California State Route 46

State Route 46 begins at SR 1 southeast of Cambria, about one mile (1.6 km) from the Pacific Ocean. It heads east as the Eric Seastrand Highway across the Santa Lucia Range on a relatively straight roadway built in the 1970s, bypassing the steep, curvy Santa Rosa Creek Road. After passing near several wineries, this first segment ends at US 101 north of Templeton, where SR 46 turns north, overlapping the US 101 freeway through the valley formed by the Salinas River to central Paso Robles. Immediately after splitting from US 101, SR 46 crosses the Salinas River, passing near the Paso Robles Municipal Airport, and then heads east through a hilly area with several wineries and the community of Whitley Gardens. It then runs partially alongside the Estrella River to a merge with SR 41 near Shandon and a rest area. There, it turns northeast, following Cholame Creek through Cholame Pass between the Cholame Hills and Temblor Range to the settlement of Cholame and the split with SR 41. After crossing into Kern County, the highway continues to rise as it heads east up the Antelope Grade to a summit near Bluestone Ridge before descending through Polonio Pass into the San Joaquin Valley. State Route 46 takes the southernmost crossing of the Diablo Range, which is one of the routes linking the Central Valley to the coast. Interstate 580, State Route 152, and State Route 46 are the major routes that cross the Diablo Range. This route is heavily used when the Grapevine is closed. Truckers who do not want to take SR 58 through Tehachapi can use this route to head to I-5 to the Bay Area, Northern California, and vice versa. Many people from the Bay Area also use this route to head to Tehachapi Pass to head to Interstate 40, the Antelope Valley, Las Vegas, and Mount Whitney if they do not want to use I-5.[2][3]

Descending into Cholame westbound on SR 46. The Cholame Hills are visible in the distance.

Once it enters the San Joaquin Valley, SR 46, known as the Paso Robles Highway, follows an almost perfectly straight eastward alignment, crossing SR 33 at Blackwells Corner, passing through the Lost Hills Oil Field, and intersecting I-5 about two miles (3.2 km) past Lost Hills and the crossing of the California Aqueduct. SR 46 then passes through the Semitropic Oil Field about seven miles (11 km) west of Wasco. SR 46 and SR 43 overlap for a short distance in the city of Wasco, and then SR 46 passes over Calloway Canal and Friant Canal before it ends at SR 99 in Famoso. The county-maintained Famoso Road continues east across SR 65 and into the Sierra Nevada foothills.[2][3]

East of Paso Robles, SR 46 is part of the California Freeway and Expressway System,[4] and east of US 101 is part of the National Highway System,[5] a network of highways that are considered essential to the country's economy, defense, and mobility by the Federal Highway Administration.[6] The highway from SR 1 to SR 41 near Cholame is an eligible State Scenic Highway,[7] but it is not officially designated as a scenic highway by the California Department of Transportation.[8]

As part of the second state highway bond issue, approved by the state's voters in 1916, Route 33 was created, linking the San Joaquin Valley trunk (Route 4, now SR 99) near Bakersfield with the coast trunk (Route 2, now US 101 in Paso Robles, passing through the Coast Ranges via Cholame Pass.[9][10] The road was not yet built in 1919 when the Automobile Blue Book recommended only the county-maintained "very poor road" (now SR 58) via Simmler as a connection between the valley and Central Coast.[11] By 1925, the Cholame Pass highway had been improved,[12] and paving was completed in December 1930.[13] An extension west to Route 56 (now SR 1) near Cambria was added in 1933;[14][15] however, it ran along Santa Rosa Creek Road, north of today's alignment.[16]

The state sign route system was established in 1934 but the majority of Route 33 did not receive a state route designation, instead becoming part of the new U.S. Route 466. However, US 466 turned southwest from Cholame Pass along Legislative Route 125 (modern SR 41) to Morro Bay. Sign Route 41, which followed Legislative Route 125 northeast of Cholame, continued along Route 33 west to the coast.[17][18][19][20] However, Route 125 had still not been paved between Cholame and Atascadero by the 1950s and so US 466 was moved to the longer but better-quality Route 33 via Paso Robles, replacing SR 41 to Paso Robles and overlapping US 101 to Atascadero. As SR 41 had not been signed over the unpaved road west of Paso Robles, it was truncated to Cholame.[21] US 466 was eliminated in the 1964 renumbering, becoming SR 46 east from Paso Robles. However, instead of going south and west to Morro Bay, SR 46 continued west to Cambria and the road via Creston and Atascadero to Morro Bay (which had since been paved) became part of SR 41.[22][23] A new two-lane expressway carrying SR 46 west from Paso Robles[24] was built in the mid-1970s, replacing Santa Rosa Creek Road.[16]

The James Dean Memorial Junction, looking northeast, with SR 41 heading away from the camera

The two-lane stretch from Paso Robles to Cholame was once known as 'Blood Alley' for the large number of vehicle incidents, mainly head-on collisions, among the high volume of commuters, truck drivers and tourists.[25] Between 2000 and 2010, a total of 38 people were killed.[26] As of 2016, 'Blood Alley' was widened to a four-lane expressway from the junction of US 101 to just east of the west junction of SR 41, near the town of Shandon. The east junction of the SR 46/SR 41 split is named after actor James Dean, who was killed in a car crash near this site on September 30, 1955. [27] The current intersection is now marked as the James Dean Memorial Junction. The junction was officially dedicated as the James Dean Memorial Junction on September 30, 2005 as part of the State of California's official commemoration of the 50th anniversary of Dean's death.[28] However, this is not the actual intersection where the accident occurred, contrary to popular belief. The accident scene is about 100 feet to the south of the current intersection, where the road used to be. The California Department of Transportation (Caltrans) carried out an interim safety project west of Cholame in December 1995, mandating daytime headlights and installing thermoplastic striping, a concrete barrier and rumble strips. Caltrans has plans to start widening the section between SR 33 and I-5 in 2017. There are also plans to upgrade SR 46 west of this segment and build an interchange with SR 41 at the James Dean Memorial Junction.[29][30]

Except where prefixed with a letter, postmiles were measured on the road as it was in 1964, based on the alignment that existed at the time, and do not necessarily reflect current mileage. R reflects a realignment in the route since then, M indicates a second realignment, L refers to an overlap due to a correction or change, and T indicates postmiles classified as temporary (for a full list of prefixes, see California postmile § Official postmile definitions).[1] Segments that remain unconstructed or have been relinquished to local control may be omitted. The numbers reset at county lines; the start and end postmiles in each county are given in the county column.

County	Location	Postmile [1][16][31]	Exit [32]	Destinations	Notes
San Luis Obispo SLO R0.15-60.85	​	R0.15		SR 1 – Cambria, Hearst Castle, Harmony, Cayucos, Morro Bay	West end of SR 46
	Paso Robles	R21.97 54.12[N 1]		US 101 south / Ramada Drive	Interchange; west end of US 101 overlap; US 101 exit 228
		​	West end of freeway on US 101
		55.67[N 1]	229	Spring Street (US 101 Bus. north)	Eastbound exit and westbound entrance
		​	230	Pine Street	Westbound exit and entrance
		​	230	Paso Robles Street	Eastbound exit only
		56.88[N 1]	231A	16th Street	Westbound exit and eastbound entrance
		​	East end of freeway on US 101
		57.92[N 1] 29.76		US 101 north / CR G14 (24th Street) – Paso Robles	Interchange; east end of US 101 overlap; US 101 north exit 231, south exit 231B
	Shandon	48.63		SR 41 south (West Centre Street) / McMillan Canyon Road – Shandon, Creston	West end of SR 41 overlap; former US 466 west; also accessible westbound via a left turn at East Centre Street
	​	49.60	Shandon Rest Area
	Cholame	55.11		SR 41 north – Fresno	East end of SR 41 overlap
Kern KER 0.00-57.79	​	​	Polonio Pass
	Blackwells Corner	20.54		SR 33 – Coalinga, McKittrick, Taft
	​	27.48		Brown Material Road, Halloway Road
	Lost Hills	32.53		I-5 (West Side Freeway) – Sacramento, Los Angeles	Interchange; I-5 exit 278
	​	43.02		Rowlee Road – Buttonwillow
	Wasco	50.90		SR 43 south (F Street) to I-5 south – Shafter, Central District	West end of SR 43 overlap
		51.22		SR 43 north / J Street – Corcoran	East end of SR 43 overlap
	Famoso	57.78		SR 99 – Delano, Bakersfield	Interchange; east end of SR 46; former US 99 / US 466 east; SR 99 exit 44
		57.78		Famoso Road – Famoso	Continuation beyond SR 99
1.000 mi = 1.609 km; 1.000 km = 0.621 mi       Concurrency terminus       Incomplete access

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Wikimedia Commons has media related to California State Route 46.

• Caltrans: State Route 46 highway conditions
• Caltrans Traffic Conditions Map
• California Highway Patrol Traffic Incidents
• California Highways: State Route 46
• California @ AARoads.com - State Route 46