List of Interstate Highways in California

This is a list of Interstates in the U.S. state of California that have existed since the 1964 renumbering. It includes routes that were defined by the California State Legislature but never built, as well as routes that have been entirely relinquished to local governments.

Interstate Highways in California
Standard Interstate signage in California
Highway names
Interstates	Interstate XX (I-XX)
US Highways	U.S. Route XX (US XX)
State	State Route XX (SR XX)
System links
State highways in California Interstate U.S. State Pre-1964 History Unconstructed Deleted Freeway Scenic

Each state highway in California is maintained by the California Department of Transportation (Caltrans) and is assigned a Route (officially State Highway Route[1][2]) number in the Streets and Highways Code (Sections 300-635). Under the code, the state assigns a unique Route X to each highway, and does not differentiate between state, US, or Interstate highways.

Overview

• Lengths for each state route were initially measured as they were during the 1964 state highway renumbering (or during the year the route was established, if after 1964) based alignment that existed at the time, and do not necessarily reflect the current mileage. Portions of some routes have been relinquished to or are otherwise maintained by local or other governments, and may not be included in the length listed below. Several routes are broken into non-contiguous pieces, and their lengths may not reflect the overlaps that would be required to make them continuous. Some routes may also have a gap because it is either explicitly defined in the California Streets and Highways Code or due to an unconstructed portion, and the listed length may or may not reflect the gap.
• If a route was renumbered, the old or new number is given in the "notes" column.
• The years are when legislative action was taken, not when real-world changes were made.
• Concurrences are not explicitly codified in the Streets and Highways Code; such highway segments are listed on only one of the corresponding legislative route numbers—for example, the I-80/I-580 concurrency, known as the Eastshore Freeway, is only listed under Route 80 in the highway code while the definition of Route 580 is broken into non-contiguous segments. When a highway is broken into such segments, the total length recorded by Caltrans only reflects those non-contiguous segments, and does not include those overlaps that would be required to make the route continuous.
• Since the 1990s, a number of piecemeal relinquishments have been made. These are generally reflected in the length but not the termini.
• Former termini are not shown if they are along the current route, meaning that the route was simply extended.
• One Interstate Highway—Interstate 305—is defined only federally; the state calls it part of US 50. It was signed as part of Business Interstate 80, the only state-maintained Interstate business route in California.

Primary Interstates

Number	Length (mi)[3][lower-alpha 1]	Length (km)	Southern or western terminus	Northern or eastern terminus	Formed	Removed	Notes
I-5	796.432	1,281.733	Mexican border in San Ysidro, San Diego	I-5 at the Oregon state line	01947-01-011947	current
I-5W	—	—	I-5 near Tracy	I-5 near Dunnigan	01957-01-011957	01970-08-091970	Former designation of I-580 and I-505
Future I-7	302	486	I-5 at Wheeler Ridge	I-5 at Stockton	proposed	—	Caltrans has proposed I-7 or I-9 for SR 99 in central California
I-8	171.98	276.77	Nimitz Boulevard, Sunset Cliffs Boulevard in San Diego	I-8 at the Arizona state line	01964-01-011964	current	Westernmost segment between Nimitz Boulevard/Sunset Cliffs Boulevard and I-5 is not officially recognized as an Interstate by the FHWA
Future I-9	302	486	I-5 at Wheeler Ridge	I-5 at Stockton	proposed	—	Caltrans has proposed I-7 or I-9 for SR 99 in central California
I-10	243.31[lower-alpha 2]	391.57	SR 1 in Santa Monica	I-10 at the Arizona state line	01947-01-011947	current	Route 10, as defined by the state, is broken into two segments at the East Los Angeles Interchange; traffic is directed via I-5 to connect the two; the portion between I-5 and US 101 not signed
I-15	287.26[lower-alpha 3]	462.30	I-8 in San Diego	I-15 at the Nevada state line	01957-01-011957	current
I-15E	—	—	I-15 in Temecula	I-15 in Devore, California	01973-01-011973	01982-01-011982	Renumbered from I-215 in 1973 and back to I-215 in 1982
I-40	154.623	248.842	I-15 in Barstow	I-40 at the Arizona state line	01947-01-011947	current
I-80	205.07	330.03	US 101 in San Francisco	I-80 at the Nevada state line	01947-01-011947	current	Westernmost segment between US 101 and the Bay Bridge is not officially recognized as an Interstate by the FHWA
Former       Future

• 
  I-5 southbound approaching Mount Shasta
• 
  I-8 in Alpine
• 
  I-10 eastbound with the San Gorgonio Pass wind farm in the background
• 
  I-15 northbound descending into the Ivanpah Valley towards Primm, Nevada at the California-Nevada state line
• 
  I-40 eastbound near Fenner
• 
  I-80 eastbound in the Sierra Nevada from the Yuba Gap overpass towards the western approach to Donner Summit

Auxiliary Interstates

Number	Length (mi)[3][lower-alpha 1]	Length (km)	Southern or western terminus	Northern or eastern terminus	Formed	Removed	Notes
I-105	18.82	30.29	SR 1 in El Segundo	I-605 in Norwalk	01982-01-011982	current	Right-of-way formerly planned as part of SR 42
I-105	—	—	I-5 in East Los Angeles	US 101 in Los Angeles	01964-01-011964	01968-01-011968	Renumbered as US 101; part of East Los Angeles Interchange
I-110	23.73[lower-alpha 3]	38.19	SR 47 in San Pedro	I-10 in Los Angeles	01978-01-011978	current	Former routing of US 6/SR 11
I-110	—	—	I-10/I-5 in East Los Angeles	US 101 in Los Angeles	01964-01-011964	01968-01-011968	Deleted from highway system; part of East Los Angeles Interchange
I-180	—	—	US 101 in San Rafael	I-80 in Berkeley	01981-01-011981	01991-01-011991	Former designation of I-580
I-205	12.973	20.878	I-580 near Tracy	I-5 near Manteca	01970-01-011970	current	Formerly part of US 50
I-210	44.90[lower-alpha 3]	72.26	I-5 in Los Angeles	SR 57 in Glendora	01964-01-011964	current	Entire length of SR 210 to be renumbered to I-210. SR 57 from I-10 to I-210/SR 210 is an unsigned designation of I-210 used by the FHWA and AASHTO
I-215	55.060	88.610	I-15 in Murrieta	I-15 in San Bernardino	01982-01-011982	current	Formerly I-15E and SR 215
I-238	2.126[lower-alpha 3]	3.421	I-580 in Castro Valley	I-880 in San Leandro	01983-01-011983	current	Technically a spur of I-80; only violation in the Interstate system
I-280	57.510	92.553	US 101/I-680 in San Jose	King and 5th Streets in San Francisco	01955-01-011955	current
I-305	5.64	9.08	I-80 in West Sacramento	SR 99 in Sacramento	01981-01-011981	current	Unsigned designation used by the FHWA and the AASHTO; signed as part of US 50
I-380	1.67	2.69	I-280 in San Bruno	US 101 in South San Francisco	01964-01-011964	current	Formerly proposed to be extended west to SR 1 and east along the Southern Crossing to I-880
I-405	72.415	116.541	I-5 in Irvine	I-5 near San Fernando	01964-01-011964	current
I-480	—	—	US 101 in San Francisco	I-80 in San Francisco	01957-01-011957	01968-01-011968	Demoted to state highway in 1968
I-505	32.99	53.09	I-80 in Vacaville	I-5 near Dunnigan	01977-01-011977	current	Formerly part of I-5W
I-580	75.550[lower-alpha 2]	121.586	US 101 in San Rafael	I-5 near Tracy	01947-01-011947	current	Various segments formerly part of US 50, I-5W or SR 17
I-605	27.40	44.10	I-405/SR 22 in Seal Beach	I-210 in Irwindale	01964-01-011964	current
I-680	70.536	113.517	US 101/I-280 in San Jose	I-80 in Fairfield	01955-01-011955	current	Formerly part of SR 21
I-710	24.249[lower-alpha 4]	39.025	SR 47 in Long Beach	Valley Boulevard in Alhambra	01984-01-011984	current	Formerly part of SR 7. The portions north of I-10 and south of SR 1 are not officially recognized as Interstates by the FHWA
I-780	6.759	10.878	I-80 in Vallejo	I-680 in Benicia	01976-01-011976	current	Formerly part of I-680
I-805	28.016	45.087	I-5 in San Ysidro, San Diego	I-5 in Sorrento Valley, San Diego	01959-01-011959	current
I-880	45.698	73.544	I-280/SR 17 in San Jose	I-80/I-580 in Oakland	01984-01-011984	current	Formerly part of SR 17
I-905	8.964	14.426	I-5 in San Diego	Mexican broder near Otay Mesa	proposed	—	Currently SR 905
I-980	2.027	3.262	I-880 in Oakland	I-580/SR 24 in Oakland	01981-01-011981	current	Right-of-way formerly part of SR 24
Former       Future

• 
  Construction on I-215 between Inland Center Drive and Orange Show Road in San Bernardino
• 
  I-280 running along near Stanford University
• 
  Cars driving on I-405 through the Sepulveda Pass
• 
  I-580 winding through the Altamont Pass wind farm
• 
  I-605 northbound approaching its northern terminus with I-210
• 
  I-680 northbound descending from Mission Pass
• 
  An empty I-805 at its interchange with I-8 in San Diego's Mission Valley

See also

•  California Roads portal

Notes

1. Lengths rounded to the nearest mile or tenth-mile are estimated from various sources including Google Maps.
2. This route is broken into pieces, and the length does not reflect the overlaps that would be required to make the route continuous.
3. Part of one of the contiguous routes that is partially signed as an Interstate Highway, while the remaining segment is signed as a state highway.
4. This route is broken into pieces due to a gap in the description, unfilled by any route.

References

1. "Section 231" . California Streets and Highways Code – via Wikisource.
2. California Department of Transportation. "Other State Highway Routes". Sacramento: California Department of Transportation.
3. California Department of Transportation. "State Truck Route List". Sacramento: California Department of Transportation. Archived from the original (XLS file) on June 30, 2015. Retrieved June 30, 2015.

External links