If any city of the first class avails itself of the provisions of this act, there shall be attached to the department of public works of such city a bureau of zoning, under the direction of a chief of said bureau, and with such other officials, clerks and employes as the council may determine. All ordinances passed under the provisions of this act shall be enforced by the bureau of zoning, subject to the right of appeal to the board of adjustment, and to the courts as herein provided for.