By the late 1910s, a "natural prairie road" linked
Oroville to
State Highway Route 3 southeast of
Chico, following the present Table Mountain Boulevard, Openshaw Road, and Oroville-Chico Highway to Midway (Route 3). The primary route between these two cities was the all-state highway route, following
Route 21 (now
SR 162) west from Oroville to Route 3 near
Richvale.
Butte County dedicated a newly improved Oroville-Chico Highway on July 4, 1926; it became part of the state highway system in 1933 as the northern portion of the
Woodland-Chico
Route 87. (The rest of Route 87 became part of
Sign Route 24, which turned east at Oroville along present
State Route 70, in 1934.) In the 1950s and 1960s, about three-quarters of the Oroville-Chico Highway was absorbed by other routes. A new two-lane alignment of
U.S. Route 99E (
Legislative Route 3, now
SR 99) between east of
Richvale and Chico opened in the mid-1950s, using part of the Oroville-Chico Highway south of Durham Dayton Highway and bypassing the remainder to the junction south of Chico. In the early 1960s,
U.S. Route 40 Alternate (
Legislative Route 21, now
SR 70) was relocated due to the damming of
Lake Oroville across its old alignment. The bridge over the
West Branch Feather River northwest of the dam opened in August 1962, resulting in US 40 Alt. using the Oroville-Chico Highway (which was relocated to a new four-lane
freeway alignment) south of Wicks Corner. The remainder, which was never part of a sign route, became Route 149 in the
1964 renumbering. SR 149 was relocated onto a new two-lane alignment in the mid-1970s, leaving behind Openshaw Road. Caltrans estimated completion in late 2009 for the completion of the four-lane
expressway, including a new directional interchange at each end, at which State Route 70 and State Route 99 will exit and enter to the right of the main Oroville-Chico movement. Most access was closed, with Shippee Road providing the sole at-grade crossing of the expressway, and an overcrossing near State Route 70 giving access to local property. Shippee Road was relocated to the southeast, allowing for the future construction of an interchange. In addition, State Route 70 was relocated to the west between SR 149 and
State Route 191, and local access on State Route 99 between SR 149 and the Durham Dayton Highway interchange was replaced by
frontage roads. The entire project was completed in November 2008, at a cost of $125 million. ==Major intersections==