Interstate 175 Florida
Interstate 175 (South Bay Drive) constitutes the southern freeway spur connecting I-275 with Tropicana Field and Downtown St. Petersburg. The second shortest Interstate in Florida, I-175 is only one-tenth of a mile longer than nearby Interstate 375 (North Bay Drive). The freeway doubles as Florida State Road 594, which extends one block east of the freeway end to SR 687 (3rd Street South) north.
Serving the St. Petersburg Innovation District, a new ramp opened from 4th Street S northbound to I-175 west by Summer 2017. Planned since 2005, the $600,000 project was funded by the Florida Department of Transportation (FDOT). The connection improved access to the Interstate system from Johns Hopkins All Children’s Hospital, the University of South Florida St. Petersburg and the Dali Museum.1
When Interstate 75 was relocated to the east Tampa bypass in Hillsborough County in the late 1970s, five miles of eligible Interstate mileage became available for use elsewhere in Florida. Some of this unused mileage was allocated for the South Bay Drive spur to Downtown St. Petersburg (Interstate 175).
South Bay Drive was constructed in tandem with North Bay Drive (I-375) in two phases between 1977 and 1980. Work on the final link for the freeway, between 9th Street S (Martin Luther King, Jr. Street) and 4th Street S, commenced in 1977.2 Interstate 175 opened to traffic without fanfare on July 23, 1980 at total cost of $8.5-million. However it was not officially included in the Interstate System until November 1982.3
West End – St. Petersburg, FL
East End – St. Petersburg, FL
- Mileage – 1.44
- Cities – St. Petersburg
- Junctions –
Source: December 31, 2018 Interstate Route Log and Finders List
I-175 Annual Average Daily Traffic (AADT)
|Vehicles per day||Location|
|45,500||I-275 to MLK St S|
|30,500||MLK St S to 6th St S|
|20,500||6th St s to 4th St S|
Source: 2018 AADT – Florida Traffic Online
East End – St. Petersburg, Florida
State Road 687 (4th Street S) reaches the entrance ramp to Interstate 175 west at Delmar Terrace S. Two lanes depart for the 1.44-mile long connector to Interstate 275. SR 687 ends at the adjacent intersection with 5th Avenue S (SR 594) while 4th Street S continues into the Bartlett Park neighborhood. Photos taken 07/10/11 and 10/08/17.
4th Street S north at
4th St S north at the entrance ramp to Interstate 175 that opened to traffic in 2017. Photos taken 10/08/17.
West End – St. Petersburg, Florida
Passing over 28th Street S on the approach to I-175 (South Bay Drive) east on I-275 northbound. I-175 and I-375 depart within three quarter miles of each other along the periphery of Downtown St. Petersburg. Photos taken 07/06/13.
- “New downtown St. Pete on-ramp expected to be a boon for Innovation District.” Tampa Bay Business Journal. March 15, 2017.
- “I-275 south feeder is open downtown.” St. Petersburg Times, July 24, 1980.
- American Association of State Highway and Transportation Officials (AASHTO) Route Numbering Committee Meeting, November 19, 1982 (document).
Page updated May 21, 2019.