Joining I-30 with I-40, Interstate 430 provides a both a western bypass of Little Rock and a commuter route. The I-430 bridge across the Arkansas River is the lone crossing of the waterway between Downtown Little Rock and Conway, some 25 miles to the northwest.
Early plans for both Interstate 430 and I-630 in western Little Rock originated in the mid-1950s. During that time period, University Avenue represented the western extent of the built up area of the capital city. Interstate 430 was constructed initially from Markham Street in west Little Rock to I-40 near Crystal Hill. The route was completed in 1975 at a total cost of $67 million.
The Big Rock Interchange, where I-430 converges with the west end of I-630, opened in 1977. Rapid development along the west side of the exchange resulted in a 400% increase of traffic within the vicinity along both freeways. The Arkansas Highway Commission authorized a study for area improvements in 2004. Plans for the interchange upgrade were announced in 2006.1
The first of three construction phases to rebuild the Big Rock Interchange commenced in January 2009.1 The third phase added two high speed flyovers. The interchange name was derived from a 5 million pound rock formation uncovered during construction. The nearly $150 million project was dedicated on July 8, 2015.2
The diamond interchange (Exit 5) with Shackleford Road on Interstate 430 was added sometime between 1982 to 1984. The addition of the exchange at Exit 5 coincided with expansion of I-430 to eight overall lanes northward from Shackleford Road to Rodney Parham Road (Exit 8).3