of public improvements that would begin after the end of World War II to provide employment for returning soldiers. Among these were a network of "thruways" for Portland, including a downtown loop consisting of the Foothills Thruway (later forming I-405) and the East-Side Thruway (later I-5), connected by a northern crossing of the Willamette River. The Foothills Thruway would run along Northwest 24th Avenue and terminate at two intersections with Harbor Drive at the Ross Island Bridge to the south and the new Willamette River bridge to the north. A city study released in June 1955 proposed the construction of several freeways in downtown Portland, including the Sunset Freeway and Stadium Freeway—later combined to form I-405. The northern crossing would use the double-decker Fremont Bridge, which had been proposed earlier as part of U.S. Route 99W in the 1920s but defeated in public referendums. The federal Bureau of Public Roads included the Stadium Freeway in its 1955 recommendation for a national system of expressways that were later funded by the Federal-Aid Highway Act of 1956. The freeway was estimated to cost $71 million in 1958 dollars (equivalent to $ in dollars) and would be funded primarily by the federal government under the Interstate Highways program. The Oregon Highway Division studied a set of five alternate routes for the freeway, designated as Interstate 405 by the federal government in 1958, with input from the city government over potential impacts to the west side of the central business district. The southern section from the Marquam Bridge to US 26 near Southwest Jefferson Street was split into two options: the Clay–Market route, following Clay and Market streets to the north of Portland State College; and the Foothills route, which would curve along the southwest side of an urban renewal area with a depressed roadway. The northern section from US 26 to the Fremont Bridge was split into three options: an elevated freeway between 15th and 16th avenues proposed by the city; an elevated freeway between 18th and 19th avenues; and a depressed roadway between 21st and 22nd avenues. The city government, Portland State College, and downtown business groups lobbied in support of the Clay–Market route, producing their own study that claimed it would preserve downtown property values. The Oregon State Highway Commission and Bureau of Public Roads preferred the Foothills route due to its $4 million (equivalent to $ in dollars) in cost