State Route 198 is an east-west state highway in the U.S. state of California that runs from U.S. Route 101 south of King City to Sequoia National Park. It connects the California Central Coast to the mid–Central Valley through Hanford and Visalia, although the most developed portion is in the Central Valley itself. SR 198 intersects the major north-south routes in the Central Valley, including Interstate 5, SR 33, and SR 99. The highway that would become SR 198 was approved for construction in the 1910s through three bond issues, and was added to the state highway system in 1934. Parts of the highway were upgraded to freeway during the 1960s. Another portion was converted to an expressway in between Hanford and Visalia, and was completed in late 2012.
All of SR 198 was added to the state highway system in the three bond issues floated to pay for the construction of the system. The first bond issue, approved by the state's voters in 1910, included the road from Visalia west to Hanford, connecting the two county seats with the central north-south highway. As part of the 1916 bond issue, the route was extended west from Hanford through Coalinga to the coast trunk highway near San Lucas, and assigned it the Route 10 designation. The third bond issue, passed in 1919, included a further extension east from Visalia to Sequoia National Park. The entire length of Route 10 was marked as Sign Route 198 in 1934, and this number was adopted legislatively in the 1964 renumbering. The portion east of Interstate 5 near Coalinga was added to the California Freeway and Expressway System in 1959, and parts of it have been built as such. The construction of the freeway east of Visalia to Road 192 was approved in January 1961, with the remainder of the freeway unplanned at that time as contingent on the routing of SR 65. The projected cost in 1958 of the entire freeway east of Visalia was $13 million and was scheduled to be completed by 1964. The freeway through Visalia was completed by 1965, with an expressway connecting it to US 99. Also completed was the expressway heading west out of Hanford, with part of it access-controlled west of Lemoore. Construction began in November 2009 on a project to widen a two-lane, 10-mile section of SR 198 between SR 43 and SR 99 into a four-lane expressway. The $60 million project was completed in December 2012.
Future
The Kings County Association of Governments has plans to improve the state highways within the county. Developers are interested in building distribution warehouses in Kings County because of its strategic location midway between the Los Angeles and San Francisco Bay areas, but they are currently turned off by the lack of freeway access. For SR 198, the plan is to extend the freeway segment from Naval Air Station Lemoore to I-5. However, Kings County voters have shown little interest in passing any transportation taxes to fund these projects.