; (ii) a public transportation facility or service eligible for assistance under chapter 53 of title 49; or (iii) a facility or service for intercity rail passenger transportation (as defined in section 24102 of title 49). (D) System resilience A project for which a grant is provided under paragraph (3) or subparagraph (A), (B), or (C) of paragraph (4) may include the use of natural infrastructure or the construction or modification of storm surge, flood protection, or aquatic ecosystem restoration elements that the Secretary determines are functionally connected to a transportation improvement, such as— (i) increasing marsh health and total area adjacent to a highway right-of-way to promote additional flood storage; (ii) upgrades to and installation of culverts designed to withstand 100-year flood events; (iii) upgrades to and installation of tide gates to protect highways