Officers and employees of city and state agencies may be transferred to the authority or water board and officers and employees of the authority or water board may be transferred to appropriate city and state agencies without examination and without loss of any civil service or retirement status or rights. Any officer or employee of the authority or water board who heretofore acquired or shall hereafter acquire such position status by transfer and who at the time of such transfer was a member of the New York city employees’ retirement system shall continue to be a member of such system as long as he or she continues in such service, and shall continue to have all the rights, privileges and obligations of membership in such system. Employment by the authority or water board shall constitute city-service for the purposes of chapter one of title thirteen of the administrative code of the city of New York. Transfers shall be in accordance with Civil Service Law § 70 (Transfers)section seventy of the civil service law or the rules of the civil service commission of the city, as the case may be. No such transfer shall be made except with the approval of the head of the agency involved, the director of the division of the budget or the director of management and budget of the city, as the case may be, and the chairman of the authority or water board, as applicable, and in compliance with the rules and regulations of the civil service commission of the city or the state, as the case may be.