If the county board shall find for the improvement, it shall cause to be entered on its journal an order directing the county surveyor, or an engineer, to go upon the line described in the petition, or as changed by the board in accordance with section 31-106 ; to survey and level the same and set a stake at every hundred feet, numbering downstream; to note the intersection of section lines, road crossings, boundary lines, precinct and county lines; to make a report, profile and plat of the same; and to estimate the number of cubic yards for each working section as hereinafter provided.