On or before the tenth legislative day of each regular session of the Legislature, the authority shall make a report of its activities for the preceding calendar year to the Legislature. Each report shall set forth a complete operating and financial statement covering its operations during the year and shall contain a complete report of the engineers of the authority as to the physical condition of any project and shall include any recommendations made by such engineers. The authority shall cause an audit of its books and accounts to be made at least once in each year by certified public accountants and the cost thereof may be treated as a part of the cost of construction or of operation of the project.