North of I-380, Iowa 150 intersects 51st Street. Prior to 1984, Iowa 150 came from the north along its current route and turned east onto 51st Street and Iowa 101 followed the current path of Iowa 150 to Vinton. The highway heads due north, only passing a few houses until it reaches US 20 south of Independence. Once in Independence, it crosses the Wapsipinicon River over a concrete arch bridge. At 1st Street, the route turns east for two blocks before returning northward. On the north side of town, Iowa 150 passes the Independence Motor Speedway.