Strategic Interregional Corridors

Corridor descriptions from the 2015 ITSP

San Diego – Mexico Border – Inland Empire Connections: 

  • Forms the main link between Mexico and Southern California through two separate connections. The two connection points primary purpose is to accommodate the flow of goods and people moving between the US and Mexico. The two connections serve interregional and intraregional trips, providing access to local, recreational, and freight facilities. The connections are shorter in length compared to other interregional corridors within California, but they have a strong importance and value as the largest direct international connections in the State.

South Coast – Central Coast Corridor

  • Connects the Central Coast to Southern California, linking urbanized Southern California with the more rural counties further north. The major travel patterns along the corridor include freight movement, recreational tourism, and local commuter traffic. The major interregional transportation facilities are US 101, I-5, and the Pacific Surfliner intercity rail corridor. The majority of the corridor is within urbanized areas, with a limited rural segment in the northern portion in Santa Barbara County. The corridor accommodates goods movement via highway and railroad.

Central Coast – San Jose/San Francisco Bay Area Corridor

  • Connects the Central Coast to San Jose and San Francisco Bay region. US 101 is the major interregional transportation facility that traverses the entire corridor, with intercity rail services, including a future high-speed-rail corridor covering part of the corridor in the northernmost portion. The Central Coast, particularly the Salinas Valley is home to the top vegetable-producing region in the nation.  US 101 also serves the National Guard training installations at Camp Roberts, Fort Hunter Liggett and provides access to Vandenberg Air Force Base. The route is significant for goods movement and serves the agriculture and food processing and packaging industries that form the economic base for much of the Central Coast. In addition to connecting with the southern portion of the San Francisco Bay Area, US 101 connects the Salinas Valley agricultural production areas to the northern San Joaquin Valley via SR 156 and SR 152. The SR 41 and SR 46 corridor connects the San Luis Obispo and Paso Robles area with the central San Joaquin Valley and the food processing and distribution facilities located along the SR 99 corridor.

San Jose / San Francisco Bay Area – North Coast Corridor

  • The corridor is the coastal south-north connector linking the San Francisco Bay Area to California’s North Coast. US 101 is the primary transportation facility used for interregional travel and serves as a lifeline for the movement of people, goods, and services. The corridor follows the coast north in the western portion of the State through Marin, Sonoma, Mendocino, Humboldt, and Del Norte Counties. The corridor is vital to the area’s recreational tourism and economy and serves urban and suburban areas, such as Santa Rosa, San Rafael, and numerous smaller communities. Much of US 101 passes through areas of geological instability, sensitive environmental, cultural and historical resources. Projects along the corridor must be developed in collaboration with State, federal, local and tribal partners to balance transportation needs with impacts to resources.

San Jose / San Francisco Bay Area – Central Valley – Los Angeles Corridor

  • The Corridor links southern and northern California and is significant business, recreational tourism, and freight movement corridor. This corridor has modal options for the movement of people and freight through major freeways (SR 99, I-5, and I-580), passenger rail services (San Joaquin, Amtrak Thruway Bus Service, and high-speed rail), freight rail (UPRR and the BNSF), and interregional buses (Greyhound Lines, BoltBus, Megabus and Transportes Intercalifornias). These facilities and modes, linked to local streets and transit systems, provide the basic transportation framework for an integrated interregional transportation system. The two major parallel north-south highways, I-5 and SR 99, that have very different characteristics and needs. Along the western edge of the San Joaquin Valley, I-5 primarily provides connectivity between the urban areas of the San Francisco Bay Area and Sacramento and the urban areas of the Los Angeles region. In between these two mega regions, along the I-5 corridor, there are almost no communities, no industry beyond agricultural production, and commercial services limited to gas stations, fast food establishments, and a few motels or hotels. The four-lane Interstate is characterized by high-speed, long-distance travel by autos and trucks.

Sacramento Valley – Oregon Corridor

  • This is an important connection between California and states to the north and ultimately provides an international connection to Canada. The corridor supports the movement of people and freight, including recreational travel, and provides important connection for emergency response and resiliency for the region. Much of the Sacramento Valley is utilized for agricultural purposes and is dependent on this corridor for exporting products and importing farming and ranching supplies. The southern portion of the corridor begins in the urbanized area of Sacramento. Between the northern portion of Sacramento and Red Bluff, there are two parallel facilities traversing different communities (1) I-5 goes through Woodland and (2) SR 70, SR 149, and SR 99 provide access to and through Marysville, Yuba City, Oroville, and Chico terminating in Red Bluff at the junction of SR 36 two miles from I-5. The northern portion of the corridor is more rural with Red Bluff and Redding the major urbanized areas before reaching the Oregon border.

High Desert – Eastern Sierra – Northern Nevada Corridor

  • The corridor is an eastern California, north-south corridor and traverses the east side of the Sierra Nevada mountain range. The corridor provides a consistent high LOS for local trips and interregional and interstate movement of people, goods, and recreational travel. It also provides lifeline accessibility for rural communities where there are no alternative routes to access goods and services or for detours in the event of a road closure.
  • Recreation (60 percent) and goods movement (20 percent) account for most trips on the corridor. Tourism (domestic and international) is the major economic activity with over 13 million visitor-days generated annually including the following destinations: National Parks such as Yosemite and Death Valley; Inyo and Humboldt-Toiyabe National Forests; State Parks such as Red Rock and Bodie; Mammoth Mountain Ski Area; and Mono Lake Basin National Scenic Area.
  • The corridor provides access to the military facilities of Edwards Air Force Base, China Lake Naval Air Weapons Station, and US Marines Pickel Meadows Mountain Warfare Training Center. Variable amounts of interregional trips are generated by military activities.

 Southern California – Southern Nevada / Arizona Corridor

  • The corridor connects Southern California’s seaport gateways, and the massive logistics and manufacturing sectors that are based in the region to the rest of the country via three Interstate highways (10, 15, and 40) and parallel freight rail routes owned and operated by UPRR and BNSF. The region is the nation’s largest and most important freight gateway and corridor for international trade. Also, I-15 and I-40 link to the San Joaquin Valley via SR 58 and provide connectivity to the southern United States for the nation’s most productive agricultural region in the Central Valley.
  • The I‐15 Corridor begins in San Diego, near the Port of San Diego, and continues through the urban core. North of SR 163, I-15 is a well‐developed, freeway ranging from 8 to 12 lanes. Portions of the I‐15 include 20 miles of high‐occupancy-vehicle (HOV) and high-occupancy toll (HOT) express lanes on a cross‐section of 10 and 12 lanes. Between Escondido and I‐40 in Barstow the corridor is a six to eight‐lane freeway, and becomes a four‐lane freeway north of Barstow, continuing to Las Vegas, Nevada.
  • Santa Monica is the western terminus for I-10. The entire I-10 facility within the Los Angeles metropolitan area ranges from an 8 to 12 lane freeway, continuing into San Bernardino and Riverside counties, collectively known as the Inland Empire. This area contains the nation’s highest density and extent of warehousing facilities serving not only the vast consumer market in Southern California but the US Southwest as well. The route and parallel and connecting freeways are characterized by very high truck volumes and frequent traffic congestion. I-10 becomes a four highway outside of Indio, California connecting to Arizona and beyond.

Central Coast and San Joaquin Valley East-West Connections

  • The Central Coast and San Joaquin Valley are connected through two separate corridors that provide access for people and freight which support the economy through the agricultural industry and tourism. The northern interregional corridor providing connectivity between the regions is made up of SR 156 and SR 152 and the southern interregional corridor consists of SR 41 and SR 46. These corridors are instrumental in the movement of freight, specifically agricultural products. The connections are also vital to the movement of people between the regions and experience very heavy seasonal and weekend recreational travel by Central Valley residents to access coastal areas. SR 46 connects with SR 58 in the southern Central Valley. SR 58 provides vital connectivity for the Valley to I-15 and I-40.

San Jose / San Francisco Bay Area – Sacramento – Northern Nevada Corridor

  • The primary west-east connection between the San Francisco/San Jose (Bay Area) and Reno, Nevada, and areas east of Nevada. Interstate 80 (I-80) is a transcontinental highway route, starting in San Francisco and terminating in the State of New Jersey. The Union Pacific Railroad (UPRR) parallels I-80 throughout the corridor and serves as a transcontinental rail route accommodating freight and passenger services. Both the highway and the railroad provide national connectivity for San Francisco Bay Area seaports and the agricultural region of the Great Central Valley and the Salinas Valley.  The general transportation movements that impact interregional performance include daily commute congestion; congestion between port facilities and the local, regional, and interregional road systems; recreational travel between the San Francisco Bay Area and the Truckee/Lake Tahoe areas; freight and passenger rail shared track conflicts; and seasonal weather disruptions.

North Coast – Northern Nevada Connections

  • The corridor consists of two separate east-west northern California highway corridors between the coast to the eastern part of California and Nevada. The first corridor is from Humboldt County to Lassen County and on to Reno and it includes segments of SR 299, 44, 36, and US 395. The second corridor is from Mendocino County to Nevada County and I-80 (portions of SR 20, SR 29, and SR 53). These routes provide access to communities throughout the region, supporting the regional economy and providing connection to emergency services and vital health and human services.
  • The two major interregional facilities travel through mostly rural areas connecting rural communities, urban areas, and tribal reservations. The interregional facilities provide the corridor with vital connections to the interstate system and the rest of the State, providing access to basic goods and services along with routine and emergency medical services. These routes support the local economy, including freight movement and recreational tourism, and are the major transportation corridors for response and recovery efforts in case of emergencies such as forest fires.