Whenever a petition is received by the board having jurisdiction, requiring a new road to be laid out, said board, when in its judgment circumstances warrant the same, shall employ a competent surveyor to survey and lay out said road, and such survey must include a line of levels to be run over the laid out road and a grade line to be established thereon, such grade line not to be greater than ten percent when completed. In laying out said road the board may deviate or depart, or may direct a deviation or departure, from the road described in the petition when it is practicable and less expensive to do so in order to obtain a grade line not exceeding ten percent. Such surveyor shall prepare a plan and profile of the surveyor’s survey and shall file a copy of the same with the township clerk or the county auditor, as the case may be, and the board having jurisdiction shall require that such road, when completed, must conform to the plan and profile of the surveyor as filed with the township clerk or county auditor.