eligibility provisions are met. Furthermore, without public sponsorship or a contractual arrangement between a public agency and a private firm, CMAQ funds cannot be directed to the private sector.

street sweeping trucks

Public agencies interested in a partnership project need to consider several institutional and administrative issues. Federal regulations are often a major challenge to people unfamiliar with the process. Local match provisions, reimbursement conditions, environmental clearances, and other requirements apply regardless of whether a project is implemented by a public or private entity. Public partners need to consider contract administration issues, including the length of a contract, and legal recourse in the event of contract performance deficiencies.

Private corporations interested in partnership arrangements need to be aware of program funding characteristics. Potential funding changes include annual appropriation levels or program cancellation. Private partnerships may need to produce satisfactory financial returns for shareholders, but these returns may be set by regulatory authorities in noncompetitive or monopoly market environments.

Experimental Pilot Projects

The CMAQ Program has proved overall to be a highly successful experiment in Federal transportation funding. However, there are many possible ways to use CMAQ funds in which Federal, State and local authorities may have little experience. Experimental pilot projects are innovative initiatives that are designed to provide a funding mechanism for well thought out strategies that extend beyond current experience and are not explicitly eligible under the law. Before and after evaluations are required to see if the experimental project has produced air quality benefits, and States may not use more than 25 percent of their annual

CMAQ apportionment. Pilot projects are usually unique, with few precedents to guide the proposal and development process, but technical assistance is available from Federal agencies, including FHWA and FTA. Experimental pilots must meet all legal requirements -- they must be reasonably classified as transportation projects; they must show potential to reduce emissions; and they cannot violate any legal restrictions.

Recipient Responsibilities

The project sponsor is usually responsible for assembling the proper documentation for CMAQ proposals. The requirements to apply for CMAQ funds vary by metropolitan area and State. Interested parties should contact their State DOT or MPO to find out the requirements for their nonattainment or maintenance area. Once the project is found eligible by FHWA or FTA, the recipient must follow through by supplying information necessary for the State DOT to adequately develop the required annual report. Every effort should be made by the project sponsors to quantify, or qualitatively assess, (if quantification is impossible), the proposal's benefits.

panel meeting

Reporting Requirements

The CMAQ Guidance requires State DOTs to provide FHWA with annual reports detailing their CMAQ projects. The report should list the CMAQ projects by category, and include information about emission reduction estimates and project costs. Generally, these reports are prepared on a Federal fiscal year basis.

8 Source: FHWA 1999 Environmental Excellence Awards
9 Source: FHWA, Transportation Air Quality Selected Facts and Figures, 1999, page 29

Updated: 9/23/2013
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