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Public-Private Partnerships

What is CMAQ?

The Congestion Mitigation and Air Quality (CMAQ) Improvement Program, provides a flexible funding source for state and local governments to fund transportation projects and programs to help meet the requirements of the Clean Air Act (CAA) and its amendments. CMAQ money supports transportation projects that reduce mobile source emissions in areas designated by the U.S. Environmental Protection Agency (EPA) as in nonattainment or maintenance of national ambient air quality standards. Eligible activities include public-private partnerships, traffic flow improvements, and idle reduction projects, among others.

What are the Key CMAQ Funding Requirements?

A ferry is used as an alternative transportation method.

CMAQ funds must be invested in a state's nonattainment or maintenance area(s). The money must be spent on projects that reduce ozone (O3) precursors – volatile organic compounds (VOCs) and Nitrogen oxides(NOx) – carbon monoxide (CO), or particulate matter (PM) from transportation sources. States without nonattainment or maintenance areas may use their CMAQ or Surface Transportation Programs anywhere in the state. All CMAQ projects must come from a transportation plan and Transportation Improvement Program (TIP). The state transportation department is responsible for distributing CMAQ funds.

All projects must conform to established CMAQ guidance. The federal share for most CMAQ-eligible projects is 80 percent, but state and local officials are encouraged to seek a larger match than required by law. The CMAQ program operates on a reimbursable basis, so funds are not provided until work is completed.

What Is a Public-Private Partnership?

A public-private partnership is an agreement between a government agency and non-government organization to work together to accomplish a goal that benefits both the taxpaying public and the private partner. Public-private partnerships come in many forms and are individually designed to suit the goals and needs of each partner.

There must be an agreement between the parties that specifies the intended use of the CMAQ funding, the roles and responsibilities of the participants, any cost-sharing arrangements among participants for capital investments and/or operating expenses, and who takes ownership of any physical property.

Who Can Participate in CMAQ Public-Private Partnerships?

Fueling the XCELLSIS fuel cell bus with compressed hydrogen. Photograph courtesy of Bob Barnitt, eTIAX LLC. (Department of Energy/National Renewable Energy Laboratory).
An alternative fuel cell bus being fueled with compressed hydrogen.

Public Partners

Eligible public partners include metropolitan planning organizations (MPOs), state or local transportation departments, transit providers, and any other organization that can accept federal transportation funds through their local MPO.

Private Partners

A private partner can be a privately owned company or other non-government entity that wishes to deliver transportation-related projects to reduce emissions, but may not be able to bear the full cost of the project.

Why Would a Public Agency or a Private Partner Participate in a CMAQ Public-Private Partnership?

State and local transportation and environmental agencies are continually seeking new ways of reducing emissions to comply with the Clean Air Act requirements. Some activities and technologies being used or developed by the private sector can help public agencies in this endeavor. Public agencies can gain environmental benefits, technical expertise and financial assistance by partnering with others that are interested in air quality and congestion mitigation.

By partnering with a public agency, a private entity can access technical and regulatory expertise, receive public acknowledgement for its contribution, and benefit from federal CMAQ funds.

What Public-Private Partnership Projects Are Eligible for CMAQ Funds?

Auburn, Maine's Intermodal Freight Transfer Facility celebrates its 75,000th container.
A train freight container facility

A variety of projects lend themselves to partnerships, including fleet conversions to alternative fuels, intermodal freight facilities, and ferry services, to name a few.

To be eligible for CMAQ funds, a partnership project must reduce transportation emissions in nonattainment or maintenance areas. Such projects generally reduce emissions by reducing vehicle travel, or by lowering vehicle emissions directly.

Examples of Successful Public-Private Partnerships

The Intermodal Freight Transfer Facility is owned by the City of Auburn, Maine, and leased to an intermodal transportation firm. The facility is expected to redirect substantial truck traffic to rail. The construction of the facility cost approximately $2.3 million in CMAQ funds, $600,000 in local funds, and $200,000 in private funds. This project's First Phase resulted in an estimated emissions reductions of 7 kg/day VOC and 77 kg/day NOx.

The Knoxville Regional Transportation Planning Organization partnered with an idle reduction firm, and used $1 million in CMAQ funds to install 100 advanced truck stop electrification units to stop diesel engines idling along I-40/I-75 in Knoxville, TN. The project resulted in emission reductions of 25 kg/day CO, 60 kg/day NOx, 1.6 kg/day PM, and 3 kg/day VOC, during 826 days of use.

Houston-Galveston Area Alternative Fuel Vehicle Program: The Houston Galveston Area Councils Alternative Fuel Vehicle Program (AFVP) provides funding to government and private entities to assist them in purchasing and using alternative fuel vehicles. CMAQ funding is available for up to 75 percent of AFVP project costs. Of the projects completed, $2.5 million in CMAQ funding were used. Ozone related emissions reductions were estimated to be 197 kg/day.

A simple window adapter makes this electrification system compaible with many models of long-haul trucks. Photograph courtesy of IdleAir.
A truck window adapter electrification system

For more information, please contact:
U.S. Department of Transportation Federal Highway Administration
Office of Natural and Human Environment
400 7th Street, S.W., Room 3240
Washington, D.C. 20590; 202-366-6724


This document is disseminated under the sponsorship of the U.S. Department of Transportation in the interest of information exchange. The U.S. Government assumes no liability for use of the information contained in this document. This report does not constitute a standard, specification or regulation.

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It all adds up to cleaner air


October 2005

Updated: 7/6/2011
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