FDOT submitted to applications to the American Association of State Highway and Transportation Officials (AASHTO) for the formal establishment of both I-175 and I-375 on April 21, 1981.
This spur route, to be designated Interstate 175, functions as a connector route that provides access between Interstate 275, the St. Petersburg Central Business District and the Urban Highway network.
Specifically, this route is 1.439 miles in length and is a limited access four-lane facility built to Interstate standards. The west end of this route connects to Interstate 275 and continues to provide direct access to a principal arterial (SR 687/U.S. 92).
AASHTO rejected both routes, citing a lack of approval by the Federal Highway Administration (FHWA) in a letter dated July 1, 1981. Designating I-175 and I-375 as logical additions to the Interstate System, FDOT received concurrence from the FHWA following a formal request on September 3, 1981. A succeeding application for I-175 and I-375 to AASHTO was approved on November 20, 1982.3