This article shall apply only to conduits with a maximum flow capacity of 250 cubic feet per second or less of water, other than those conduits described in Section 5987.
If this section is for any reason held to be unconstitutional, such decision shall not affect the validity of Article 3 of this chapter and the Legislature hereby declares that the persons owning conduits referred to in this section shall be subject to the provisions of Article 3 of this chapter.