|San Gabriel River Freeway|
|Auxiliary route of I-5|
|Maintained by Caltrans|
|Length||27.40 mi (44.10 km)|
|History||1940s as a state highway, 1964 as a number|
|South end||I-405 / SR 22 in Seal Beach|
|North end||I-210 / Huntington Dr. in Duarte|
|Counties||Orange, Los Angeles|
Interstate 605 (abbreviated I-605, officially known as the San Gabriel River Freeway) is a 27-mile-long (43 km) major north–south auxiliary Interstate Highway in the Greater Los Angeles urban area of Southern California. It runs from I-405 and State Route 22 (SR 22) in Seal Beach to I-210 in Duarte. The San Gabriel River Freeway closely parallels the San Gabriel River for most of its alignment, hence its name, which is one of the few Southern California freeways not named after a city along its route.
Aside from changes to the interchange with I-105 (which did not open until the early 1990s), and the addition of an HOV lane between I-405 and I-10, I-605 is one of the only remaining freeways that kept its original alignment throughout its run through Los Angeles County since it first opened.
The California Streets and Highways Code defines Route 605 as "(a) Route 1 near Seal Beach to Route 405. (b) Route 405 to Route 210 near Duarte." However, the portion in subsection A has yet to be constructed.
The southern terminus of I-605 is at the San Diego (I-405) and Garden Grove (SR 22) Freeways in Seal Beach. From there, it runs roughly north through the Gateway Cities of the Los Angeles Basin. It then shifts north-northeast, crossing the Whittier Narrows and across the San Gabriel Valley. I-605 then ends at its junction with the Foothill Freeway, (I-210) in Duarte, a small city located at the foothills of the San Gabriel Mountains.
I-605 follows most of the length of the San Gabriel River from the San Diego Freeway in Seal Beach to the Santa Fe Dam. Typically dry riverbed and flood basins are visible from many portions of the route, especially near the northern terminus.
In the mid 2000s, a HOV lane was added for motorists with two or more people to use between I-405 and I-10. The HOV lane ends at I-10 and there are no plans to extend it to I-210 at this time. With the addition of the HOV lane, the left shoulder was eliminated to avoid massive costs to widen the freeway. The highway also suffers from traffic jams regularly, especially the junction with I-5 (the Santa Ana Freeway). Newer signs with exit numbers replaced the older signs between the Orange County line and I-10 in 2016, with the completion of the I-605 and I-10 junction improvement. Guide signs along I-605 never included destinations (control cities) such as "Seal Beach" or "Irwindale" since its opening. Rather, cardinal directions ("NORTH" or "SOUTH"), and a simple "THRU TRAFFIC" designation in place of control cities, are used on signs along I-605 itself.
I-605 is part of the California Freeway and Expressway System, and is part of the National Highway System, a network of highways that are considered essential to the country's economy, defense, and mobility by the Federal Highway Administration. I-605 from I-405 to I-10 is known as the San Gabriel River Freeway, as named by Senate Bill 99, Chapter 1101 in 1967.
In 1957, the number for this route was proposed as I-13, as it is positioned approximately midway between I-5 and I-15 (although it intersects the former). That number was rejected, as was the second proposed number, I-102. Finally, the designation I-605 was accepted in 1958.[unreliable source?]
I-605 began construction in 1963 and the first section was opened in 1964 from I-405 to SR 60. The newest section (extension to I-210) was opened in 1971 was originally signed as SR 243. There are plans to extend it to SR 1 further south in Orange County as SR 605, but strong community opposition means that it is unlikely that the alignment will ever be built.
In 2020, there was a proposal to widen I-605, which would have added four new lanes to 12 mi (19 km) of I-605 between Norwalk and El Monte, California. This proposal was rejected due to strong community opposition, in particular due to the fact that it would have led to the destruction of houses in Downey, California.
SR 22 west (7th Street) – Long Beach
|Southern terminus; SR 22 exit 2|
|Seal Beach–Los Alamitos line||0.41||0.66||1B|
I-405 south (San Diego Freeway) / SR 22 east (Garden Grove Freeway) – Garden Grove
|Southbound exit and northbound entrance; former SR 7 south; I-405 north exit 24|
I-405 south / SR 22 east
|HOV access only; southbound exit and northbound entrance; future I-405 Express Lanes south|
|Seal Beach–Los Alamitos–|
Long Beach tripoint
I-405 north (San Diego Freeway) – Santa Monica
|Signed as exit 1A northbound; former SR 7 north; I-405 south exit 24A|
|Orange||Los Alamitos||1.41||2.27||1D||Katella Avenue / Willow Street||Signed as exit 1B northbound; southbound access to Willow St. is via exit 2A|
|Los Angeles||Long Beach||1.69||2.72||2A||Willow Street||Southbound exit only|
|1.93||3.11||2B||Spring Street / Cerritos Avenue||Southbound exit and northbound entrance|
|Long Beach–Lakewood line||3.38||5.44||3||Carson Street / Lincoln Avenue||Former US 91 and SR 18|
|Lakewood–Cerritos line||4.51||7.26||5A||Del Amo Boulevard|
|6.69||10.77||7A||SR 91 (Artesia Freeway) – Beach Cities, Riverside|
|Cerritos–Norwalk line||7.45||11.99||7B||Alondra Boulevard|
I-105 west (Century Freeway) / Imperial Highway
|Signed as exits 9B (I-105) and 9C (Imperial Hwy) northbound; I-105 east exits 18A-B; Imperial Hwy is former SR 90.|
|9.53||15.34||10||Firestone Boulevard||Former SR 42|
|Downey–Santa Fe Springs line||11.25||18.11||11||I-5 (Santa Ana Freeway) – Los Angeles, Santa Ana||Former US 101 Byp. south; I-5 exit 124|
|Santa Fe Springs||11.89||19.14||12||Telegraph Road||Former US 101 Byp. north; former SR 26|
|West Whittier-Los Nietos||13.18||21.21||13||Slauson Avenue|
|13.69||22.03||14||Washington Boulevard||Signed as exits 14A (west) and 14B (east) southbound|
|West Whittier-Los Nietos–Whittier line||15.21||24.48||15||Whittier Boulevard (SR 72)||Former US 101|
|Whittier–Pico Rivera line||16.05||25.83||16||Beverly Boulevard||Southbound access to Beverly Blvd. west is via exit 17|
|Pico Rivera–Industry line||17.21||27.70||17||Rose Hills Road|
|Industry||19.05||30.66||19||SR 60 (Pomona Freeway) – Los Angeles, Pomona||SR 60 exit 12|
|Avocado Heights–Industry line||21.03||33.84||21||Valley Boulevard||Former US 60 and SR 212|
|Baldwin Park||21.83||35.13||22||I-10 (San Bernardino Freeway) – Los Angeles, San Bernardino||Former US 99 / US 70 / US 60; I-10 east exits 31A-B, west exit 31A|
|Baldwin Park–Irwindale line||22.71||36.55||23||Ramona Boulevard – Baldwin Park, El Monte||Former US 99|
|Irwindale||23.79||38.29||24||Lower Azusa Road / Los Angeles Street|
|25.16||40.49||25||Live Oak Avenue||Northbound exit and southbound entrance|
|26.60||42.81||26||Arrow Highway||Southbound exit and northbound entrance|
|27.40||44.10||27||I-210 (Foothill Freeway) – Pasadena, San Bernardino||Signed as exits 27A (east) and 27B (west); I-210 east exit 36A, west exit 36B|
|Irwindale–Duarte line||27.54||44.32||27C||Huntington Drive (Historic US 66) – Duarte||Northern terminus; at-grade intersection; former US 66; road continues as Mount Olive Drive|
|1.000 mi = 1.609 km; 1.000 km = 0.621 mi|
- ^ "Route Log and Finder List - Interstate System: Table 2". FHWA. Retrieved October 7, 2007.
- ^ "Los Angeles Highways". Scvresources.com. Archived from the original on November 15, 2011. Retrieved January 26, 2013.
- ^ "Article 2 of Chapter 2 of Division 1". California Streets and Highways Code. Sacramento: California Office of Legislative Counsel. Retrieved February 6, 2019.
- ^ Federal Highway Administration (March 25, 2015). National Highway System: Los Angeles, CA (PDF) (Map). Scale not given. Washington, DC: Federal Highway Administration. Retrieved July 29, 2017.
- ^ Natzke, Stefan; Neathery, Mike & Adderly, Kevin (June 20, 2012). "What is the National Highway System?". National Highway System. Washington, DC: Federal Highway Administration. Retrieved July 1, 2012.
- ^ California Department of Transportation; California State Transportation Agency (January 2021). 2020 Named Freeways, Highways, Structures and Other Appurtenances in California (PDF). Sacramento: California Department of Transportation. p. 96. Archived from the original (PDF) on October 20, 2022.
- ^ a b Faigin, Daniel. "Interstate 605". California Highways. Retrieved September 23, 2016.
- ^ "Metro Board Unanimously Approves Motion to Delay 605/5 Freeway Widening and Instead Study Alternatives". Streetsblog Los Angeles. October 22, 2020. Retrieved December 8, 2020.
- ^ a b Warring, KS (April 18, 2008). "Interstate 605 Freeway Interchanges" (PDF). California Numbered Exit Uniform System. California Department of Transportation. Retrieved September 1, 2014.
- ^ "California Log of Bridges on State Highways: District 12" (PDF). Caltrans. California Department of Transportation. October 2006. Archived from the original (PDF) on February 20, 2007. Retrieved September 19, 2019.