---
kind: "section"
citation: "23 U.S.C. § 149"
title: "23"
title_heading: "Highways"
number: "149"
heading: "Congestion mitigation and air quality improvement program"
release: "119-102"
date: "2026-07-12"
url: "https://uscodex.org/usc/23/149"
units:
  - "Chapter 1 — Federal-Aid Highways"
---

# §149. Congestion mitigation and air quality improvement program

- (a) **Establishment.—** The [Secretary](/usc/23/101.md?p=a-27) shall establish and implement a congestion mitigation and air quality improvement program in accordance with this section.
- (b) **Eligible Projects.—** Except as provided in subsections [(d)](#d) and [(m)(1)(B)(ii)](#m-1-B-ii), a [State](/usc/23/101.md?p=a-28) may obligate funds apportioned to it under [section 104(b)(4)](/usc/23/104.md?p=b-4) for the congestion mitigation and air quality improvement program only for a transportation [project](/usc/23/101.md?p=a-20) or program if the [project](/usc/23/101.md?p=a-20) or program is for an area in the [State](/usc/23/101.md?p=a-28) that is or was designated as a nonattainment area for ozone, carbon monoxide, or particulate matter under section 107(d) of the Clean Air Act ([42 U.S.C. 7407(d)](/usc/42/7407.md?p=d)) and classified pursuant to section 181(a), 186(a), 188(a), or 188(b) of the Clean Air Act ([42 U.S.C. 7511(a)](/usc/42/7511.md?p=a), 7512(a), 7513(a), or 7513(b)) or is or was designated as a nonattainment area under such [section 107(d)](/usc/23/107.md?p=d) after December 31, 1997, or is required to prepare, and file with the Administrator of the Environmental Protection Agency, [maintenance](/usc/23/101.md?p=a-13) plans under the Clean Air Act ([42 U.S.C. 7401](/usc/42/7401.md) et seq.) and—
  - (1)
    - (A)
      - (i) if the [Secretary](/usc/23/101.md?p=a-27), after consultation with the Administrator determines, on the basis of information published by the Environmental Protection Agency pursuant to section 108(f)(1)(A) of the Clean Air Act (other than clause (xvi)) that the [project](/usc/23/101.md?p=a-20) or program is likely to contribute to—
        - (I) the attainment of a national ambient air quality standard in the designated nonattainment area; or
        - (II) the [maintenance](/usc/23/101.md?p=a-13) of a national ambient air quality standard in a [maintenance area](/usc/23/101.md?p=a-14); and
      - (ii) a high level of effectiveness in reducing air pollution, in cases of [projects](/usc/23/101.md?p=a-20) or programs where sufficient information is available in the database established pursuant to [subsection (h)](#h) to determine the relative effectiveness of such [projects](/usc/23/101.md?p=a-20) or programs; or,
    - (B) in any case in which such information is not available, if the [Secretary](/usc/23/101.md?p=a-27), after such consultation, determines that the [project](/usc/23/101.md?p=a-20) or program is part of a program, method, or strategy described in such [section 108(f)(1)(A)](/usc/23/108.md);
  - (2) if the [project](/usc/23/101.md?p=a-20) or program is included in a [State](/usc/23/101.md?p=a-28) implementation plan that has been approved pursuant to the Clean Air Act and the [project](/usc/23/101.md?p=a-20) will have air quality benefits;
  - (3) the [Secretary](/usc/23/101.md?p=a-27), after consultation with the Administrator of the Environmental Protection Agency, determines that the [project](/usc/23/101.md?p=a-20) or program is likely to contribute to the attainment or [maintenance](/usc/23/101.md?p=a-13) of a national ambient air quality standard, whether through reductions in vehicle miles traveled, fuel consumption, or through other factors;
  - (4) to establish or operate a traffic monitoring, management, and control facility or program, including advanced [truck stop electrification systems](/usc/23/101.md?p=a-34), if the [Secretary](/usc/23/101.md?p=a-27), after consultation with the Administrator of the Environmental Protection Agency, determines that the facility or program is likely to contribute to the attainment or [maintenance](/usc/23/101.md?p=a-13) in the area of a national ambient air quality standard;
  - (5) if the program or [project](/usc/23/101.md?p=a-20) improves traffic flow, including [projects](/usc/23/101.md?p=a-20) to improve signalization, construct high occupancy vehicle lanes, improve intersections, add turning lanes, improve [transportation systems management and operations](/usc/23/101.md?p=a-32-A) that mitigate congestion and improve air quality, and implement intelligent transportation system strategies and such other [projects](/usc/23/101.md?p=a-20) that are eligible for assistance under this section on the day before the date of enactment of this paragraph, including programs or [projects](/usc/23/101.md?p=a-20) to improve incident and emergency response or improve mobility, such as through real-time traffic, transit, and multimodal traveler information;
  - (6) if the [project](/usc/23/101.md?p=a-20) or program involves the purchase of integrated, interoperable emergency communications equipment;
  - (7) if the [project](/usc/23/101.md?p=a-20) or program shifts traffic demand to nonpeak hours or other transportation modes, increases vehicle occupancy rates, or otherwise reduces demand for roads through such means as telecommuting, ridesharing, carsharing, shared micromobility (including bikesharing and shared scooter systems), alternative work hours, and pricing;
  - (8) if the [project](/usc/23/101.md?p=a-20) or program is for—
    - (A) the purchase of diesel replacements or retrofits that are—
      - (i) verified technologies (as defined in section 791 of the Energy Policy Act of 2005 ([42 U.S.C. 16131](/usc/42/16131.md))) for motor vehicles (as defined in section 216 of the Clean Air Act ([42 U.S.C. 7550](/usc/42/7550.md))); or
      - (ii) verified technologies (as defined in section 791 of the Energy Policy Act of 2005 ([42 U.S.C. 16131](/usc/42/16131.md))) for non-road vehicles and non-road engines (as defined in section 216 of the Clean Air Act ([42 U.S.C. 7550](/usc/42/7550.md))) that are used in [construction](/usc/23/101.md?p=a-4) [projects](/usc/23/101.md?p=a-20) or port-related freight operations that are—
        - (I) located in nonattainment or [maintenance areas](/usc/23/101.md?p=a-14) for ozone, PM<sub>10</sub>, or PM<sub>2.5</sub> (as defined under the Clean Air Act ([42 U.S.C. 7401](/usc/42/7401.md) et seq.)); and
        - (II) funded, in whole or in part, under this title or [chapter 53](/usc/49/chstIII/ch53.md) of title 49;
    - (B) the conduct of outreach activities that are designed to provide information and technical assistance to the owners and operators of diesel equipment and vehicles regarding the purchase and installation of diesel replacements or retrofits; or
    - (C) the purchase of medium- or heavy-duty zero emission vehicles and related charging equipment;
  - (9) if the [project](/usc/23/101.md?p=a-20) or program is for the installation of vehicle-to-infrastructure communication equipment;
  - (10) if the [project](/usc/23/101.md?p=a-20) is for the modernization or rehabilitation of a lock and dam that—
    - (A) is functionally connected to the [Federal-aid highway](/usc/23/101.md?p=a-6) system; and
    - (B) the [Secretary](/usc/23/101.md?p=a-27) determines is likely to contribute to the attainment or [maintenance](/usc/23/101.md?p=a-13) of a national ambient air quality standard; or
  - (11) if the [project](/usc/23/101.md?p=a-20) is on a marine [highway](/usc/23/101.md?p=a-11) corridor, connector, or crossing designated by the [Secretary](/usc/23/101.md?p=a-27) under [section 55601(c) of title 46](/usc/46/55601.md?p=c) (including an inland waterway corridor, connector, or crossing) that—
    - (A) is functionally connected to the [Federal-aid highway](/usc/23/101.md?p=a-6) system; and
    - (B) the [Secretary](/usc/23/101.md?p=a-27) determines is likely to contribute to the attainment or [maintenance](/usc/23/101.md?p=a-13) of a national ambient air quality standard.
- (c) **Special Rules.—**
  - (1) **Projects for pm–10 nonattainment areas.—** A [State](/usc/23/101.md?p=a-28) may obligate funds apportioned to the [State](/usc/23/101.md?p=a-28) under [section 104(b)(4)](/usc/23/104.md?p=b-4) for a [project](/usc/23/101.md?p=a-20) or program for an area that is nonattainment for ozone or carbon monoxide, or both, and for PM–10 resulting from transportation activities, without regard to any limitation of the Department of Transportation relating to the type of ambient air quality standard such [project](/usc/23/101.md?p=a-20) or program addresses.
  - (2) **Electric vehicle and natural gas vehicle infrastructure.—** A [State](/usc/23/101.md?p=a-28) may obligate funds apportioned under [section 104(b)(4)](/usc/23/104.md?p=b-4) for a [project](/usc/23/101.md?p=a-20) or program to establish electric vehicle charging stations or natural gas vehicle refueling stations for the use of battery powered or natural gas fueled trucks or other motor vehicles at any location in the [State](/usc/23/101.md?p=a-28) (giving priority to corridors designated under [section 151](/usc/23/151.md)) except that such stations may not be established or supported where commercial establishments serving motor vehicle users are prohibited by [section 111 of title 23](/usc/23/111.md), United States Code.
  - (3) **HOV facilities.—** No funds may be provided under this section for a [project](/usc/23/101.md?p=a-20) which will result in the [construction](/usc/23/101.md?p=a-4) of new capacity available to single occupant vehicles unless the [project](/usc/23/101.md?p=a-20) consists of a high occupancy vehicle facility available to single occupant vehicles only at other than peak travel times.
  - (4) **Locks and dams; marine highways.—** For each fiscal year, a [State](/usc/23/101.md?p=a-28) may not obligate more than 10 percent of the funds apportioned to the [State](/usc/23/101.md?p=a-28) under [section 104(b)(4)](/usc/23/104.md?p=b-4) for [projects](/usc/23/101.md?p=a-20) described in paragraphs [(10)](#b-10) and [(11)](#b-11) of subsection (b).
- (d) **States Flexibility.—**
  - (1) **States without a nonattainment area.—** If a [State](/usc/23/101.md?p=a-28) does not have, and never has had, a nonattainment area designated under the Clean Air Act ([42 U.S.C. 7401](/usc/42/7401.md) et seq.), the [State](/usc/23/101.md?p=a-28) may use funds apportioned to the [State](/usc/23/101.md?p=a-28) under [section 104(b)(4)](/usc/23/104.md?p=b-4) for any [project](/usc/23/101.md?p=a-20) in the [State](/usc/23/101.md?p=a-28) that—
    - (A) would otherwise be eligible under [subsection (b)](#b) as if the [project](/usc/23/101.md?p=a-20) were carried out in a nonattainment or [maintenance area](/usc/23/101.md?p=a-14); or
    - (B) is eligible under the surface transportation block grant program under section 133.
  - (2) **States with a nonattainment area.—**
    - (A) **In general.—** If a [State](/usc/23/101.md?p=a-28) has a nonattainment area or [maintenance area](/usc/23/101.md?p=a-14) and received funds in fiscal year 2009 under [section 104(b)(2)(D)](/usc/23/104.md), as in effect on the day before the date of enactment of the MAP–21, above the amount of funds that the [State](/usc/23/101.md?p=a-28) would have received based on the nonattainment and [maintenance area](/usc/23/101.md?p=a-14) population of the [State](/usc/23/101.md?p=a-28) under subparagraphs [(B)](/usc/23/104.md) and [(C)](/usc/23/104.md) of section 104(b)(2), as in effect on the day before the date of enactment of the MAP–21, the [State](/usc/23/101.md?p=a-28) may use for any [project](/usc/23/101.md?p=a-20) that would otherwise be eligible under [subsection (b)](#b) if the [project](/usc/23/101.md?p=a-20) were carried out in a nonattainment or [maintenance area](/usc/23/101.md?p=a-14) or is eligible under the surface transportation block grant program under [section 133](/usc/23/133.md) an amount of funds apportioned to such [State](/usc/23/101.md?p=a-28) under [section 104(b)(4)](/usc/23/104.md?p=b-4) that is equal to the product obtained by multiplying—
      - (i) the amount apportioned to such [State](/usc/23/101.md?p=a-28) under [section 104(b)(4)](/usc/23/104.md?p=b-4) (excluding the amount of funds reserved under [subsection (k)(1)](#k-1)); by
      - (ii) the ratio calculated under [subparagraph (B)](#d-2-B).
    - (B) **Ratio.—** For purposes of this paragraph, the ratio shall be calculated as the proportion that—
      - (i) the amount for fiscal year 2009 such [State](/usc/23/101.md?p=a-28) was permitted by [section 149(c)(2)](#c-2), as in effect on the day before the date of enactment of the MAP–21, to obligate in any area of the [State](/usc/23/101.md?p=a-28) for [projects](/usc/23/101.md?p=a-20) eligible under [section 133](/usc/23/133.md), as in effect on the day before the date of enactment of the MAP–21; bears to
      - (ii) the total [apportionment](/usc/23/101.md?p=a-1) to such [State](/usc/23/101.md?p=a-28) for fiscal year 2009 under [section 104(b)(2)](/usc/23/104.md?p=b-2), as in effect on the day before the date of enactment of the MAP–21.
  - (3) **Changes in designation.—** If a new nonattainment area is designated or a previously designated nonattainment area is redesignated as an attainment area in a [State](/usc/23/101.md?p=a-28) under the Clean Air Act ([42 U.S.C. 7401](/usc/42/7401.md) et seq.), the [Secretary](/usc/23/101.md?p=a-27) shall modify, in a manner consistent with the approach that was in effect on the day before the date of enactment of MAP–21, the amount such [State](/usc/23/101.md?p=a-28) is permitted to obligate in any area of the [State](/usc/23/101.md?p=a-28) for [projects](/usc/23/101.md?p=a-20) eligible under section 133.
- (e) **Applicability of Planning Requirements.—** Programming and expenditure of funds for [projects](/usc/23/101.md?p=a-20) under this section shall be consistent with the requirements of sections [134](/usc/23/134.md) and [135](/usc/23/135.md) of this title.
- (f) **Partnerships With Nongovernmental Entities.—**
  - (1) **In general.—** Notwithstanding any other provision of this title and in accordance with this subsection, a metropolitan planning organization, [State transportation department](/usc/23/101.md?p=a-31), or other [project](/usc/23/101.md?p=a-20) sponsor may enter into an agreement with any public, private, or nonprofit entity to cooperatively implement any [project](/usc/23/101.md?p=a-20) carried out under this section.
  - (2) **Forms of participation by entities.—** Participation by an entity under [paragraph (1)](#f-1) may consist of—
    - (A) ownership or operation of any land, facility, vehicle, or other physical asset associated with the [project](/usc/23/101.md?p=a-20);
    - (B) cost sharing of any [project](/usc/23/101.md?p=a-20) expense;
    - (C) carrying out of administration, [construction](/usc/23/101.md?p=a-4) management, [project](/usc/23/101.md?p=a-20) management, [project](/usc/23/101.md?p=a-20) operation, or any other management or operational duty associated with the [project](/usc/23/101.md?p=a-20); and
    - (D) any other form of participation approved by the [Secretary](/usc/23/101.md?p=a-27).
  - (3) **Allocation to entities.—** A [State](/usc/23/101.md?p=a-28) may allocate funds apportioned under [section 104(b)(4)](/usc/23/104.md?p=b-4) to an entity described in [paragraph (1)](#f-1).
  - (4) **Alternative fuel projects.—** In the case of a [project](/usc/23/101.md?p=a-20) that will provide for the use of alternative fuels by privately owned vehicles or vehicle fleets, activities eligible for funding under this subsection—
    - (A) may include the costs of vehicle refueling infrastructure, including infrastructure that would support the development, production, and use of emerging technologies that reduce emissions of air pollutants from motor vehicles and nonroad vehicles and nonroad engines used in [construction](/usc/23/101.md?p=a-4) [projects](/usc/23/101.md?p=a-20) or port-related freight operations, and other capital investments associated with the [project](/usc/23/101.md?p=a-20);
    - (B) shall include only the incremental cost of an alternative fueled vehicle, as compared to a conventionally fueled vehicle, that would otherwise be borne by a private party; and
    - (C) shall apply other governmental financial purchase contributions in the calculation of net incremental cost.
  - (5) **Prohibition on federal participation with respect to required activities.—** A Federal participation payment under this subsection may not be made to an entity to fund an obligation imposed under the Clean Air Act ([42 U.S.C. 7401](/usc/42/7401.md) et seq.) or any other Federal law.
- (g) **Cost-Effective Emission Reduction Guidance.—**
  - (1) **Definitions.—** In this subsection, the following definitions apply:
    - (A) **Administrator.—** The term “Administrator” means the Administrator of the Environmental Protection Agency.
    - (B) **Diesel replacement or retrofit.—** The term “diesel replacement or retrofit” means a replacement or retrofit, repowering, rebuilding, after treatment, or other technology, as determined by the Administrator.
  - (2) **Emission reduction guidance.—** The Administrator, in consultation with the [Secretary](/usc/23/101.md?p=a-27), shall publish a list of diesel replacement or retrofit technologies and supporting technical information for—
    - (A) diesel emission reduction technologies certified or verified by the Administrator, the California Air Resources Board, or any other entity recognized by the Administrator for the same purpose;
    - (B) diesel emission reduction technologies identified by the Administrator as having an application and approvable test plan for verification by the Administrator or the California Air Resources Board that is submitted not later than 18 months of the date of enactment of this subsection;
    - (C) available information regarding the emission reduction effectiveness and cost effectiveness of technologies identified in this paragraph, taking into consideration air quality and health effects.
  - (3) **Priority consideration.—** [States](/usc/23/101.md?p=a-28) and metropolitan planning organizations shall give priority in areas designated as nonattainment or [maintenance](/usc/23/101.md?p=a-13) for PM2.5 under the Clean Air Act ([42 U.S.C. 7401](/usc/42/7401.md) et seq.) in distributing funds received for congestion mitigation and air quality [projects](/usc/23/101.md?p=a-20) and programs from [apportionments](/usc/23/101.md?p=a-1) under [section 104(b)(4)](/usc/23/104.md?p=b-4) to [projects](/usc/23/101.md?p=a-20) that are proven to reduce PM2.5, including diesel replacements or retrofits.
  - (4) **No effect on authority or restrictions.—** Nothing in this subsection modifies or otherwise affects any authority or restriction established under the Clean Air Act ([42 U.S.C. 7401](/usc/42/7401.md) et seq.) or any other law (other than provisions of this title relating to congestion mitigation and air quality).
- (h) **Interagency Consultation.—** The [Secretary](/usc/23/101.md?p=a-27) shall encourage [States](/usc/23/101.md?p=a-28) and metropolitan planning organizations to consult with [State](/usc/23/101.md?p=a-28) and local air quality agencies in nonattainment and [maintenance areas](/usc/23/101.md?p=a-14) on the estimated emission reductions from proposed congestion mitigation and air quality improvement programs and [projects](/usc/23/101.md?p=a-20).
- (i) **Evaluation and Assessment of Projects.—**
  - (1) **Database.—**
    - (A) **In general.—** Using appropriate assessments of [projects](/usc/23/101.md?p=a-20) funded under the congestion mitigation and air quality program and results from other research, the [Secretary](/usc/23/101.md?p=a-27) shall maintain and disseminate a cumulative database describing the impacts of the [projects](/usc/23/101.md?p=a-20), including specific information about each [project](/usc/23/101.md?p=a-20), such as the [project](/usc/23/101.md?p=a-20) name, location, sponsor, cost, and, to the extent already measured by the [project](/usc/23/101.md?p=a-20) sponsor, cost-effectiveness, based on reductions in congestion and emissions.
    - (B) **Availability.—** The database shall be published or otherwise made readily available by the [Secretary](/usc/23/101.md?p=a-27) in electronically accessible format and means, such as the Internet, for public review.
  - (2) **Cost effectiveness.—**
    - (A) **In general.—** The [Secretary](/usc/23/101.md?p=a-27), in consultation with the Administrator of the Environmental Protection Agency, shall evaluate [projects](/usc/23/101.md?p=a-20) on a periodic basis and develop a table or other similar medium that illustrates the cost-effectiveness of a range of [project](/usc/23/101.md?p=a-20) types eligible for funding under this section as to how the [projects](/usc/23/101.md?p=a-20) mitigate congestion and improve air quality.
    - (B) **Contents.—** The table described in [subparagraph (A)](#i-2-A) shall show measures of cost-effectiveness, such as dollars per ton of emissions reduced, and assess those measures over a variety of timeframes to capture impacts on the planning timeframes outlined in section 134.
    - (C) **Use of table.—** [States](/usc/23/101.md?p=a-28) and metropolitan planning organizations shall consider the information in the table when selecting [projects](/usc/23/101.md?p=a-20) or developing performance plans under [subsection (l)](#l).
- (j) **Optional Programmatic Eligibility.—**
  - (1) **In general.—** At the discretion of a metropolitan planning organization, a technical assessment of a selected program of [projects](/usc/23/101.md?p=a-20) may be conducted through modeling or other means to demonstrate the emissions reduction projection required under this section.
  - (2) **Applicability.—** If an assessment described in [paragraph (1)](#j-1) successfully demonstrates an emissions reduction, all [projects](/usc/23/101.md?p=a-20) included in such assessment shall be eligible for obligation under this section without further demonstration of emissions reduction of individual [projects](/usc/23/101.md?p=a-20) included in such assessment.
- (k) **Priority for Use of Funds in PM2.5 Areas.—**
  - (1) **In general.—** For any [State](/usc/23/101.md?p=a-28) that has a nonattainment or [maintenance area](/usc/23/101.md?p=a-14) for fine particulate matter, an amount equal to 25 percent of the funds apportioned to each [State](/usc/23/101.md?p=a-28) under [section 104(b)(4)](/usc/23/104.md?p=b-4) for a nonattainment or [maintenance area](/usc/23/101.md?p=a-14) that are based all or in part on the weighted population of such area in fine particulate matter nonattainment shall be obligated to [projects](/usc/23/101.md?p=a-20) that—
    - (A) reduce such fine particulate matter emissions in such area, including diesel replacements or retrofits; and
    - (B) to the extent practicable, prioritize benefits to disadvantaged communities or low-income populations living in, or immediately adjacent to, such area.
  - (2) **Construction equipment and vehicles.—** In order to meet the requirements of [paragraph (1)](#k-1), a [State](/usc/23/101.md?p=a-28) or metropolitan planning organization may elect to obligate funds to install diesel emission control technology on nonroad diesel equipment or on-road diesel equipment that is operated on a [highway](/usc/23/101.md?p=a-11) [construction](/usc/23/101.md?p=a-4) [project](/usc/23/101.md?p=a-20) within a PM2.5 nonattainment or [maintenance area](/usc/23/101.md?p=a-14).
  - (3) **PM2.5 nonattainment and maintenance in low population density states.—**
    - (A) **Exception.—** In any [State](/usc/23/101.md?p=a-28) with a population density of 80 or fewer persons per square mile of land area, based on the most recent decennial census, the requirements under [subsection (g)(3)](#g-3) and paragraphs (1) and (2) of this subsection shall not apply to a nonattainment or [maintenance area](/usc/23/101.md?p=a-14) in the [State](/usc/23/101.md?p=a-28) if—
      - (i) the nonattainment or [maintenance area](/usc/23/101.md?p=a-14) does not have [projects](/usc/23/101.md?p=a-20) that are part of the emissions analysis of a metropolitan transportation plan or transportation improvement program; and
      - (ii) regional motor vehicle emissions are an insignificant contributor to the air quality problem for PM2.5 in the nonattainment or [maintenance area](/usc/23/101.md?p=a-14).
    - (B) **Calculation.—** If [subparagraph (A)](#k-3-A) applies to a nonattainment or [maintenance area](/usc/23/101.md?p=a-14) in a [State](/usc/23/101.md?p=a-28), the percentage of the PM2.5 set-aside under [paragraph (1)](#k-1) shall be reduced for that [State](/usc/23/101.md?p=a-28) proportionately based on the weighted population of the area in fine particulate matter nonattainment.
  - (4) **Port-related equipment and vehicles.—** To meet the requirements under [paragraph (1)](#k-1), a [State](/usc/23/101.md?p=a-28) or metropolitan planning organization may elect to obligate funds to the most cost-effective [projects](/usc/23/101.md?p=a-20) to reduce emissions from port-related landside nonroad or on-road equipment that is operated within the boundaries of a PM2.5 nonattainment or [maintenance area](/usc/23/101.md?p=a-14).
- (l) **Performance Plan.—**
  - (1) **In general.—** Each metropolitan planning organization serving a transportation management area (as defined in [section 134](/usc/23/134.md)) with a population over 1,000,000 people representing a nonattainment or [maintenance area](/usc/23/101.md?p=a-14) shall develop a performance plan that—
    - (A) includes an area baseline level for traffic congestion and on-road mobile source emissions for which the area is in nonattainment or [maintenance](/usc/23/101.md?p=a-13);
    - (B) describes progress made in achieving the air quality and traffic congestion performance targets described in [section 150(d)](/usc/23/150.md?p=d); and
    - (C) includes a description of [projects](/usc/23/101.md?p=a-20) identified for funding under this section and how such [projects](/usc/23/101.md?p=a-20) will contribute to achieving emission and traffic congestion reduction targets.
  - (2) **Updated plans.—** Performance plans shall be updated biennially and include a separate report that assesses the progress of the program of [projects](/usc/23/101.md?p=a-20) under the previous plan in achieving the air quality and traffic congestion targets of the previous plan.
  - (3) **Assistance to metropolitan planning organizations.—**
    - (A) **In general.—** On the request of a metropolitan planning organization, the [Secretary](/usc/23/101.md?p=a-27) may assist the metropolitan planning organization tracking progress made in minority or low-income populations as part of a performance plan under this subsection.
    - (B) **Savings provision.—** Nothing in this paragraph provides the [Secretary](/usc/23/101.md?p=a-27) the authority—
      - (i) to change the performance measures under [section 150(c)(5)](/usc/23/150.md?p=c-5) or the performance targets established under section [134(h)(2)](/usc/23/134.md?p=h-2) or [150(d)](/usc/23/150.md?p=d); or
      - (ii) to establish any other Federal requirement.
- (m) **Operating Assistance.—**
  - (1) **In general.—** A [State](/usc/23/101.md?p=a-28) may obligate funds apportioned under [section 104(b)(4)](/usc/23/104.md?p=b-4) in an area of the [State](/usc/23/101.md?p=a-28) that is otherwise eligible for obligations of such funds for operating costs—
    - (A) under [chapter 53](/usc/49/chstIII/ch53.md) of title 49; or
    - (B) on—
      - (i) a system for which CMAQ funding was eligible, made available, obligated, or expended in fiscal year 2012; or
      - (ii) a [State](/usc/23/101.md?p=a-28)-supported Amtrak route with a valid cost-sharing agreement under [section 209](/usc/23/209.md) of the Passenger Rail Investment and Improvement Act of 2008 ([49 U.S.C. 24101](/usc/49/24101.md) note; Public Law 110–432) and no current nonattainment areas under [subsection (d)](#d).
  - (2) **No time limitation.—** Operating assistance provided under [paragraph (1)](#m-1) shall have no imposed time limitation if the operating assistance is for—
    - (A) a route described in [subparagraph (B)](#m-2-B) of that paragraph; or
    - (B) a transit system that is located in—
      - (i) a non-[urbanized area](/usc/23/101.md?p=a-36); or
      - (ii) an [urbanized area](/usc/23/101.md?p=a-36) with a population of 200,000 or fewer.

## Source credit

(Added Pub. L. 93–87, title I, § 142(a), Aug. 13, 1973, 87 Stat. 272; amended Pub. L. 102–240, title I, § 1008(a), Dec. 18, 1991, 105 Stat. 1932; Pub. L. 102–388, title III, § 380, Oct. 6, 1992, 106 Stat. 1562; Pub. L. 104–59, title III, § 319(a)(1), (b), Nov. 28, 1995, 109 Stat. 588, 589; Pub. L. 104–88, title IV, § 405(a)(2), (b), Dec. 29, 1995, 109 Stat. 956, 957; Pub. L. 105–178, title I, § 1110(a)–(d)(1), June 9, 1998, 112 Stat. 142, 143; Pub. L. 109–59, title I, § 1808(a)–(f), Aug. 10, 2005, 119 Stat. 1461–1463; Pub. L. 112–141, div. A, title I, § 1113(a), (b), July 6, 2012, 126 Stat. 460; Pub. L. 113–76, div. L, title I, § 125, Jan. 17, 2014, 128 Stat. 587; Pub. L. 114–94, div. A, title I, §§ 1109(c)(5), 1114, Dec. 4, 2015, 129 Stat. 1343, 1348; Pub. L. 115–141, div. L, title IV, § 421, Mar. 23, 2018, 132 Stat. 1045; Pub. L. 117–58, div. A, title I, § 11115, Nov. 15, 2021, 135 Stat. 480.)

## Notes

### Editorial Notes

### References in Text

The Clean Air Act, referred to in subsecs. (b), (d)(1), (3), (f)(5), and (g)(3), (4), is act July 14, 1955, ch. 360, 69 Stat. 322, which is classified generally to chapter 85 (§ 7401 et seq.) of Title 42, The Public Health and Welfare. Section 108(f)(1)(A) of the Act is classified to section 7408(f)(1)(A) of Title 42. For complete classification of this Act to the Code, see Short Title note set out under section 7401 of Title 42 and Tables.

The date of enactment of this paragraph, referred to in subsec. (b)(5), is the date of enactment of Pub. L. 105–178, which was approved June 9, 1998.

Sections 104(b)(2), 133, and 149(c)(2), as in effect on the day before the date of enactment of the MAP–21, referred to in subsec. (d)(2), mean section 104(b)(2) of this title, section 133 of this title, and subsec. (c)(2) of this section, respectively, as in effect on the day before the date of enactment of Pub. L. 112–141, which amended section 104 generally, made numerous amendments to section 133, and redesignated subsec. (c) of this section as (d) and struck it out. The date of enactment of the MAP–21 is deemed to be Oct. 1, 2012, see section 3(a), (b) of Pub. L. 112–141, set out as Effective and Termination Dates of 2012 Amendment notes under section 101 of this title.

The day before the date of enactment of MAP–21, referred to in subsec. (d)(3), means the day before the date of enactment of Pub. L. 112–141. See note above.

The date of enactment of this subsection, referred to in subsec. (g)(2)(B), is the date of enactment of Pub. L. 109–59, which was approved Aug. 10, 2005.

Section 209 of the Passenger Rail Investment and Improvement Act of 2008, referred to in subsec. (m), is section 209 of div. B of Pub. L. 110–432, which is set out as a note under section 24101 of Title 49, Transportation.

### Amendments

2021—Subsec. (b). Pub. L. 117–58, § 11115(1)(A), substituted “subsections (d) and (m)(1)(B)(ii)” for “subsection (d)” in introductory provisions.

Subsec. (b)(7). Pub. L. 117–58, § 11115(1)(B), inserted “shared micromobility (including bikesharing and shared scooter systems),” after “carsharing,”.

Subsec. (b)(8)(A). Pub. L. 117–58, § 11115(1)(C)(i)(I), inserted “replacements or” before “retrofits” in introductory provisions.

Subsec. (b)(8)(A)(i). Pub. L. 117–58, § 11115(1)(C)(i)(II), added cl. (i) and struck out former cl. (i) which read as follows: “for motor vehicles (as defined in section 216 of the Clean Air Act (42 U.S.C. 7550)); or”.

Subsec. (b)(8)(B). Pub. L. 117–58, § 11115(1)(C)(ii), inserted “replacements or” before “retrofits”.

Subsec. (b)(8)(C). Pub. L. 117–58, § 11115(1)(C)(i)(III), (iii), added subpar. (C).

Subsec. (b)(10), (11). Pub. L. 117–58, § 11115(1)(D), (E), added pars. (10) and (11).

Subsec. (c)(4). Pub. L. 117–58, § 11115(2), added par. (4).

Subsec. (f)(4)(A). Pub. L. 117–58, § 11115(3), inserted “and nonroad vehicles and nonroad engines used in construction projects or port-related freight operations” after “motor vehicles”.

Subsec. (g)(1)(B). Pub. L. 117–58, § 11115(4)(A), in heading, inserted “replacement or” before “retrofit” and, in text, substituted “The term ‘diesel replacement or retrofit’ means” for “The term ‘diesel retrofit’ means” and inserted “or retrofit” after “replacement”.

Subsec. (g)(2). Pub. L. 117–58, § 11115(4)(B), inserted “replacement or” before “retrofit” in introductory provisions.

Subsec. (g)(3). Pub. L. 117–58, § 11115(4)(C), inserted “replacements or” before “retrofits”.

Subsec. (k)(1). Pub. L. 117–58, § 11115(5), substituted “that—” and subpars. (A) and (B) for “that reduce such fine particulate matter emissions in such area, including diesel retrofits.”

Subsec. (l)(3). Pub. L. 117–58, § 11115(6), added par. (3).

Subsec. (m). Pub. L. 117–58, § 11115(7), added subsec. (m) and struck out former subsec. (m). Prior to amendment, text read as follows: “A State may obligate funds apportioned under section 104(b)(4) in an area of such State that is otherwise eligible for obligations of such funds for operating costs under chapter 53 of title 49 or on a system for which CMAQ funding was made available, obligated or expended in fiscal year 2012, or on a State-Supported Amtrak route with a valid cost-sharing agreement under section 209 of the Passenger Rail Investment and Improvement Act of 2008 and no current nonattainment areas under subsection (d), and shall have no imposed time limitation.”

2018—Subsec. (m). Pub. L. 115–141 inserted “or on a State-Supported Amtrak route with a valid cost-sharing agreement under section 209 of the Passenger Rail Investment and Improvement Act of 2008 and no current nonattainment areas under subsection (d),” after “2012,”.

2015—Subsec. (b)(1)(A)(i)(I). Pub. L. 114–94, § 1114(1)(A), inserted “in the designated nonattainment area” after “air quality standard”.

Subsec. (b)(3). Pub. L. 114–94, § 1114(1)(B), inserted “or maintenance” after “likely to contribute to the attainment”.

Subsec. (b)(4). Pub. L. 114–94, § 1114(1)(C), substituted “attainment or maintenance in the area of” for “attainment of”.

Subsec. (b)(8)(A)(ii). Pub. L. 114–94, § 1114(1)(E)(i)(I), inserted “or port-related freight operations” after “construction projects” in introductory provisions.

Subsec. (b)(8)(A)(ii)(II). Pub. L. 114–94, § 1114(1)(E)(i)(II), inserted “or chapter 53 of title 49” after “this title”.

Subsec. (b)(9). Pub. L. 114–94, § 1114(1)(D), (E)(ii), (F), added par. (9).

Subsec. (c)(2). Pub. L. 114–94, § 1114(2), inserted “(giving priority to corridors designated under section 151)” after “at any location in the State”.

Subsec. (d)(1)(B). Pub. L. 114–94, § 1114(3)(A), amended subpar. (B) generally. Prior to amendment, subpar. (B) read as follows: “is eligible under the surface transportation program under section 133.”

Subsec. (d)(2)(A). Pub. L. 114–94, § 1114(3)(B)(i)(I), inserted “would otherwise be eligible under subsection (b) if the project were carried out in a nonattainment or maintenance area or” after “may use for any project that” in introductory provisions.

Pub. L. 114–94, § 1109(c)(5), substituted “surface transportation block grant program” for “surface transportation program” in introductory provisions.

Subsec. (d)(2)(A)(i). Pub. L. 114–94, § 1114(3)(B)(i)(II), substituted “subsection (k)(1)” for “paragraph (l)”.

Subsec. (d)(2)(B)(i). Pub. L. 114–94, § 1114(3)(B)(ii), substituted “MAP–21” for “MAP–21t”.

Subsec. (d)(3). Pub. L. 114–94, § 1114(3)(C), inserted “, in a manner consistent with the approach that was in effect on the day before the date of enactment of MAP–21,” after “the Secretary shall modify”.

Subsec. (g)(2)(B). Pub. L. 114–94, § 1114(4), substituted “not later than” for “not later that”.

Subsec. (k)(3), (4). Pub. L. 114–94, § 1114(5), added pars. (3) and (4).

Subsec. (l)(1)(B). Pub. L. 114–94, § 1114(6), inserted “air quality and traffic congestion” before “performance targets”.

Subsec. (m). Pub. L. 114–94, § 1114(7), substituted “section 104(b)(4)” for “section 104(b)(2)”.

2014—Subsec. (m). Pub. L. 113–76 substituted “for which CMAQ funding was made available, obligated or expended in fiscal year 2012, and shall have no imposed time limitation” for “that was previously eligible under this section”.

2012—Subsec. (b). Pub. L. 112–141, § 1113(a)(1), (5), in introductory provisions, substituted “in subsection (d)” for “in subsection (c)” and “section 104(b)(4)” for “section 104(b)(2)” and struck out concluding provisions which read as follows: “No funds may be provided under this section for a project which will result in the construction of new capacity available to single occupant vehicles unless the project consists of a high occupancy vehicle facility available to single occupant vehicles only at other than peak travel times. In areas of a State which are nonattainment for ozone or carbon monoxide, or both, and for PM–10 resulting from transportation activities, the State may obligate such funds for any project or program under paragraph (1) or (2) without regard to any limitation of the Department of Transportation relating to the type of ambient air quality standard such project or program addresses.”

Subsec. (b)(5). Pub. L. 112–141, § 1113(a)(2), inserted “add turning lanes,” after “improve intersections,” and substituted “paragraph, including programs or projects to improve incident and emergency response or improve mobility, such as through real-time traffic, transit, and multimodal traveler information;” for “paragraph;”.

Subsec. (b)(7). Pub. L. 112–141, § 1113(a)(3), (7), added par. (7). Former par. (7) redesignated (8).

Subsec. (b)(7)(A)(ii). Pub. L. 112–141, § 1113(a)(4), substituted “verified technologies (as defined in section 791 of the Energy Policy Act of 2005 (42 U.S.C. 16131))” for “published in the list under subsection (f)(2)” in introductory provisions.

Subsec. (b)(8). Pub. L. 112–141, § 1113(a)(6), redesignated par. (7) as (8).

Subsec. (c). Pub. L. 112–141, § 1113(b)(2), added subsec. (c). Former subsec. (c) redesignated (d).

Subsec. (d). Pub. L. 112–141, § 1113(b)(3), added subsec. (d) and struck out former subsec. (d) which related to states receiving minimum apportionment.

Pub. L. 112–141, § 1113(b)(1), redesignated subsec. (c) as (d). Former subsec. (d) redesignated (e).

Subsec. (e). Pub. L. 112–141, § 1113(b)(1), redesignated subsec. (d) as (e). Former subsec. (e) redesignated (f).

Subsec. (f). Pub. L. 112–141, § 1113(b)(1), (4), redesignated subsec. (e) as (f) and substituted “104(b)(4)” for “104(b)(2)” in par. (3). Former subsec. (f) redesignated (g).

Subsec. (g). Pub. L. 112–141, § 1113(b)(1), (5), redesignated subsec. (f) as (g), added par. (3), and struck out former par. (3) which related to priority. Former subsec. (g) redesignated (h).

Subsec. (h). Pub. L. 112–141, § 1113(b)(1), redesignated subsec. (g) as (h). Former subsec. (h) redesignated (i).

Subsec. (i). Pub. L. 112–141, § 1113(b)(6), added subsec. (i) and struck out former subsec. (i) which related to evaluation and assessment of projects.

Pub. L. 112–141, § 1113(b)(1), redesignated subsec. (h) as (i).

Subsecs. (j) to (m). Pub. L. 112–141, § 1113(b)(6), added subsecs. (j) to (m).

2005—Subsec. (b). Pub. L. 109–59, § 1808(a), inserted “or is required to prepare, and file with the Administrator of the Environmental Protection Agency, maintenance plans under the Clean Air Act (42 U.S.C. 7401 et seq.)” after “1997,” in introductory provisions.

Subsec. (b)(1). Pub. L. 109–59, § 1808(b)(1), added par. (1) and struck out former par. (1) which read as follows:

“(A) if the Secretary, after consultation with the Administrator of the Environmental Protection Agency, determines, on the basis of information published by the Environmental Protection Agency pursuant to section 108(f)(1)(A) of the Clean Air Act (other than clause (xvi) of such section), that the project or program is likely to contribute to—

“(i) the attainment of a national ambient air quality standard; or

“(ii) the maintenance of a national ambient air quality standard in a maintenance area; or

“(B) in any case in which such information is not available, if the Secretary, after such consultation, determines that the project or program is part of a program, method, or strategy described in such section;”.

Subsec. (b)(4). Pub. L. 109–59, § 1808(b)(2)(A), inserted “, including advanced truck stop electrification systems,” after “control facility or program”.

Subsec. (b)(5). Pub. L. 109–59, § 1808(b)(3)(A), inserted “improve transportation systems management and operations that mitigate congestion and improve air quality,” after “intersections,”.

Subsec. (b)(6), (7). Pub. L. 109–59, § 1808(b)(2)(B), (3)(B), (4), which directed addition of pars. (6) and (7) at end of subsec. (b), was executed by adding pars. (6) and (7) after par. (5) to reflect the probable intent of Congress.

Subsec. (c)(1). Pub. L. 109–59, § 1808(c)(1), substituted “for any project in the State that—” and subpars. (A) and (B) for “for any project eligible under the surface transportation program under section 133.”

Subsec. (c)(2). Pub. L. 109–59, § 1808(c)(2), substituted “for any project in the State that—” and subpars. (A) and (B) for “for any project in the State eligible under section 133.”

Subsecs. (f) to (h). Pub. L. 109–59, § 1808(d)–(f), added subsecs. (f) to (h).

1998—Subsec. (a). Pub. L. 105–178, § 1110(a), substituted “shall establish and implement” for “shall establish”.

Subsec. (b). Pub. L. 105–178, § 1110(b)(1), in introductory provisions, substituted “that is or was designated as a nonattainment area for ozone, carbon monoxide, or particulate matter under section 107(d) of the Clean Air Act (42 U.S.C. 7407(d)) and classified pursuant to section 181(a), 186(a), 188(a), or 188(b) of the Clean Air Act (42 U.S.C. 7511(a), 7512(a), 7513(a), or 7513(b)) or is or was designated as a nonattainment area under such section 107(d) after December 31, 1997,” for “that was designated as a nonattainment area under section 107(d) of the Clean Air Act (42 U.S.C. 7407(d)) during any part of fiscal year 1994”.

Subsec. (b)(1)(A). Pub. L. 105–178, § 1110(b)(2), substituted “clause (xvi) of such section” for “clauses (xii) and (xvi) of such section”.

Subsec. (b)(1)(A)(ii). Pub. L. 105–178, § 1110(b)(3), substituted “a maintenance area” for “an area that was designated as a nonattainment area but that was later redesignated by the Administrator of the Environmental Protection Agency as an attainment area under section 107(d) of the Clean Air Act (42 U.S.C. 7407(d))”.

Subsec. (b)(5). Pub. L. 105–178, § 1110(b)(4)–(6), added par. (5).

Subsec. (c). Pub. L. 105–178, § 1110(c), added subsec. (c) and struck out heading and text of former subsec. (c). Text read as follows: “If a State does not have a nonattainment area for ozone or carbon monoxide under the Clean Air Act located within its borders, the State may use funds apportioned to it under section 104(b)(2) for any project eligible for assistance under the surface transportation program.”

Subsec. (e). Pub. L. 105–178, § 1110(d)(1), added subsec. (e).

1995—Subsec. (b). Pub. L. 104–59, § 319(a)(1)(A), in introductory provisions, inserted “if the project or program is for an area in the State that was designated as a nonattainment area under section 107(d) of the Clean Air Act (42 U.S.C. 7407(d)) during any part of fiscal year 1994 and” after “project or program”.

Subsec. (b)(1)(A). Pub. L. 104–59, § 319(a)(1)(B), substituted “contribute to—” and cls. (i) and (ii) for “contribute to the attainment of a national ambient air quality standard; or”.

Subsec. (b)(2). Pub. L. 104–59, § 319(b)(1), struck out “or” at end.

Subsec. (b)(3). Pub. L. 104–88, § 405(b)(1), inserted “or” after semicolon at end.

Pub. L. 104–59, § 319(b)(2), substituted a semicolon for period at end.

Subsec. (b)(4). Pub. L. 104–88, § 405(b)(2), substituted a period for “; or” at end.

Pub. L. 104–59, § 319(b)(3), as amended by Pub. L. 104–88, § 405(a)(2), added par. (4).

1992—Subsec. (b). Pub. L. 102–388 inserted at end “In areas of a State which are nonattainment for ozone or carbon monoxide, or both, and for PM–10 resulting from transportation activities, the State may obligate such funds for any project or program under paragraph (1) or (2) without regard to any limitation of the Department of Transportation relating to the type of ambient air quality standard such project or program addresses.”

1991—Pub. L. 102–240 substituted section catchline for one which read: “Truck lanes” and amended text generally. Prior to amendment, text read as follows: “The Secretary may approve as a project on any Federal-aid system the construction of exclusive or preferential truck lanes.”

### Statutory Notes and Related Subsidiaries

### Effective Date of 2021 Amendment

Amendment by Pub. L. 117–58 effective Oct. 1, 2021, see section 10003 of Pub. L. 117–58, set out as a note under section 101 of this title.

### Effective Date of 2015 Amendment

Amendment by Pub. L. 114–94 effective Oct. 1, 2015, see section 1003 of Pub. L. 114–94, set out as a note under section 5313 of Title 5, Government Organization and Employees.

### Effective Date of 2012 Amendment

Amendment by Pub. L. 112–141 effective Oct. 1, 2012, see section 3(a) of Pub. L. 112–141, set out as an Effective and Termination Dates of 2012 Amendment note under section 101 of this title.

### Effective Date of 1995 Amendment

Amendment by section 405(b) of Pub. L. 104–88 effective Jan. 1, 1996, see section 2 of Pub. L. 104–88, set out as an Effective Date note under section 1301 of Title 49, Transportation.

Pub. L. 104–88, title IV, § 405(a), Dec. 29, 1995, 109 Stat. 956, provided that the amendment made by section 405(a)(2) is effective Nov. 28, 1995.

### Effective Date of 1991 Amendment

Amendment by Pub. L. 102–240 effective Dec. 18, 1991, and applicable to funds authorized to be appropriated or made available after Sept. 30, 1991, and, with certain exceptions, not applicable to funds appropriated or made available on or before Sept. 30, 1991, see section 1100 of Pub. L. 102–240, set out as a note under section 104 of this title.

### Reduction of Truck Emissions at Port Facilities

Pub. L. 117–58, div. A, title I, § 11402, Nov. 15, 2021, 135 Stat. 553, provided that:Establishment of Program.— In general.—The Secretary [of Transportation] shall establish a program to reduce idling at port facilities, under which the Secretary shall— study how ports and intermodal port transfer facilities would benefit from increased opportunities to reduce emissions at ports, including through the electrification of port operations; study emerging technologies and strategies that may help reduce port-related emissions from idling trucks; and coordinate and provide funding to test, evaluate, and deploy projects that reduce port-related emissions from idling trucks, including through the advancement of port electrification and improvements in efficiency, focusing on port operations, including heavy-duty commercial vehicles, and other related projects. Consultation.—In carrying out the program under this subsection, the Secretary may consult with the Secretary of Energy and the Administrator of the Environmental Protection Agency.Grants.— In general.—In carrying out subsection (a)(1)(C), the Secretary shall award grants to fund projects that reduce emissions at ports, including through the advancement of port electrification. Cost share.—A grant awarded under paragraph (1) shall not exceed 80 percent of the total cost of the project funded by the grant. Coordination.—In carrying out the grant program under this subsection, the Secretary shall— to the maximum extent practicable, leverage existing resources and programs of the Department [of Transportation] and other relevant Federal agencies; and coordinate with other Federal agencies, as the Secretary determines to be appropriate.Application; selection.— Application.—The Secretary shall solicit applications for grants under paragraph (1) at such time, in such manner, and containing such information as the Secretary determines to be necessary. Selection.—The Secretary shall make grants under paragraph (1) by not later than April 1 of each fiscal year for which funding is made available. Requirement.—Notwithstanding any other provision of law, any project funded by a grant under this subsection shall be treated as a project on a Federal-aid highway under chapter 1 of title 23, United States Code. Report.—Not later than 1 year after the date on which all of the projects funded with a grant under subsection (b) are completed, the Secretary shall submit to Congress a report that includes— the findings of the studies described in subparagraphs (A) and (B) of subsection (a)(1); the results of the projects that received a grant under subsection (b); any recommendations for workforce development and training opportunities with respect to port electrification; and any policy recommendations based on the findings and results described in paragraphs (1) and (2).”

### Healthy Streets Program

Pub. L. 117–58, div. A, title I, § 11406, Nov. 15, 2021, 135 Stat. 575, provided that: Definitions.—In this section: Cool pavement.—The term ‘cool pavement’ means a pavement with reflective surfaces with higher albedo to decrease the surface temperature of that pavement. Eligible entity.—The term ‘eligible entity’ means— a State; a metropolitan planning organization; a unit of local government; a Tribal government; and a nonprofit organization working in coordination with an entity described in subparagraphs (A) through (D). Low-income community.—The term ‘low-income community’ means a census block group in which not less than 30 percent of the population lives below the poverty line (as defined in section 673 of the Community Services Block Grant Act (42 U.S.C. 9902)). Porous pavement.—The term ‘porous pavement’ means a paved surface with a higher than normal percentage of air voids to allow water to pass through the surface and infiltrate into the subsoil. Program.—The term ‘program’ means the Healthy Streets program established under subsection (b). State.—The term ‘State’ has the meaning given the term in section 101(a) of title 23, United States Code. Tribal government.—The term ‘Tribal government’ means the recognized governing body of any Indian or Alaska Native tribe, band, nation, pueblo, village, community, component band, or component reservation, individually identified (including parenthetically) in the list published most recently as of the date of enactment of this Act [Nov. 15, 2021] pursuant to section 104 of the Federally Recognized Indian Tribe List Act of 1994 (25 U.S.C. 5131). Establishment.—The Secretary [of Transportation] shall establish a discretionary grant program, to be known as the ‘Healthy Streets program’, to provide grants to eligible entities— to deploy cool pavements and porous pavements; and to expand tree cover. Goals.—The goals of the program are— to mitigate urban heat islands; to improve air quality; and to reduce— the extent of impervious surfaces; stormwater runoff and flood risks; and heat impacts to infrastructure and road users.Application.— In general.—To be eligible to receive a grant under the program, an eligible entity shall submit to the Secretary an application at such time, in such manner, and containing such information as the Secretary may require. Requirements.—The application submitted by an eligible entity under paragraph (1) shall include a description of— how the eligible entity would use the grant funds; and the contribution that the projects intended to be carried out with grant funds would make to improving the safety, health outcomes, natural environment, and quality of life in low-income communities and disadvantaged communities. Use of Funds.—An eligible entity that receives a grant under the program may use the grant funds for 1 or more of the following activities: Conducting an assessment of urban heat islands to identify hot spot areas of extreme heat or elevated air pollution. Conducting a comprehensive tree canopy assessment, which shall assess the current tree locations and canopy, including— an inventory of the location, species, condition, and health of existing tree canopies and trees on public facilities; and an identification of— the locations where trees need to be replaced; empty tree boxes or other locations where trees could be added; and flood-prone locations where trees or other natural infrastructure could mitigate flooding. Conducting an equity assessment by mapping tree canopy gaps, flood-prone locations, and urban heat island hot spots as compared to— pedestrian walkways and public transportation stop locations; low-income communities; and disadvantaged communities. Planning activities, including developing an investment plan based on the results of the assessments carried out under paragraphs (1), (2), and (3). Purchasing and deploying cool pavements to mitigate urban heat island hot spots. Purchasing and deploying porous pavement to mitigate flooding and stormwater runoff in— pedestrian-only areas; and areas of low-volume, low-speed vehicular use. Purchasing of trees, site preparation, planting of trees, ongoing maintenance and monitoring of trees, and repairing of storm damage to trees, with priority given to— to the extent practicable, the planting of native species; and projects located in a neighborhood with lower tree cover or higher maximum daytime summer temperatures compared to surrounding neighborhoods. Assessing underground infrastructure and coordinating with local transportation and utility providers. Hiring staff to conduct any of the activities described in paragraphs (1) through (8). Priority.—In awarding grants to eligible entities under the program, the Secretary shall give priority to an eligible entity— proposing to carry out an activity or project in a low-income community or a disadvantaged community; that has entered into a community benefits agreement with representatives of the community; or that is partnering with a qualified youth or conservation corps (as defined in section 203 of the Public Lands Corps Act of 1993 (16 U.S.C. 1722)). Distribution Requirement.—Of the amounts made available to carry out the program for each fiscal year, not less than 80 percent shall be provided for projects in urbanized areas (as defined in section 101(a) of title 23, United States Code).Federal Share.— In general.—Except as provided under paragraph (2), the Federal share of the cost of a project carried out under the program shall be 80 percent. Waiver.—The Secretary may increase the Federal share requirement under paragraph (1) to 100 percent for projects carried out by an eligible entity that demonstrates economic hardship, as determined by the Secretary. Maximum Grant Amount.—An individual grant under this section shall not exceed $15,000,000. Treatment of Projects.—Notwithstanding any other provision of law, a project assisted under this section shall be treated as a project on a Federal-aid highway under chapter 1 of title 23, United States Code.”

### Determination by Secretary; Water-Phased Hydrocarbon Fuel Emulsion Technologies

Pub. L. 105–178, title I, § 1110(d)(2), June 9, 1998, 112 Stat. 144, as amended by Pub. L. 105–206, title IX, § 9002(g), July 22, 1998, 112 Stat. 836, provided that: “For the purposes of section 149(e) [now 149(f)] of title 23, United States Code, the Secretary shall determine in accordance with the procedures specified in section 149(b) of such title whether water-phased hydrocarbon fuel emulsion technologies that consist of a hydrocarbon base and water in an amount not less than 20 percent by volume reduce emissions of hydrocarbon, particulate matter, carbon monoxide, or nitrogen oxide from motor vehicles.”

### Study of CMAQ Program

Pub. L. 105–178, title I, § 1110(e), June 9, 1998, 112 Stat. 144, provided that: In general.—The Secretary and the Administrator of the Environmental Protection Agency shall enter into arrangements with the National Academy of Sciences to complete, by not later than January 1, 2001, a study of the congestion mitigation and air quality improvement program under section 149 of title 23, United States Code. The study shall, at a minimum— evaluate the air quality impacts of emissions from motor vehicles; evaluate the negative effects of traffic congestion, including the economic effects of time lost due to congestion; determine the amount of funds obligated under the program and make a comprehensive analysis of the types of projects funded under the program; evaluate the emissions reductions attributable to projects of various types that have been funded under the program; assess the effectiveness, including the quantitative and nonquantitative benefits, of projects funded under the program and include, in the assessment, an estimate of the cost per ton of pollution reduction; assess the cost effectiveness of projects funded under the program with respect to congestion mitigation; compare— the costs of achieving the air pollutant emissions reductions achieved under the program; to the costs that would be incurred if similar reductions were achieved by other measures, including pollution controls on stationary sources; include recommendations on improvements, including other types of projects, that will increase the overall effectiveness of the program; include recommendations on expanding the scope of the program to address traffic-related pollutants that, as of the date of the study, are not addressed by the program. Report.—Not later than January 1, 2000, the National Academy of Sciences shall transmit to the Secretary, the Committee on Transportation and Infrastructure and the Committee on Commerce of the House of Representatives, and the Committee on Environment and Public Works of the Senate a report on the results of the study with recommendations for modifications to the congestion mitigation and air quality improvement program in light of the results of the study. Funding.—Before making the apportionment of funds under [former] section 104(b)(2) of title 23, United States Code, for each of fiscal years 1999 and 2000, the Secretary shall deduct from the amount to be apportioned under such section for such fiscal year, and make available, $500,000 for such fiscal year to carry out this subsection.”

### Effect of Limitation on Apportionment

Notwithstanding any other provision of law, for each of fiscal years 1996 and 1997, amendment by section 319(a)(1) of Pub. L. 104–59 not to affect any apportionment adjustments under section 1015 of the Intermodal Surface Transportation Efficiency Act of 1991, Pub. L. 102–240, see section 319(c) of Pub. L. 104–59, set out as a note under section 104 of this title.

### Value Pricing Pilot Program

Pub. L. 102–240, title I, § 1012(b), Dec. 18, 1991, 105 Stat. 1938, as amended by Pub. L. 104–59, title III, § 325(e), Nov. 28, 1995, 109 Stat. 592; Pub. L. 105–178, title I, § 1216(a), June 9, 1998, 112 Stat. 211; Pub. L. 105–206, title IX, § 9006(b), July 22, 1998, 112 Stat. 848; Pub. L. 109–59, title I, § 1604(a), Aug. 10, 2005, 119 Stat. 1249, provided that: The Secretary shall solicit the participation of State and local governments and public authorities for one or more value pricing pilot programs. The Secretary may enter into cooperative agreements with as many as 15 such State or local governments or public authorities to establish, maintain, and monitor value pricing programs. Notwithstanding section 129 of title 23, United States Code, the Federal share payable for such programs shall be 80 percent. The Secretary shall fund all preimplementation costs and project design, and all of the development and other start up costs of such projects, including salaries and expenses, for a period of at least 1 year, and thereafter until such time that sufficient revenues are being generated by the program to fund its operating costs without Federal participation, except that the Secretary may not fund the preimplementation or implementation costs of any project for more than 3 years. Revenues generated by any pilot project under this subsection must be applied to projects eligible under such title. Notwithstanding sections 129 and 301 of title 23, United States Code, the Secretary shall allow the use of tolls on the Interstate System as part of any value pricing pilot program under this subsection. The Secretary shall monitor the effect of such programs for a period of at least 10 years, and shall report to the Committee on Environment and Public Works of the Senate and the Committee on Transportation and Infrastructure of the House of Representatives every 2 years on the effects such programs are having on driver behavior, traffic volume, transit ridership, air quality, and availability of funds for transportation programs. HOV passenger requirements.—Notwithstanding section 102(a) of title 23, United States Code, a State may permit vehicles with fewer than 2 occupants to operate in high occupancy vehicle lanes if the vehicles are part of a value pricing pilot program under this subsection. Financial effects on low-income drivers.—Any value pricing pilot program under this subsection shall include, if appropriate, an analysis of the potential effects of the pilot program on low-income drivers and may include mitigation measures to deal with any potential adverse financial effects on low-income drivers.Funding.— In general.—There are authorized to be appropriated to the Secretary from the Highway Trust Fund (other than the Mass Transit Account) to carry out this subsection— for fiscal year 2005, $11,000,000; and for each of fiscal years 2006 through 2009, $12,000,000. Set-aside for projects not involving highway tolls.—Of the amounts made available to carry out this subsection, $3,000,000 for each of fiscal years 2006 through 2009 shall be available only for congestion pricing pilot projects that do not involve highway tolls. Availability.—Funds allocated by the Secretary to a State under this subsection shall remain available for obligation by the State for a period of 3 years after the last day of the fiscal year for which the funds are authorized. Use of unallocated funds.—If the total amount of funds made available from the Highway Trust Fund to carry out this subsection for fiscal year 1998 and fiscal years thereafter but not allocated exceeds $8,000,000 as of September 30 of any year, the excess amount— shall be apportioned in the following fiscal year by the Secretary to all States in accordance with [former] section 104(b)(3) of title 23, United States Code; shall be considered to be a sum made available for expenditure on the surface transportation program, except that the amount shall not be subject to section 133(d) of such title; and shall be available for any purpose eligible for funding under section 133 of such title. [probably should be (E)] Contract authority.—Funds authorized to carry out this subsection shall be available for obligation in the same manner as if the funds were apportioned under chapter 1 of title 23, United States Code; except that the Federal share of the cost of any project under this subsection and the availability of funds authorized to carry out this subsection shall be determined in accordance with this subsection.”