Ariz. Rev. Stat. § 48-261
A. A fire district, community park maintenance district, sanitary district or hospital district for either a hospital or an urgent care center shall be created by the following procedures:
1. Any adult person desiring to propose creation of a district shall provide a legal description of the area proposed for inclusion in the district to the county assessor of the county in which the district is to be located. The county assessor shall provide to the person proposing formation of the district a detailed list of all taxable real and personal properties in the area proposed for inclusion in the district. The person proposing formation of the district shall prepare and submit a district impact statement to the board of supervisors of the county in which the district is to be located. The county assessor's parcel map and the assessed valuation of the properties as prescribed by section 42-17052 and as shown in the county assessor's records at the time the district impact statement is submitted are deemed sufficient for any required maps and for determining the assessed valuations prescribed by this section. Except for a proposed community park maintenance district that is to be located in more than one county, if a proposed district is located in more than one county, the impact statement shall be submitted to the board of supervisors of the county in which the majority of the total assessed valuation of the proposed district is located. The boards of supervisors of any other counties in which a portion of the district is to be located shall provide information and assistance to the responsible board of supervisors. For a community park maintenance district that is to be located in more than one county, the impact statement shall be submitted to the board of supervisors for each of the affected counties. If the person desiring to create a district pursuant to this section is unable to complete the district impact statement, the board of supervisors may assist in the completion of the impact statement if requested to do so, provided the bond required in subsection C of this section is in an amount sufficient to cover any additional cost to the county. The district impact statement shall contain at least the following information:
7. The petitions presented pursuant to paragraph 6 of this subsection shall comply with the provisions regarding verification in section 48-266 and shall:
B. For the purpose of determining the validity of the petitions presented pursuant to subsection A, paragraph 6 of this section:
1. Real or personal property held in multiple ownership shall be treated as if it had only one property owner, and the signature of only one of the owners of property held in multiple ownership is required on the formation petition. The number of persons owning property inside the boundaries of the proposed district shall be determined as follows:
2. The value of real or personal property shall be determined as follows: