Breaking Down Barriers Act of 2011 - Authorizes the Secretary of Transportation (DOT) to include as part of a federal-aid highway project any activities carried out by a state before approval of its application for federal funding if such activities meet applicable project requirements.

Authorizes the Secretary, in order to accelerate project delivery, to issue a letter of no prejudice for a project at the time the project is included in the state transportation improvement program or as soon as practicable.

Revises and makes permanent the surface transportation project delivery pilot program.

Prohibits the Secretary from requiring a state, as a condition of participation in the program, to forego project delivery methods otherwise permissible for highway projects.

Authorizes a state to assume highway project responsibilities administered by the Federal Highway Administration (FHWA), but not the responsibilities of any other modal administration within the Department of Transportation (DOT).

Repeals the limitation to Alaska, California, Ohio, Oklahoma, and Texas of state participation in the program. Allows program participation by all states. Prescribes a special rule to permit a state participating in the program on September 30, 2009, to continue in the program and not be required to submit an application.

Directs the Comptroller General to study methods to consolidate and streamline the environmental impact statement process with respect to federal-aid highway and highway safety construction projects and public transportation projects, with particular focus on the feasibility of modernizing current procedures for environmental impact statements to include new media and other communication techniques.

Directs the Secretary to develop recommendations for expanding the list of activities categorically excluded from requirements for environmental assessments or environmental impact statements pursuant to regulations promulgated by the Council on Environmental Quality.

Authorizes the Secretary to enter into an agreement to permit a state to assume all of the Secretary's responsibilities for federal-aid highway and public transportation projects if the state certifies that: (1) the project will be carried out in accordance with applicable requirements, and (2) at least two-thirds of the total projects costs will be derived from state funds.

Directs the Secretary to extend the highway prompt payment program to other DOT transportation construction projects.

Directs the Secretary to issue regulations to establish deadlines for federal approval actions with respect to federal-aid highway and public transportation projects.

Authorizes the Secretary to approve a request by a state to provide state public transportation and federal-aid highway project funds to federal agencies (including the DOT), state agencies, and Indian tribes participating in the environmental review process for such projects, or in an approved state process, to support activities that extend beyond environmental work to other aspects and modes of program and project delivery.
Output: To amend titles 23 and 49, United States Code, to accelerate the delivery process for highway and public transportation construction projects, and for other purposes.