The city of Pocatello could be forced to pay back millions of dollars in excess fees following a recent Idaho Supreme Court ruling.

According to the unanimous opinion, justices ruled that Pocatello's sewer and water fees were not set at reasonable rates to help cover the costs of providing government services.

The city's sewer and water fees were first invalidated by a lower court in 2013. However, a separate party filed a new lawsuit in 2014 demanding a refund for being charged the illegal fee.

That lawsuit was dismissed in district court, but the Supreme Court said Wednesday the judge was wrong in deciding the city did not have to pay back the illegal fees. The lawsuit now goes back to the district court for proceedings consistent with the high court's decision.

Pocatello spokesman Logan McDougall declined to comment, but said the city is reviewing the decision.