(1) After the conclusion of any hearing held pursuant to section 75-1005 or 75-1007, the commission shall grant or deny the rates or charges that were considered at the hearing and, if other rates or charges are to be adopted, shall decide on any modifications to the rates or charges that the commission considers necessary based on the evidence adduced at the hearing.

(2) The commission shall issue a written order setting out its findings and reasoning for its decision. The commission's order may be appealed by a party to the proceeding. Such appeal shall be in accordance with section 75-136.

(3) If the hearing is held pursuant to a petition filed pursuant to section 75-1007, if the proposed rates or charges become effective before the decision of the commission, and if the decision denies the proposed rates or charges, then the proposed rates or charges shall be denied retroactively and any amounts collected under the proposed rates or charges shall be refunded by the private water company. If the hearing is held pursuant to a petition filed pursuant to section 75-1005 and if the decision of the commission modifies the established rates or charges, then the established rates or charges shall be modified as of the date of the decision and shall not be retroactive.