Interstate 75 in Ohio
Interstate 75 runs from Cincinnati to Toledo by way of Dayton in the U.S. state of Ohio. The highway enters the state running concurrently with I-71 from Kentucky on the Brent Spence Bridge over the Ohio River and into the Bluegrass region. I-75 continues north into the Miami Valley and then passes through the Great Black Swamp before crossing into Michigan.
Route description
The highway enters the state via the Brent Spence Bridge into downtown Cincinnati. I-71 immediately splits off to the east from this point, taking a more easterly route through downtown, while I-75 continues north along the west side of downtown. The highway continues north, intersecting I-74 and turning to the northeast. The highway then intersects the Cincinnati beltway, I-275, and continues northeasterly through West Chester, Monroe, Middletown, and Franklin en route to the Dayton metropolitan area.Once arriving in the Dayton area, I-75 first junctions with I-675, an eastern bypass of Dayton, in Miamisburg. The highway then continues north into downtown Dayton, skirting it to the west, and junctioning with I-70 near the Dayton International Airport.
The highway then continues north through the western side of the state towards Toledo, passing through cities such as Troy, Piqua, Lima, Findlay, and Bowling Green. Once the highway arrives in Toledo, it first intersects with I-475 in Perrysburg, followed by I-80/I-90 in Rossford before skirting downtown Toledo to the west. After the interchange, I-75 continues north into Downtown Toledo. Just north of downtown, I-475 rejoins I-75. After continuing northeasterly, I-75 intersects I-280, which connects the Ohio Turnpike. Following this, I-75 enters Michigan and follows the shore of Lake Erie.
History
I-75 in Ohio was built through the 1960s, supplanting U.S. Route 25, though much of the freeway was built for US 25. By the time I-75 was finished, US 25 ran concurrently with I-75 for all but the northernmost section. By 1974, the US 25 designation was deemed unnecessary, and removed from Ohio and Michigan. The northernmost section of US 25 in Ohio became State Route 25.In 2005, ODOT considered reconfiguring I-75's existing interchange in Findlay with US 224 and SR 15 west as a diverging diamond interchange to improve traffic flow. Had it been constructed, it would have been the first such interchange in the United States. By 2006, ODOT had reconsidered, instead adding lanes to the existing overpass.
Traffic congestion in the Cincinnati–Dayton corridor has led to proposals for a regional I-75 bypass to divert through traffic.
The segment from West Chester to Middletown was widened in 2010. Construction on the highway continues from Middletown all the way to I-675.
On January 19, 2015, an overpass north of Hopple Street near Cincinnati collapsed onto the highway below at approximately 10:30 pm. The span that failed was the segment of the former northbound ramp to Hopple Street that passed over the southbound lanes of I-75. The overpass had been closed and was in the process of being removed after a replacement ramp was opened on December 26, 2014. The interstate underneath was open at the time of the failure. One construction worker on the overpass was killed during the collapse by a falling steel beam. A truck driver was injured when his semi hit the fallen overpass immediately after the collapse. One other worker was in a backhoe on the bridge but was uninjured.
In Dayton, ODOT recently completed total reconfiguration of I-75 with several projects occurring simultaneously. The intersection of I-75 and I-70 was reconfigured to handle an increased traffic load at the intersection. I-75 through downtown Dayton at the intersections of Ohio State Route 4, US 35, and between were widened and modernized.
Between I-475 in Perrysburg and SR 15 in Findlay, I-75 is only two lanes wide in each direction, and extremely congested, because of traffic headed towards Dayton via I-75, and Columbus via SR 15 and US 23. As of July 2014, initial stages of a widening project have begun in order to widen this stretch of road to three lanes in each direction, with an estimated completion date of November 2016. A few miles later, I-75 intersects with I-80/I-90.
Future
Work began in May 2019 to convert the existing interchange with Union Centre Boulevard in West Chester Township, Butler County to a diverging diamond interchange. The $20 million project is scheduled to be completed in summer 2020. There are also plans to convert the existing interchange with SR 725 in Miamisburg to a DDI. The project will not be built until 2023 and its projected cost is $4.1 million, entirely funded by the state.In Cincinnati, approximately of the highway will be totally reconfigured by three separate ODOT projects happening simultaneously. The Brent Spence Bridge Corridor project will replace the Brent Spence Bridge and continue north to the Western Hills Viaduct. The Mill Creek Expressway project will modernize the Mill Creek Expressway segment of the highway, from the Western Hills Viaduct to the Ronald Reagan Cross County Highway interchange. The Thru the Valley project will continue from the Cross County Highway north to Interstate 275. These projects will improve safety by eliminating all left-hand exit ramps and increasing vehicular capacity.
Exit list
Auxiliary routes
| Interstate | City | Type | Notes | |
| Interstate 275 | Cincinnati | Loop | Extends into Indiana and Kentucky | |
| Interstate 475 | Toledo | Bypass | Intersects the Ohio Turnpike | |
| Interstate 675 | Dayton | Bypass | Connects to I-70 |