California Code, Streets and Highways Code - SHC § 2450

(a) “Grade separation” means, for the purpose of calculating the railroad contribution to the project, the theoretical structure necessary to separate the roadway from the railroad grade for the number of lanes on the existing highway and for the full width of the railroad corridor, in accordance with the current design standards of the department.

(b) “Project” means the grade separation and other structures that actually separate the vehicular roadway from the railroad tracks, and all approaches, ramps, connections, drainage, and other construction required to make the grade separation operable and to effect the separation of grades.  A grade separation project may include provision for separation of nonmotorized traffic from the vehicular roadway and the railroad tracks.  If a separation of nonmotorized traffic is not to be included in a project, there shall be an affirmative finding that the separation of nonmotorized traffic is not in the public interest.  On any project where there is only one railroad track in existence, the project shall be built so as to provide for expansion to two tracks when the Director of Transportation determines that the project is on an existing or potential major railroad passenger corridor.  The project may consist of:

(c) “Highway” means city street, a county highway, or a state highway which is not a freeway as defined in Section 257.

(d) “Railroad” means a railroad corporation.