Southeast Gateway Line
| Company type | Public transit project |
|---|---|
| Industry | Public transportation |
| Headquarters | Los Angeles , United States |
Area served | Southeastern Los Angeles County |
| Products | Light rail transit service |
| Owner | Los Angeles County Metropolitan Transportation Authority (Metro) |
| Website | www |
The Southeast Gateway Line—previously known as the West Santa Ana Branch Transit Corridor—is an upcoming light rail route that largely traces the historic path of the Pacific Electric West Santa Ana Branch. This line will provide a transit connection from Downtown Los Angeles to Artesia and several other municipalities situated in southeastern Los Angeles County.
Overview
With a budget allocation of $4 billion, Los Angeles Metro plans to commence construction in 2022, financed through the Measure M transportation initiative. The project is structured to be developed in two distinct phases.
In June 2017, Metro issued a request for proposal (RFP) aimed at evaluating different alternatives for the corridor. The agency eventually narrowed down to two feasible options and prepared to release the Draft EIS/EIR for public review, which was anticipated in 2020.
The project's schedule was expected to gain momentum as part of the Twenty-eight by '28 program. By 2021, the environmental impact report projected an estimated cost of $8.6 billion.
In April 2024, the City of Cerritos initiated legal action seeking modifications to the proposed alignment within its jurisdiction. Metro's plan includes a $687 million elevated bridge crossing shared with Artesia, whereas Cerritos advocates for an underground alternative costing $1.1 billion. Metro argued that the $413 million cost difference did not justify changing plans.
By 2023, Metro considered renaming the project since it would not extend to Santa Ana or into Orange County. Having been in development for approximately twenty years, the $8.5 billion initiative anticipates construction between 2025 and 2035. On January 22, 2024, Los Angeles County Supervisor Janice Hahn revealed the new designation: the Southeast Gateway Line.
On March 29, 2024, Metro released the final environmental impact report (EIR), awaiting board approval. The Federal Transit Administration's decision is expected by summer 2024. Subsequently, on April 25, 2024, the board certified the EIR, clearing the way for construction to begin by year-end. Immediately thereafter, Metro issued an RFP to select a contractor for pre-construction "Advanced Works."
In October 2024, the California State Transportation Agency (CalSTA) granted Metro $231 million toward building the Southeast Gateway Line as part of the $1.3 billion Transit and Intercity Rail Capital Program Cycle 7. Groundbreaking for preliminary utility relocations commenced on October 31, 2024.
Proposed routings and modes
The Southeast Gateway Line is envisioned as a 19.3 mi light rail corridor linking downtown Los Angeles with Artesia, serving communities such as Vernon, Huntington Park, Bell, Cudahy, South Gate, Downey, Paramount, Bellflower, and Cerritos.
South of Slauson Avenue, the route diverges from the A Line corridor via the former Pacific Electric Whittier Line, proceeding south adjacent to Union Pacific Railroad's San Pedro Subdivision before following the historic Santa Ana right-of-way beyond Paramount/Rosecrans.
The northern segment through Downtown Los Angeles is under evaluation as a possible subterranean light rail alignment with six alternatives proposed. As of 2018, two primary options were under consideration; both connect with the southern segment by running parallel to the A Line between and stations and utilize an existing freight rail corridor along Randolph Street:
- Alameda Street (Alternative E): A subway beneath Alameda Street through the Arts District linking with both the A and E lines at , continuing onward to .
- Downtown Transit Core (Alternative G): This option veers west from Alameda within the Arts District and proceeds underground through downtown Los Angeles, terminating at either or .
By March 2018, Cerritos withdrew its participation from the project, designating Pioneer Station as its southern terminus. In November that year, Metro excluded A Line stations north of Slauson from study boundaries to minimize overlap and enhance travel efficiency.
In 2019, Metro proposed dividing construction into two phases: an initial $1 billion segment linking Pioneer Station in Artesia to Slauson Station on the A Line; followed by a $3 billion extension reaching downtown as Phase 2. The agency expressed confidence that Phase 1 could be completed by 2028 utilizing Measure M funds while exploring public–private partnerships to expedite progress. Operational limitations mean that service will not interline with the A Line all the way to 7th Street/Metro Center station.
Route Selection: Alternative E
In 2022, the Metro Board confirmed Union Station as the northern endpoint. Construction for the section south of Slauson is planned to start in 2025, aiming for a 2035 launch. Completion of the northern stretch extending to Union Station is anticipated no earlier than 2043.
Stations
| Phase | Projected completion |
Station | Location | Connecting services | |
|---|---|---|---|---|---|
| 2 | 2043 | Template:LAMs | Downtown Los Angeles | Template:LACMTA icon strip Template:RintAmtrak, Template:Rint LAX FlyAway, Template:Rint Metrolink Paid parking: 3,000 spaces | |
| Template:LAMs | Little Tokyo, Los Angeles | Template:LACMTA icon strip | |||
| Arts/Industrial District | Arts District, Los Angeles | ||||
| 1 | 2035 | Template:LAMs | Florence-Graham, California | Template:LACMTA icon | |
| Pacific/Randolph | Huntington Park, California/Walnut Park, California | ||||
| Florence/Salt Lake | Bell, California/Cudahy, California | ||||
| Firestone | South Gate, California | ||||
| Gardendale | Downey, California | ||||
| I-105/C Line | Paramount, California | Template:LACMTA icon | |||
| Template:Stn | |||||
| Template:Stn | Bellflower, California | ||||
| Template:Stn | Artesia, California | ||||
Proposed Rio Hondo Confluence Station
Metro is exploring the addition of a station at the junction of the Los Angeles River and Rio Hondo in South Gate, California. This station would facilitate anticipated growth within the vicinity.
Proposed Cerritos Station(s) and Orange County Extension
An optional station located at Bloomfield Avenue in Cerritos, California, just north of the boundary between Los Angeles and Orange counties, is under consideration by Metro to support a future extension into Orange County. This extension would integrate with the ongoing OC Streetcar project, which utilizes part of the Pacific Electric WSAB corridor.
Following the election of Mayor Frank Yokoyama and councilmembers favoring station development in April 2025, Cerritos City Council began discussions with Metro. On May 2, 2025, Cerritos submitted a letter of intent to explore potential station locations. The city reviewed an informational briefing on the Southeast Gateway Line during its May 22 meeting. Subsequently, on June 26, 2025, Cerritos authorized a $127,000 contract with Cityworks Design—an entity experienced with Metro’s Southeast Gateway Line—to conduct a six-month study starting in July 2025 to identify suitable station sites. In parallel, Cerritos staff is organizing a joint session with Metro and the Orange County Transportation Authority (OCTA) to examine extending the Southeast Gateway Line into Orange County.