Section 90. Except as otherwise specifically provided in this chapter, it shall be the duty of the city manager to act as chief conservator of the peace within the city; to supervise the administration of the affairs of the city; to see that within the city the laws of the commonwealth and the ordinances, resolutions and regulations of the city council are faithfully executed; and to make such recommendations to the city council concerning the affairs of the city as may to him seem desirable; to make reports to the city council from time to time upon the affairs of the city; and to keep the city council fully advised of the city's financial condition and its future needs. He shall prepare and submit to the city council budgets as required of the mayor by section thirty-two of chapter forty-four and, in connection therewith, may, to the extent provided by said section thirty-two in the case of a mayor, require the submission to him, by all departments, commissions, boards and offices of the city, of estimates of the amounts necessary for their expenses. He shall make all appointments and removals in the departments, commissions, boards and offices of the city for whose administration he is responsible, except as otherwise provided in this chapter, and shall perform such other duties as may be prescribed by this chapter or be required of him by ordinance or resolution of the city council. The city manager shall have and possess, and shall exercise, all the powers, rights and duties, other than legislative, had, possessed or exercised, immediately prior to the adoption of this plan, by the mayor, board of aldermen, common council and all other boards, commissions and committees of the city and their members, severally or collectively, except such as are by this chapter conferred upon the school committee or are otherwise provided for thereby.