Interstate 74 in Iowa

I-74 begins at a trumpet interchange with I-80 on the northern edge of Davenport where it heads to the south. From I-80 to the East 67th Street overpass, the freeway is surrounded by farmland on either side. South of the overpass, it passes a residential area to the east and a commercial area to the west. The East 53rd Street exit provides access to shopping centers on both sides of the interstate.[3]

Continuing south between East 53rd Street and Spruce Hills Drive, I-74 goes through an area of sparse development. What businesses there are have frontages on either Elmore Avenue to the west or Utica Ridge Road to the east; the backs of these businesses abut the freeway.[3] At the Spruce Hills Drive exit, U.S. Route 6 (US 6) joins from the west. Nearly ¹⁄₃ mile (0.54 km) to the west, Spruce Hills Drive becomes Kimberly Road, which carries US 6 through Davenport until it intersects I-280 on the western edge of the Quad Cities.[4]

South of Spruce Hills Drive, I-74 runs parallel to the eastern leg of Kimberly Road, which turned south at its intersection with Spruce Hills Drive. The freeway curves slightly to the southeast and enters Bettendorf. It crosses Duck Creek and meets Middle Road at a diamond interchange.[4]

As I-74 and US 6 head down a hill towards the Mississippi River, a series of exit and entrance ramps connect the freeway to US 67, which runs northbound along State Street and southbound along Grant Street. The interstate passes over US 67 and railroad tracks belonging to the Dakota, Minnesota and Eastern Railroad on an elevated highway, which serves as the approach to the Interstate 74 Bridge over the Mississippi River. Despite the singular name, the crossing is actually two twin bridges which each carry one direction of traffic to and from Moline, Illinois.[4]

I-74 crosses the Mississippi River via the twin spans of the I-74 Bridge.

An interstate bisecting the Quad Cities was planned as early as 1955

I-74 was part of the original plans for building Iowa's interstate system.[5] It would form the Iowa leg of a planned freeway from the Quad Cities to Cincinnati, Ohio.[6] Its route through the Quad Cities closely resembles the path drawn up in the mid-1950s.[4][7]

In the Iowa Quad Cities, I-74 opened in three segments beginning on August 30, 1968. On that day, the northernmost 3 miles (4.8 km), from I-80 to US 6, opened to traffic. The new freeway was built atop farmland west of Utica Ridge Road in the northeastern part of Davenport.[8] The next section was built adjacent to the north–south portion of Kimberly Road, which then carried US 6 through Bettendorf. The segment ended where the interstate lined up with the older street. The eastbound exit and westbound entrance ramps at Kimberly Road now provide access to and from US 67. The middle section opened in 1971.[2]

Another three years passed before the freeway was completed and opened to traffic. The twin spans of the I-74 Bridge had to be retrofitted to connect to the interstate. The Iowa-bound bridge was built as a Works Progress Administration project in 1934–35 and the Illinois-bound bridge was 24 years later.[9] Prior to interstate construction, the I-74 Bridge terminated at State Street, the northbound lanes of US 67, in Bettendorf. To prevent traffic bottlenecks, traffic was prohibited from making left turns onto and off of the bridges. As a result, loop ramps diverted traffic onto Gilbert Street, one block south of State Street, which curved back to State Street at both ends thus allowing traffic to make the necessary left turns.[10]

Construction of the interstate meant eliminating the at-grade intersections with State and Grant streets. I-74 was built as elevated highway from the bridges to a new overpass at Kimberly Road. The connections were completed and opened to traffic on November 26, 1974.[2]

The Iowa and Illinois departments of transportation are in the planning stages to build a new bridge to replace the aging I-74 Bridge. The Iowa-bound bridge opened in 1935; the Illinois bridge in 1958.[9] In addition to replacing the bridges, the scope of the bi-state coalition's plan includes updating 7 miles (11 km) of I-74 mainline and interchanges from 53rd Street in Davenport to the Avenue of the Cities in Moline.[11]

In 2005, the Iowa and Illinois DOTs identified the traffic needs of the corridor and found they would be satisfied by a true-arch, tied-arch, or cable-stayed bridge. After public input and consideration of construction costs and aesthetics, the departments of transportation, in August 2006, recommended building two twin, true arch, basket handle bridges.[12] U.S. Senator Mark Kirk of Illinois has suggested charging a toll upon motorists who use the new bridges to help pay for their construction. However, a 1998 study, which researched all river crossing options to replace the bridges, deemed new tolls were not viable.[13]

In addition to the new river crossing, the mainline of I-74 between 53rd Street in Davenport and the Avenue of the Cities in Moline will be widened from a four-lane freeway to six lanes. Additional lanes will be picked up and dropped in selected locations. The new bridge itself will be eight lanes, with entrance ramps at US 67 becoming a lane on the Illinois bound bridge, and then exiting at River Drive in Moline. On the Iowa bound span, River Drive entrance ramps in Moline will create a new lane across the bridge, exiting at US 67. In downtown Bettendorf, the connection to US 67 will be simplified. US 67 traffic will be routed in both directions along Grant Street. State and Grant streets are currently a one-way couplet through Bettendorf. A network of ramps and city streets form the interchange as it is now. A full-access interchange will be built in its place at Grant Street.[14]

Construction along the corridor has already been completed at the 53rd Street interchange. A partial cloverleaf interchange was being added in each direction to allow traffic to enter I-74 without making left turns at its intersection with 53rd Street. This phase of construction ended around December 2012.[15]

The entire route is in Scott County.

Location	mi[1]	km	Exit[4]	Destinations	Notes
Davenport	0.000	0.000	—	I-80 – Des Moines, Chicago	National western end of I-74; I-80 exit 298
	1.497	2.409	1	53rd Street – Hamilton Tech College
	2.877	4.630	2	US 6 west (Spruce Hills Drive, Kimberly Road)	Western end of US 6 overlap
Bettendorf	3.870	6.228	3	Middle Road, Locust Street
	4.623	7.440	4	US 67 (Grant Street, State Street) – Riverfront
Mississippi River	5.386	8.668	I-74 Bridge; Iowa–Illinois state line
				I-74 east / US 6 east – Peoria	Continuation into Illinois
1.000 mi = 1.609 km; 1.000 km = 0.621 mi       Concurrency terminus