Title 48 of the Arizona Revised Statutes (ARS) gives the City Council the authority to order public improvements for streets, sidewalks, curbs, gutters, culverts, waterworks, sewers, storm water drainage, etc. The statutes do not require any petition process or request from the public to initiate the public improvements. Specifically ARS 48-572 reads:
48-572. Purposes for which public improvements may be undertaken; powers incidental to public improvements
A. When the public interest or convenience requires, the governing body of a municipality may:
1. Order the whole or any portion, either in length or width, of one or more of the streets of the municipality graded or regraded, paved or repaved, or otherwise improved or re-improved.
2. Order the construction, reconstruction or repair of any tunnel, subway, viaduct or conduit in, on, under or over any street, or land of the municipality or any land on, under or over which the municipality may have an easement or right-of-way therefore.
3. Order the construction or reconstruction of sidewalks, crosswalks, curbs, gutters, culverts, bridges, tunnels, siphons, manholes, steps, parkings and parkways and also pipes, hydrants and appliances for fire protection.
4. Order construction, reconstruction or acquisition of sewers, ditches, drains, conduits, pipelines and channels for sanitary and drainage purposes, or either or both thereof, with outlets, cesspools, manholes, catch basins, flush tanks, septic tanks, connecting sewers, ditches, drains, conduits, channels and other appurtenances in, under, over or through any street, or any land of the municipality or any right-of-way granted or obtained for such purpose, either within or without the limits of the municipality.
5. Order construction, reconstruction or acquisition of waterworks, ditches, canals, channels, conduits, pipelines and siphons, together with the necessary or usual appurtenances for carrying storm water or water from irrigation ditches, watercourses, streams or springs into, through or out of the municipality, in, under, over or through any street, or any land of the municipality or any right-of-way granted or obtained for such purpose, either within or without the limits of the municipality.
6. Order construction, reconstruction or acquisition of breakwater levees or walls, docks, wharves, marinas, boat harbors and related facilities.
7. Order construction, reconstruction or acquisition of lighting plants and poles, wires, conduits, lamps, standards and other appliances for the purpose of lighting and beautifying the streets improved.
8. Order the whole or any portion of any off-street parking area and entrances thereto of the municipality graded or regraded, paved or repaved, or otherwise improved or re-improved, order lighting plants and poles, wires, conduits, lamps, standards, and other appliances for the purpose of lighting, landscaping and beautifying the streets or off-street parking areas and entrances thereto to be improved and order construction on such land of parking structures that may have any portion at, above or below grade. If in connection with any lot or parcel within a proposed assessment district adequate off-street parking facilities have been provided, such lot or parcel shall be excluded from the assessment district and shall not be assessed for such improvements if within the time and in the manner provided in section 48-579, subsection C the owner or owners file a written objection to the extent of the assessment district. For purposes of this paragraph in cities having a zoning code or ordinance, unless the off-street parking facilities provided meet or exceed the requirements of the zoning code or ordinance for a lot or parcel of that size in that zone, then such off-street parking facilities shall not be deemed adequate. In cities not having a zoning code or ordinance, the facilities provided shall not be deemed adequate unless parking space for one motor vehicle is provided for each three hundred square feet of floor space in the building served by such off-street parking site. If any lot or parcel within a proposed assessment district organized for improvements provided for in this paragraph is zoned and used exclusively for single family residential purposes, such lot or parcel shall be excluded from the assessment district and shall not be assessed for such improvements if within the time and in the manner provided in section 48-579, subsection C the owner or owners file a written objection to the extent of the assessment district.
9. Order the construction or reconstruction of any work incidental to or connected with the improvements set forth in this subsection.
10. Pursuant to section 48-622, and notwithstanding any other law, construct, acquire or improve a wastewater treatment facility, drinking water facility or nonpoint source project with monies borrowed from or financial assistance including forgivable principal provided by the water infrastructure finance authority of Arizona.
B. In addition to all powers specifically granted by or reasonably inferred under the provisions of this article, cities and towns, acting through their governing bodies, may:
1. Join with other cities or towns or any improvement district or sanitary district or the state, or any of its departments or agencies, the federal government or any of its departments, agencies or instrumentalities, in the construction, operation or maintenance of improvements authorized by this section.
2. Join with any other city, town, improvement district or sanitary district in improving streets running upon or along the boundaries of the city or town and levy assessments or issue bonds for the proportionate part of the city or town of the cost of the improvement.
3. Accept from the state, or federal government, or any agency, department or instrumentality of either, grants for or in aid of the construction of any of the improvements provided by this article, and enter into contracts with the state, the federal government, or any agency, department or instrumentality of either or both, for the construction or supervision of construction by the state, the federal government or any agency, department or instrumentality of either or both of any such improvements, in accordance with the plans, specifications, rules and regulations of the state, the federal government, or any agency, department or instrumentality of either or both, but reserving to the city or town the right to assess against the property benefited by the improvement, and located within the city or town, that portion of the cost of the improvement which does not qualify for aid under the state or federal grant.
Section 48-576 of the Statutes requires the City Council to pass a resolution or ordinance of intention to order improvement, and reads:
48-576. Resolution or ordinance of intention to order improvement
A. Before ordering an improvement authorized by this article, the governing body of the municipality shall pass a resolution or ordinance of intention so to do, briefly describing the improvement. By the resolution or ordinance and the proceedings subsequent thereto, one or more improvements may be made on one or more streets and shall constitute one improvement and be constructed under one or more contracts. The resolution or ordinance of intention may be combined in a single resolution or ordinance of intention to open, extend, widen, straighten or close public streets or off-street parking areas pursuant to section 48-505. If the work proposed is already done for a lot, the lot shall be excepted from the assessment therefore to the extent of the work done.
B. When the proposed improvement, in the opinion of the governing body, is of more than local or ordinary public benefit, it may order the expense of the improvement chargeable upon a district, and shall describe the extent of the district in general terms in its resolution or ordinance of intention, either by reference to street lines or block numbers, or by designating its exterior boundaries by their courses and distances from the street or streets the improvement of which is contemplated, and may refer for a more particular description thereof to a map on file with the city or town engineer, showing the exterior boundary lines of the district, and delineating block and lot numbers or containing such details as will show the location of the lines. A city or town shall not assess the costs of an improvement which is for the general public benefit against land in an assessment district. If a portion of the expense of an improvement is for general public benefit, the city or town shall assess the district only that portion of the expense which benefits the property within the district.
C. The governing body, in the resolution or ordinance of intention, may provide that the improvement described therein may be made according to any of several alternative plans and specifications, or methods, classes or kinds of construction, or classes and kinds of material to be thereafter determined by the legislative body.