Attorney General Mayes Challenges Massive Rate Hike for Robson Ranch Utility Customers

PHOENIX — Attorney General Kris Mayes yesterday filed an application for rehearing with the Arizona Corporation Commission, challenging a recent decision that approved dramatic water and sewer rate increases for residents of Robson Ranch, a retirement community south of Casa Grande.

The Commission voted 3-2 on March 4 to approve rate increases of nearly 23% for water service and a staggering 154% for sewer service — increases that will hit every residential customer in the community. Attorney General Mayes argues the decision violates the Commission's constitutional duty to set rates that are just and reasonable for both customers and shareholders.

"The Arizona Corporation Commission exists to protect ratepayers from exactly this kind of rate shock," said Attorney General Kris Mayes. "Approving a 154% sewer rate increase and a nearly 23% water rate increase while Commission staff openly admitted they never considered the impact on customers is a failure of the Commission's constitutional duty."

The filing argues the Commission made two critical errors. First, Commission staff witnesses testified under oath that they gave no consideration to the impact of the increases on ratepayers. One witness even stated that "Staff doesn't set rates based on affordability." Second, the Commission refused to obtain or review documents from the November 2024 sale of the utilities to a private equity-backed investment company, depriving itself of information relevant to setting a fair rate of return.

The utilities' previous owner, the homebuilder that developed Robson Ranch, held rates artificially low for 27 years, possibly to attract homebuyers with low utilities. However, months after a private equity firm acquired the utilities in November 2024, rates skyrocketed. Residents who bought homes with affordable utility costs in mind now face bills that bear no resemblance to what they planned for.

“Robson Ranch residents have no alternative utility providers, they are captive customers of Picacho Water Company and Picacho Sewer Company, with no ability to shop for better rates or switch to a competitor,” said Attorney General Mayes. “Arizona's founders enshrined the Corporation Commission in the state constitution specifically to protect consumers from exploitation by monopoly utilities. When the Commission fails to fulfill that role, my office will step in to protect Arizonans."

The filing asks the Commission to subpoena the purchase transaction documents and hold a full rehearing that weighs both customer impacts and shareholder interests as required by Arizona law.

A copy of the filing is available.