(a) To the extent that a rule of the district conflicts with a rule of the regional water authority, the rule of the authority controls.
(b) To the extent that a rule of the district conflicts with an action of a municipally owned utility or water supply or sewer service corporation whose certificated area is located wholly or partly in the district's territory, the action of the utility or corporation controls.
(c) Notwithstanding Subsections (a) and (b), to the extent that a rule of the district concerning groundwater conflicts with a rule of the regional water authority or with an action of a municipally owned utility or water supply or sewer service corporation whose certificated area is located wholly or partly in the district's territory, the rule of the district controls.