The commission is hereby authorized, whenever it is of opinion that the public interest so requires, to direct any public utility subject to the jurisdiction of the commission to award contracts or agreements for the construction, improvement or extension of its plant, works or system, exceeding in amount twenty-five thousand dollars in any calendar year, to the lowest responsible bidder, after a public offering has been made and after advertisement and notice of such offering have been given, and the commission may prescribe rules and regulations relative to such advertisement, notice and public letting.
New York Legal Code