The City Council may, from time to time, on its own motion, or on petition, or on recommendation from the Planning Commission, amend the regulations and districts established under this chapter after public notice and hearing in each case. All proposed amendments of the regulations or districts herein established shall be filed in writing in a form required by the City Council.

Every proposed amendment, unless initiated by the Planning Commission, shall be referred to the Planning Commission. The Planning Commission shall report in writing its recommendations thereon to the City Council, accompanied by a full statement of the reasons for such recommendations, prior to the public hearing. If the Planning Commission fails to report within a period of 90 days from the date of receipt of notice or such longer time as may have been agreed upon by it and the City Council, the City Council may act without such report. If the Planning Commission recommends disapproval of the proposed amendment, or recommends modification thereof, the City Council shall not act contrary to such disapproval or recommendation except by the adoption of a resolution fully setting forth the reasons for such contrary action.

Wherever the owners of 50% or more of the frontage in any district or part thereof shall present a petition duly signed and acknowledged to the City Council requesting an amendment, supplement, change or repeal of the regulations prescribed for such district or part thereof, it shall be the duty of the Council to vote upon said petition within 90 days after filing of the same by the petitioners with the City Clerk.

The City Council, by resolution, shall fix the time and place of the public hearing and cause notice to be given as follows:

If a protest against the proposed amendment is presented to the City Council, duly signed and acknowledged by the owners of 20% or more of the area of land included in such proposed amendment, or by the owners of 20% or more of the area of land immediately adjacent extending 100 feet therefrom, or by the owners of 20% or more of the area of land directly opposite thereto extending 100 feet from the street frontage of such opposite land, such amendment shall not be passed except by the favorable vote of at least a 3/4 majority of the City Council.

The City Council shall set the public hearing as required and shall render its decision within 120 days of the receipt of the Planning Commission's report. If the City Council deems it advisable, it may require, as a condition for approval of the amendment, that the amended area be put to use within a reasonable length of time.

The City Council shall notify the applicant for an amendment of its decision in writing within five days after the decision has been rendered.