Said board shall make and file with the city council of said city at least annually a detailed statement, duly certified by the president and secretary of said board under its seal, of the taxes received and placed to its credit during the preceding year, of all revenues received, and likewise of all disbursements made by said board in the operation and management of its facilities. The board shall also, at least annually, make a report to the council of the condition of the works under their charge, with a general summary of receipts and disbursements.