The district may levy, and collect or cause to be collected, taxes for any lawful purpose subject to a maximum limit of five cents ($0.05) per one hundred dollars ($100) of assessed value of all real estate and personal property; provided however, the district shall have the further power to levy, collect or cause to be collected, said property taxes to a maximum limit of ten cents ($0.10) if approval is first obtained from the City Council of the City of Stockton and the Board of Supervisors of the County of San Joaquin.