Editor's note: The article has been updated to include comments from Janet Rummel, public relations and communications officer for the North Texas Municipal Water District.

The cities of Plano, Garland, Mesquite and Richardson have asked the Public Utility Commission of Texas to review the water rates with the North Texas Municipal Water District. The PUC will be seen as a third party.

Plano Mayor Harry LaRosiliere said the North Texas Water District structure ins inconsistent with conservation. Plano Mayor Harry LaRosiliere said the North Texas Water District structure ins inconsistent with conservation.[/caption]

“We took this action because the rates set by the water district under the six-decade-old water supply contract are discriminatory, are inconsistent with water conservation, and are not in the public['s] interest,” Plano City Manager Bruce Glasscock said during a Dec. 14 news conference at Garland City Hall.

Plano pays for 26.7 billion gallons of water annually, a rate that was set in 2001. Plano has not reached that usage level in a single year since 2006, Public Works Director Gerald Cosgrove said in a previous interview with Community Impact Newspaper.

The city of Plano has paid $78 million and the city of Richardson has paid $36 million for unused water over the last 15 years. The city of Mesquite has paid $36 million over the last 14 years and the city of Garland has paid $28 million over the last 10 years.

In total, the cities of Garland, Mesquite, Plano and Richardson have paid $178 million in unused water, according to information disseminated at the news conference.

“We are losing tens of millions of dollars at the expense of our taxpayers because the North Texas Municipal Water District’s prior rate methodology is outdated and does not incentivize water conservation,” Glasscock said.

Janet Rummel, the public relations and communications officer for the water district, said in an email the member cities are not just paying for water—used or unused—they are paying for the storage, pipes, treatment and testing of water and the investment in projects to make sure the district does not run out of water in the future.

"To divide the cost of the shared system among the cities, the 13 agreed by contract for each city’s portion to be based on its year of highest annual use," Rummel said. "NTWMD issued debt and built a system to meet that previous need. We must repay the debt and maintain those pipes regardless of how much water is used. Reducing the percent of the shared system costs paid by these four cites increases the percent paid by the other cities. All share the costs of the system, not just water used."

The four cities requesting this review are the four largest contributing NTMWD member cities, which pay more than 60 percent of the member city ratepayers. Other member cities include the cities of Allen, Frisco, McKinney, Farmersville, Forney, Princeton, Rockwall, Wylie and Royse City.

Representatives from the NTMWD's 13 member cities met in March to discuss how to explore possible amendments to the water contract, which was last amended in 1988. This group of representatives met at least five times in 2016, NTMWD spokesperson Janet Rummel said.

“While the 13 cities have not yet reached an agreement on a change, the district hasn’t given up seeking a potential solution,” NTMWD Executive Director Tom Kula said in a statement. “We believe the matter would be best resolved by the district working with the 13 member cities.”