1. Short title This Act may be cited as the Transportation Megaprojects Accountability and Oversight Act of 2018 . 2. Additional requirements for certain transportation projects (a) In general Section 106 of title 23, United States Code, is amended by adding at the end the following: (k) Megaprojects (1) Megaproject defined In this subsection, the term megaproject means a project that has an estimated total cost of $2,500,000,000 or more, and such other projects as may be identified by the Secretary. (2) Comprehensive risk management plan A recipient of Federal financial assistance under this title for a megaproject shall, in order to be authorized for construction, submit to the Secretary a comprehensive risk management plan that contains— (A) a description of the process by which the recipient will identify, quantify, and monitor the risks that might result in cost overruns, project delays, reduced construction quality, or reductions in benefits with respect to the megaproject; (B) examples of mechanisms the recipient will use to track risks identified pursuant to subparagraph (A); (C) a plan to control such risks; and (D) such assurances as the Secretary considers appropriate that the recipient will, with respect to the megaproject— (i) regularly submit to the Secretary updated cost estimates