# Interstate 605

Interstate 605 (abbreviated I-605, officially known as the San Gabriel River Freeway and locally referred to as The 605) 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 in Orange County to I-210 just south of the Irwindale–Duarte border in Los Angeles County. 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.

## Route description

The entirety of I-605 is defined in the state highway system as Route 605. It is defined as such in the California Streets and Highways Code's section 619:
   Route 605 is from: (a) Route 1 near Seal Beach to Route 405. (b) Route 405 to Route 210 near Duarte.
   Route 605 shall be known and designated as the “San Gabriel River Freeway.”
The interchange with I-405 and SR 22 was built to accommodate an unconstructed future extension south to SR 1 as outlined in subdivision (a). The distance is traversable via nearby Seal Beach Boulevard, but Caltrans has no intention to adopt the road as part of Route 605.
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) just south of the Irwindale–Duarte border. Ramps from I-605 then extend north to Huntington Drive in Duarte.
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. I-605 is one of the only Southern California freeways without 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.

## History

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.
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.

## Exit list

| County | Location | mi | km | Exit | Destinations | Notes |
| Orange | Seal Beach | 0.00 | 0.00 | 1A | SR 22 west (7th Street) – Long Beach | Southern terminus; SR 22 east exit 2; I-405 north exit 24; I-405 south/SR 22 east is former SR 7 south |
| Orange | Seal Beach–Los Alamitos line | 0.41 | 0.66 | 1B | I-405 south (San Diego Freeway) / SR 22 east (Garden Grove Freeway) – Garden Grove | Southern terminus; SR 22 east exit 2; I-405 north exit 24; I-405 south/SR 22 east is former SR 7 south |
| Orange | Seal Beach–Los Alamitos line | 0.41 | 0.66 | — | 405 Express Lanes south to SR 22 east | Southern terminus; SR 22 east exit 2; I-405 north exit 24; I-405 south/SR 22 east is former SR 7 south |
| Orange–Los Angeles county line | Seal Beach–Los Alamitos– Long Beach tripoint | 0.41 | 0.66 | 1C | 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 Street is via exit 2A |
| Coyote Creek | Coyote Creek | 1.60 | 2.57 | Bridge | Bridge | Bridge |
| Los Angeles | Long Beach | 1.69 | 2.72 | 2A | Willow Street | Southbound exit only |
| Los Angeles | Long Beach | 1.93 | 3.11 | 2B | Spring Street / Cerritos Avenue | Southbound exit and northbound entrance |
| Los Angeles | Long Beach–Lakewood line | 3.38 | 5.44 | 3 | Carson Street / Lincoln Avenue | Former US 91 and SR 18 |
| Los Angeles | Lakewood–Cerritos line | 4.51 | 7.26 | 5A | Del Amo Boulevard | |
| Los Angeles | Cerritos | 5.39 | 8.67 | 5B | South Street | |
| Los Angeles | Cerritos | 6.69 | 10.77 | 7A | SR 91 (Artesia Freeway) | SR 91 east exit 17, west exit 17B |
| Los Angeles | Cerritos–Norwalk line | 7.45 | 11.99 | 7B | Alondra Boulevard | |
| Los Angeles | Norwalk | 8.50 | 13.68 | 9A | Rosecrans Avenue | |
| Los Angeles | Norwalk | 9.29 | 14.95 | 9B | I-105 west (Century Freeway) / Imperial Highway | Signed as exits 9B (I-105) and 9C (Imperial Highway) northbound; I-105 east exits 18A-B; Imperial Highway is former SR 90. |
| Los Angeles | Norwalk | 9.53 | 15.34 | 10 | Firestone Boulevard | Former SR 42 |
| Los Angeles | Downey | 11.25 | 18.11 | 11 | Florence Avenue | |
| Los Angeles | 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 |
| Los Angeles | Santa Fe Springs | 11.89 | 19.14 | 12 | Telegraph Road | Former US 101 Byp. north; former SR 26 |
| Los Angeles | West Whittier-Los Nietos | 13.18 | 21.21 | 13 | Slauson Avenue | |
| Los Angeles | West Whittier-Los Nietos | 13.69 | 22.03 | 14 | Washington Boulevard | Signed as exits 14A (west) and 14B (east) southbound |
| Los Angeles | West Whittier-Los Nietos–Whittier line | 15.21 | 24.48 | 15 | Whittier Boulevard (SR 72) | Former US 101 |
| Los Angeles | Whittier–Pico Rivera line | 16.05 | 25.83 | 16 | Beverly Boulevard | Southbound access to Beverly Boulevard west is via exit 17 |
| Los Angeles | Pico Rivera–Industry line | 17.21 | 27.70 | 17 | Rose Hills Road | |
| Los Angeles | Industry | 18.29 | 29.43 | 18 | Peck Road | |
| Los Angeles | Industry | 19.05 | 30.66 | 19 | SR 60 (Pomona Freeway) – Los Angeles, Pomona | SR 60 exit 12 |
| Los Angeles | Avocado Heights–Industry line | 21.03 | 33.84 | 21 | Valley Boulevard | Former US 60 and SR 212 |
| Los Angeles | 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 |
| Los Angeles | Baldwin Park–Irwindale line | 22.71 | 36.55 | 23 | Ramona Boulevard – Baldwin Park, El Monte | Former US 99 |
| Los Angeles | Irwindale | 23.79 | 38.29 | 24 | Lower Azusa Road / Los Angeles Street | |
| Los Angeles | Irwindale | 25.16 | 40.49 | 25 | Live Oak Avenue | Northbound exit and southbound entrance |
| Los Angeles | Irwindale | 26.60 | 42.81 | 26 | Arrow Highway | Southbound exit and northbound entrance |
| Los Angeles | Irwindale | 27.40 | 44.10 | 27A | I-210 east (Foothill Freeway) – San Bernardino | I-210 exits 36A-B (exit 36B signed as Mount Olive Drive) |
| Los Angeles | Irwindale | 27.40 | 44.10 | 27B | I-210 west (Foothill Freeway) – Pasadena | I-210 exits 36A-B (exit 36B signed as Mount Olive Drive) |
| Los Angeles | Irwindale–Duarte line | 27.54 | 44.32 | 27C | Huntington Drive (Historic US 66) – Duarte | Northern terminus; at-grade intersection; former US 66 |
| ​ | Irwindale–Duarte line | 27.54 | 44.32 | | Mount Olive Drive | Continuation beyond Huntington Drive |
| 1.000 mi = 1.609 km; 1.000 km = 0.621 mi Electronic toll collection Incomplete access |||||||