K-150 (Kansas highway)

Before state highways were numbered in Kansas there were auto trails, which were an informal network of marked routes that existed in the United States and Canada in the early part of the 20th century. The western terminus of K-150 connects to the former Old Santa Fe Trail, South West Trail, National Old Trails Road and Kansas-Oklahoma-Texas Highway. The eastern terminus connects to the former New Santa Fe Trail.[9]

US-50 at its junction with K-150

K-150 was first designated a state highway in a July 1, 1937 resolution and at that time ran from US-50N and US-77 eastward to US-50S.[2] It was first noted on the 1937 Kansas state roadmap.[10][11] On June 27, 1956, the AASHO Route Numbering Committee approved US 56, between Springer, New Mexico, and Kansas City, Missouri. At this time US-50N was renumbered to US-56 and US-50S was renumbered to US-50.[12]

The route has changed little, but in August 2001, work began on a $17.5 million (equivalent to $26 million in 2021[13]) project to reconstruct the entire length of K-150. New bridges were built, asphalt shoulders were added and the sight distances were improved. Work was completed by August 2003.[14] In 2012, KDOT decided that the western terminus was to be rebuilt as an enhanced roundabout.[15] Construction on the $5.416 million (equivalent to $6.12 million in 2021[13]) enhanced roundabout at the western terminus began in June 2015. The roundabout was enhanced by leaving in place the shooflies that were installed to take traffic around the site during construction. This allows oversized trucks that wouldn't fit on the roundabout to pass.[16][17] K-150 was closed from early September 2015, to late December 2015, and traffic was detoured south along US-77 to make room for construction on that section of the roundabout. The roundabout was completed and open to traffic in December 2015.[18]

On January 5, 1955, a second K-150 was established in Johnson County. It began at K-7 in Olathe and began traveling eastward and soon reached an interchange with I-35, US-50 and US-56. At this point it was joined by US-169, and the two routes continued east to an interchange with US-69. Here US-169 turned north as K-150 continued east to the Missouri border, where it became Route 150.[19] The highway was decommissioned on March 31, 1996, when US-169 was realigned to travel further north along I-35.[20] Also, Olathe and Overland Park had annexed more land around K-150, and would have run entirely through city limits, which is against Kansas law.[21]