Whenever any conduit for conducting water crosses a highway and no written records exist showing that the highway rights-of-way existed prior to the conduit rights-of-way, it shall be conclusively presumed that the conduit was in place and lawfully maintained prior to the highway and such conduit shall be repaired, improved for the benefit of the public agency having jurisdiction over such highway, and replaced, if necessary, by the public agency having jurisdiction over such highway, provided that usual acts of maintenance of the conduit, such as cleaning the conduit of dirt or silt, shall be performed by and at the expense of the person using the conduit.

This section shall not apply to any conduit as to which Section 7034 is applicable.