Whenever the governing body of a municipality shall deem it necessary to open, lay out, widen, or enlarge any street, alley, or public place within the municipality, it shall cause an accurate survey and plat to be made by the city engineer, county surveyor, or other competent civil engineer, with an estimate of the probable cost of the improvement. Such engineer or surveyor shall file the survey, plat, and estimate in the office of the city auditor and shall retain an office copy.