Burnside Street and turns due north as it climbs out of the below-grade trench, running parallel to 15th and 16th avenues. After an interchange with Glisan Street, the freeway becomes elevated and passes over cross-streets in the Pearl District, including those carrying the tracks of the Portland Streetcar's NS Line. A streetcar maintenance barn and railyard is located under the freeway between Marshall and Overton streets. At the northwest edge of Downtown Portland, I-405 intersects US 30, which continues northwest along a short freeway into the Northwest Industrial Area that was originally intended for the cancelled I-505. I-405 and US 30 become concurrent as they cross over the Willamette River on the eight-lane Fremont Bridge, a steel tied-arch bridge that carries southbound traffic on its upper deck and northbound traffic below. The double-decker freeway continues northeast over the Union Pacific Railroad's Albina railyard and Interstate Avenue, a part of Route 99W that also carries the MAX Yellow Line. The northern terminus of I-405 is at a stack interchange with I-5 in the Eliot neighborhood; US 30 continues southeasterly onto I-5 for a short distance before beginning a concurrency with I-84. A set of ramps continue northeast from the interchange to Legacy Emanuel Hospital along the alignment of the cancelled Rose City Freeway. I-405, also designated as Stadium Freeway No. 61, is the shortest Interstate freeway in the Portland area, at . It has a posted speed limit of due to its short distance between interchanges and high volume of merging traffic. The highway is maintained by the Oregon Department of Transportation (ODOT), who conduct an annual survey of traffic volume that is expressed in terms of average annual daily traffic (AADT), a measure of traffic volume for any average day of the year. The busiest section of I-405 is at Burnside Street, which carried a daily average of 131,400 vehicles in 2018; and the least-trafficked section, at Southwest Broadway, carried 84,400 vehicles. The freeway had an estimated 8 hours of northbound congestion and 11.8 hours of southbound congestion in 2017, with average speeds of for northbound traffic and for southbound traffic during weekday afternoon rush hours. TriMet operates one bus route on I-405, Line 24, which uses the Fremont Bridge as a connection between Slabtown and Legacy Emanuel Hospital. History Planning and routing dispute Highway planner Robert Moses was commissioned by the city government in 1943 to envision a program