Sec. 4. EXCLUSIVENESS OF PROVISIONS. Only the provisions of this Act and of Articles 1667, 1672, and 1673 of the Revised Civil Statutes of Texas of 1925, shall apply in counties having a population of not less than eighty-three thousand (83,000), and not more than eighty-three thousand, three hundred and fifty (83,350), according to the last preceding Federal Census, which contain Navigation Districts, Water Improvement Districts, and Water Control and Improvement Districts.
Sec. 5. PARTIAL INVALIDITY. If any provision of this Act is held to be unconstitutional, or otherwise invalid, same shall not affect the validity of any other provision hereof.