State Route 989 (Tangerine Rd) is a mysterious route. Originally, it was officially an unsigned state highway that was a part of a proposed plan for highways in the Tucson area. However, most of these routes have been seemingly scrapped. SR 989 is marked as a "Signed Highway (Not SHS) Non-ADOT" on the State Highway System map; meaning that it's technically a state highway, but also not. According to Wikipedia, ADOT claims that SR 989 was given back to Oro Valley, however the route is still being maintained by ADOT it seems. Major evidence that points to this would be the signals at Tangerine & Innovation Park Dr. being ADOT standard signals, not Oro Valley's signals. Additionally, there is an ADOT mile marker for mile 35 that is still actively being maintained.
SR 989 is the highest numbered state highway in Arizona.
Page last updated: 2/26/2022