(1) The board of county commissioners shall be ex officio commissioners of the metropolitan sanitary and/or storm sewer district formed under the provisions of this part and shall have sole and complete jurisdiction over all drainage structures and sewage treating plants which are now or may be hereafter built and situated within said district. The commission shall be responsible for the proper functioning and maintenance thereof.
(2) The commission shall be responsible for the condition and maintenance of all publicly owned streets, alleys, land, parks, or other thoroughfares within the boundaries of such district insofar as such may be affected by the construction or maintenance of the structures under control and jurisdiction of such district.