Where the city stops
Drive north or east far enough from Old Town and you cross a line that isn’t on the pavement: the edge of Scottsdale. Past it, if no other city or town has claimed the land, you are in unincorporated Maricopa County, and the county is the only local government you have. The Board of Supervisors acts as the council. County Planning and Development handles zoning and building permits, often under rural zoning with large minimum lots. The county transportation department maintains the public roads, and many private dirt roads are nobody’s job but the neighbors’. Sheriff’s deputies, not city police, answer the calls.
Fire protection comes from a fire district, a small special government with its own property tax, or in some areas from a private subscription service, the model Lou Witzeman’s Rural Metro pioneered when Scottsdale itself was unincorporated.
No city tap
The biggest difference is water. No city is obliged to serve land outside its limits. Homes rely on private wells, on small private water companies regulated by the Arizona Corporation Commission, or on hauled water delivered to a tank by truck. That last arrangement is only as secure as the place the trucks fill up.
Rio Verde Foothills
That is what the world learned on January 1, 2023. Rio Verde Foothills, an unincorporated community northeast of Scottsdale, had grown to more than 500 homes on water hauled from a Scottsdale standpipe. Citing Colorado River shortages and its Drought Management Plan, the city stopped selling hauled water to non-residents, and prices in the Foothills multiplied overnight. Under Mayor David Ortega, the city argued it owed its limited water to its own residents; the community argued it had been left with no way to get any. The 2020s chapter follows the story, and the Scottsdale water guide explains the city’s supplies.
How the legislature stepped in
The fix came from the state. Earlier, on August 31, 2022, the supervisors had rejected a proposed domestic water improvement district for the Foothills. In 2023 lawmakers of both parties passed SB 1432, and Governor Katie Hobbs signed it on June 19. It created the Rio Verde Foothills Standpipe District, a temporary government that could buy water from outside sources and have Scottsdale treat it and sell it to haulers. The law didn’t make Scottsdale give up its own supply. Deliveries resumed under that deal in October 2023.
The permanent answer was a regulated utility. On November 29, 2023 the Corporation Commission approved EPCOR’s plan to build a standpipe for the Foothills. The temporary district expired at midnight on December 31, 2025, and EPCOR’s filling station on 176th Street south of Rio Verde Drive opened on January 1, 2026, with about 150 acre-feet a year set aside for the community.
Wildcat subdivisions
The Foothills grew as it did because of a gap in state water law. Since the 1980 Groundwater Management Act, a new subdivision in the Phoenix area must prove a 100-year assured water supply before lots can be sold. But Arizona defines a subdivision as six or more lots. Split a parcel into five or fewer and the rule doesn’t apply; split the pieces again and a neighborhood appears with no proven water. These wildcat developments are legal lot splits, and Hobbs noted when she signed SB 1432 that language addressing them hadn’t made it into the bill. The Arizona water law guide covers that fight.
Why Scottsdale annexed north
Unincorporated land doesn’t stay empty; it gets built under county rules. That was the logic behind the city’s biggest expansion. Between 1981 and 1984, under Mayor Herb Drinkwater, Scottsdale annexed huge stretches of raw desert toward Pinnacle Peak so that the city, not the county, would decide what got built there. By 1990 it covered about 185 square miles. The payoff is visible in Pinnacle Peak and Troon, built under Scottsdale’s desert design rules, and in the land the city later bought for the Preserve. The 1980s chapter and the annexation guide tell that story.
Why the neighbors incorporated
The same pressure worked in reverse. Residents on the rural lots between Phoenix and Scottsdale incorporated Paradise Valley in 1961 to keep one-acre zoning and avoid being swallowed. Carefree incorporated in 1984 after a court fight with Scottsdale, to avoid annexation; Cave Creek followed in 1986 to stay out of Phoenix. Fountain Hills voted to incorporate on its third try in 1989, its backers later recalling that the community sent the county about $2 million in taxes and got little police protection or street maintenance in return.
Today state law makes that harder. With narrow exceptions, territory within six miles of a city of 5,000 or more can incorporate only with that city’s approval, or after the city rejects a petition to annex it. For communities on Scottsdale’s edge, that means the city has a real say in whether they can govern themselves.
County islands
Annexation also leaves gaps: county islands, unincorporated pockets surrounded by a city. They keep county zoning and the Sheriff, often with city services all around them. State law lets island residents form a county island fire district to pay for fire protection, and the county’s 2026 levy list includes one for islands in Scottsdale’s planning area. Whether to annex them is a recurring and usually slow conversation, because annexation needs petitions signed by a majority of the property owners.