The Tampa Bay area is home to over 4,000,000. Clearwater anchors northern Pinellas County while St. Petersburg with its Downtown along Tampa Bay, spreads across the southern peninsula. Tampa, home to both MacDill Air Force Base and Port Tampa Bay, encircles Hillsborough Bay to the east, with unincorporated suburbs expanding outward to encompass Brandon, Riverview and Ruskin.
The original layout for the Tampa Bay Interstate network took I-4 west from Tampa to St. Petersburg and I-75 south from Pasco County to the Downtown Interchange near Ybor City. Changes were announced by the U.S. Department of Transportation in January 1969, when I-75 was routed southward over I-4 west from Downtown Tampa to Pinellas as part of its extended alignment south to Naples.
The Tampa Bay Regional Planning Council requested Federal approval of an Interstate highway loop on January 20, 1967. This included the missing link of the I-75 extension from Tampa to Miami and a separate beltline route through Pinellas County. The plan outlined routing I-75 around Tampa from a point near Bearss Avenue southward to the end of the four-laned Sunshine Skyway. The existing I-75 south to the Downtown Interchange would become a spur, and Interstate 4 would continue south through St. Petersburg to the Sunshine Skyway.1
Eventually Federal officials approved a designation of I-75W through Pinellas County and I-75E for the bypass through the Hillsborough County side of the bay. $14 million in construction to connect I-75 with the Sunshine Skyway and to bring the span to Interstate standards was underway by 1973. This included $6.1 million for the highway from Gandy Boulevard to 46th Avenue N, $3.4 million for the portion from 46th Avenue N to 38th Avenue N, and $4.3 million for the link from 38th Avenue N to 22nd Avenue N. Those were to be completed by mid-1974. The $7.3 million segment from 22nd Avenue N to 5th Avenue N went to bid in June 1973.2
Concerns over costs to bring the Skyway up to Interstate standards resulted in discussion about potential renumbering. Possibilities for redesignating I-75 through Pinellas County included extending I-4 south to the Skyway or renumbering it as a spur route (I-175) or a loop (I-275).2 The American Association of State Highway Officials (AASHO) ultimately approved a Florida Department of Transportation (FDOT) request to redesignate I-75 as Intertate 275 on June 26, 1973.3
The following are key dates in the history of Interstate 275 in Florida:4
- 1973 – I-275 created when I-75 is realigned from the St. Petersburg-Tampa route to the Tampa Bay bypass. I-275 was complete at that time from 38th Street N in St. Petersburg north to Lutz. The portion of I-275 between the Sunshine Skyway (near Maximo Point) and 38th Street N was unconstructed.
- 1975 – I-275 under construction from 5th Avenue S north to 38th Street N.
- 1977 – I-275 opened from 5th Avenue S north to 38th Street N in St. Petersburg.
- 1980 – I-275 under construction from I-75 near Gillette west to Terra Ceia. Tragedy struck I-275 when the ship Summit Venture collided with the original Sunshine Skyway. 35 people died in this accident, and one of the two spans collapsed.
- 1981 – I-275 under construction from Maximo Point north to 5th Avenue S. The northern apex of I-275 tied into I-75 near Worthington Gardens in Pasco County.
- 1983 – Two sections of I-275 opened: the southern apex with I-75 and the section of I-275 from Maximo Point north to 5th Avenue S.
- 1984 – Replacement Sunshine Skyway (a new cable-stayed bridge) was under construction.
- 1987 – New Sunshine Skyway opened on April 30th. At that point, Interstate 275 was complete.
Interstate 275 crosses the cable stayed Sunshine Skyway Bridge over the mouth of Tampa Bay. On May 9, 1980, the southbound span of the original Sunshine Skyway Bridge (a steel truss bridge) collapsed when the Summit Venture freighter collided with a bridge support. This led to two-way traffic on the remaining northbound span until the replacement was built. Ultimately, the old bridge was removed, though portions of the approach in both directions were retained for use as fishing piers run by the state park system.
The Sunshine Skyway opened to traffic following a ribbon cutting ceremony on April 30, 1987.5 Festivities were held for the $240 million span on February 7, 1987. Events included a public bridge walk a parade along the north causeway and a dedication ceremony held at Blackthorn Park.6 Construction of the 76 foot diameter concrete pillars supporting the concrete segmental bridge got underway September 24, 1982. The pillars were placed at 1,200 foot intervals, 400 feet farther apart than the old Skyway Bridge.7 The 24 piers holding the northern half of the cable-stayed span were in place by February 1985 as work progressed on the 40 foot wide roadway decks. Construction on the piers for the Skyway’s southern half continued along with the pylons for the two 425 foot high towers.7,8 The 1,200 foot long main span provided 175 feet of navigational clearance.8
Work on the Skyway fell behind schedule due to cracks forming in the concrete segments. Although $16 million over budget, it was previously scheduled to open in August 1986.9 Further delays plagued the project when a gantry used to lift a 220 ton section of concrete roadway collapsed on July 30, 1984. Bridge contractors also took longer to cast the roadway segments than previously anticipated, pushing back completion to Fall 1986.10
When the 22,000 foot long Sunshine Skyway opened to traffic, portions of the former bridge were repurposed into fishing piers. 3,360 feet of the Pinellas County pier were retained while the Manatee County pier represented one of the longest piers in the world at 8,400 feet in length. The steel superstructure of the old bridge was dismantled and sold as scrap. Some of the rubble from the concrete support columns from the old span was used to create artificial reefs nearby.8