(a) In this section, " sole expense" means the actual cost of relocating, raising, lowering, rerouting, changing the grade of, or altering the construction of a facility described in Subsection (b) in providing comparable replacement without enhancement of the facility, after deducting from that cost the net salvage value of the old facility.
(b) If the district, in the exercise of the power of eminent domain or relocation or another power granted under this chapter, makes necessary the relocating, raising, rerouting, changing the grade of, or altering the construction of a highway, a railroad, an electric transmission line, telephone or telegraph properties and facilities, or a pipeline, the necessary relocating, raising, rerouting, changing of grade, or alteration of construction shall be accomplished at the sole expense of the district.