When the route of a railroad company shall have been determined, a survey of the route and location, particularly describing the same, shall be filed in the office of the secretary of state.
The company may also from time to time after the filing of the survey of the route of the main line, and either before or after construction thereon, file surveys of the route and location of branches within the limits of any counties in or through which the main line may be located and of any county adjoining such counties.