(1) Prior to the effective date of the proposed rates or charges, a petition may be filed with the commission requesting a review of the proposed rates and charges. The petition shall be signed by at least twenty-five percent of the private water company's customers. Upon receipt of a petition, the commission shall set a time, place, and date for a public hearing to consider the proposed rates or charges. The hearing shall be held within ninety days after the filing of the petition pursuant to the rules and regulations of the commission.

(2) Notice of a hearing shall be served on customers by the commission at least fifteen days prior to the day of the hearing. Notice of the hearing shall also be published by the commission at least once a week for two successive weeks in a newspaper of general circulation in each service area affected by or to be affected by the proposed rates or charges with the date of last publication at least ten days prior to the hearing.

(3) At least ten days prior to the hearing, the commission shall make all files and information gathered by it and its employees and agents relating to the matter to be heard available for inspection during regular office hours.

(4) Any person may appear at the hearing and present testimony, evidence, exhibits, or other information and may do so in person or by counsel, or both, pursuant to the rules and regulations of the commission.