In Kyrene School District No. 28 v. City of Chandler, 150 Ariz. 240, 243, 722 P.2d 967, 970 (App. 1986), the City of Chandler imposed system development charges on new buildings based on the size of the meter installed in the building. Id. at 242, 722 P.2d at 969. The resulting funds were deposited in the City's "water development reserve fund" to be used for later expansion and enlargement of the water system in Chandler. Id. The school district argued that the charge was a tax and, therefore, invalid. Id. Nevertheless, applying the test set forth in Stewart, the Court concluded that "system development charges" imposed by the City of Chandler were fees, not taxes. Id. The Court explained that the school district "received the overall benefit of Chandler's water and wastewater systems in exchange for the system development charges." Id. at 243, 722 P.2d at 970. Thus, the amount charged the school district was based on the cost of the systems providing the service and, unlike a tax, the charges were not "based on an ability to pay theory." Id. Moreover, although the funds were used for "the general governmental purpose of providing citywide water and sewer service," the fees charged "represented part of the capital cost of the wastewater and water systems spread among its users." Id. at 244, 722 P.2d at 971. Thus, the Court concluded, the charges were appropriately considered fees, not taxes. Id.