 The 1990s saw more construction of four @-@ lane roads along US 30 . Stretches of four @-@ lane roads that had already been constructed were extended towards other communities . In Story County , it was widened to four lanes from the I @-@ 35 interchange to US 65 at Colo . The original 1950s @-@ era bypass of Marshalltown was itself bypassed in 1997 by a freeway three @-@ quarters mile ( 1 @.@ 2 km ) south of the original bypass . That road , Iowa Avenue in Marshalltown , was designated as U.S. Highway 30 Business , the first business route along US 30 in Iowa . The four @-@ lane stretch southeast of Cedar Rapids was extended another five miles ( 8 @.@ 0 km ) to a point two miles ( 3 @.@ 2 km ) west of Mount Vernon , costing $ 5 @.@ 6 million ( equivalent to $ 8 @.@ 45 million in 2016 dollars ) to build . 
