(a) This subchapter shall apply in cities of the first class to any water, electric light, or power improvement district organized under the laws of this state, whether general or special, and operated by a governing improvement board of commissioners or directors elected by the vote of the property owners owning real property within the municipal improvement district.
(b) This subchapter shall likewise apply to such districts even when they may have been consolidated with each other or when a water district and a light district shall have been consolidated with a sewer district, though in the latter case the property owned by the sewer district or sewer department, as the case may be, shall not be subject to the terms of this subchapter.