All leases and concessions shall be in writing and shall be authorized by the city council. Each lease shall be subject to the general rules and regulations of the airport, except as the same may be excluded specifically by the particular lease. The city manager is empowered to adopt rules and regulations for the proper conduct and administration of the municipal airport and may perform or cause to be performed such other acts with reference to the management of said airport as are lawful and as may be expedient to promote the usefulness, convenience and public welfare. No improvements shall be constructed or building permits issued except with the approval of the city manager. All rules and regulations shall be in writing and shall be submitted to the council for their approval at least 10 days prior to the effective date. (Ord. 195 § 2, 1976)