The Altamont Corridor Express (also known as ACE, formerly Altamont Commuter Express) is a
commuter rail
Commuter rail, or suburban rail, is a passenger rail transport service that primarily operates within a metropolitan area, connecting Commuting, commuters to a Downtown, central city from adjacent suburbs or commuter towns. Generally commuter r ...
service in
California
California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the m ...
, connecting
Stockton and
San Jose during peak hours only. ACE is named for the
Altamont Pass
Altamont Pass, formerly Livermore Pass, is a low mountain pass in the Diablo Range of Northern California between Livermore in the Livermore Valley and Tracy in the San Joaquin Valley. The name is actually applied to two distinct but nearby ...
, through which it runs.
Service is managed by the San Joaquin Regional Rail Commission, and operations are contracted to Herzog Transit Services.
The route includes ten stops, with travel time about 2 hours and 12 minutes end-to-end. In , the line had a ridership of , or about per weekday as of . ACE uses
Bombardier BiLevel Coach
The Bombardier BiLevel Coach is a bilevel passenger railcar currently built by Alstom and previously by Bombardier, Hawker Siddeley Canada, the Canadian Car and Foundry (Can Car), and the UTDC. Used by North American commuter rail operators ...
es,
MPI F40PH-3C locomotives, and
Siemens Charger
The Siemens Charger is a family of diesel-electric passenger locomotives designed and manufactured by Siemens Mobility for the North American market.
There are five variants of the Charger, tailored for different operators and types of service ...
locomotives.
Service began on October 19, 1998, with two weekday round trips. A third round trip was added in May 2001, followed by a fourth round trip in October 2012. Saturday service commenced in September 2019. , average weekday ridership is 5,900.
The tracks are owned by
Union Pacific Railroad
The Union Pacific Railroad , legally Union Pacific Railroad Company and often called simply Union Pacific, is a freight-hauling railroad that operates 8,300 locomotives over routes in 23 U.S. states west of Chicago and New Orleans. Union Paci ...
, previously built along the
Western Pacific Railroad
The Western Pacific Railroad was a Class I railroad in the United States. It was formed in 1903 as an attempt to break the near-monopoly the Southern Pacific Railroad had on rail service into northern California. WP's Feather River Route dire ...
main line. Under the ACE''forward'' program, a number of improvements to the service are being considered. These include a rerouted line through Tracy, an extension to
Modesto
Modesto () is the county seat and largest city of Stanislaus County, California, United States. With a population of 218,464 at the 2020 census, it is the 19th largest city in the state of California and forms part of the Sacramento-Stockton ...
and
Merced
Merced (; Spanish for "Mercy") is a city in, and the county seat of, Merced County, California, United States, in the San Joaquin Valley. As of the 2020 Census, the city had a population of 86,333, up from 78,958 in 2010. Incorporated on April 1 ...
, and connections to BART at Union City and Tri-Valley.
History and funding
Planning
By the 1980s, three rapidly growing areas in California –
Silicon Valley
Silicon Valley is a region in Northern California that serves as a global center for high technology and innovation. Located in the southern part of the San Francisco Bay Area, it corresponds roughly to the geographical areas San Mateo Coun ...
, the
Tri-Valley
The Tri-Valley area is grouping of three valleys in the East Bay region of California's Bay Area. The three valleys are Amador Valley, San Ramon Valley, and Livermore Valley. The Tri-Valley encompasses the cities of Dublin, Livermore, Pleasa ...
, and the
San Joaquin Valley
The San Joaquin Valley ( ; es, Valle de San Joaquín) is the area of the Central Valley of the U.S. state of California that lies south of the Sacramento–San Joaquin River Delta and is drained by the San Joaquin River. It comprises seven ...
– were poorly connected by public transit, as
Interstate 580 and
Interstate 680 became more congested. Commuting from the San Joaquin Valley or the Tri-Valley to Silicon Valley required using a car or limited bus service.
In 1989, the San Joaquin Council of Governments, Stockton Chamber of Commerce, and the Building Industry Association of the Delta started work on a 20-year transportation plan for the northern section of the San Joaquin Valley. In November 1990,
San Joaquin County
San Joaquin County (; Spanish: ''San Joaquín'', meaning " St. Joachim"), officially the County of San Joaquin, is a county in the U.S. state of California. As of the 2020 census, the population was 779,233. The county seat is Stockton.
San ...
voters passed Measure K, a half-cent sales tax to fund a variety of transportation improvements.
The highest-priority project was the establishment of passenger rail service to San Jose.
![Altamont Commuter Express (logo)](https://upload.wikimedia.org/wikipedia/commons/8/86/Altamont_Commuter_Express_%28logo%29.png)
In 1995, San Joaquin County and seven cities along the route formed the San Joaquin Regional Rail Commission (SJRRC) to oversee the creation of the service.
In May 1997, the Altamont Commuter Express Joint Powers Authority (ACE JPA) was formed by the SJRRC,
Santa Clara Valley Transportation Authority
The Santa Clara Valley Transportation Authority, more commonly known simply as the Valley Transportation Authority (VTA), is a Special district (United States), special district responsible for public transit services, Congestion management agenc ...
(VTA), and Alameda Congestion Management Agency (ACMA). That agreement formalized financial support, administrative processes, and governance for the rail service.
The operation is funded by a variety of state and federal sources, largely sales tax revenue collected by the three JPA signatories, while farebox revenues account for about one-third of costs.
Cost sharing for capital projects, excluding stations, during the initial 36 months of service was determined by the JPA on a case-by-case basis and approved by each of the member agencies. The initial purchase of rolling stock, construction of stations, and other start-up costs, amounting to some $48 million, were covered primarily by Measure K funds. Station improvements are the responsibility of the county in which the station is located. ACE pays the Union Pacific Railroad about $1.5 million per year to use their tracks. ACE trains also use about of Caltrain track in San Jose.
Service began on October 19, 1998, with two daily round trips running to San Jose in the morning and Stockton in the evening.
Service expansion
![Santa Clara station 0937 11](https://upload.wikimedia.org/wikipedia/commons/4/49/Santa_Clara_station_0937_11.JPG)
The original service used two trainsets, each with four bilevel coach cars, for a total seated capacity of 1,120 passengers in each direction daily. In September 1999, less than a year after opening, the service reached 1,000 daily riders per direction, near full capacity.
With that success, the agency wanted to add additional runs. To enable more trains on the line, ACE funded $3 million in track improvements, but the limited amount of equipment only allowed ACE to add a morning "
short turn
In public transport, a short turn, short working or turn-back is an earlier terminus on a bus or rail line that is used on some scheduled trips that do not operate along the full length of the route.
Short turns are practical in scheduling when t ...
" run between San Jose and Pleasanton. This "turn-back train" started service on February 21, 2000, and gave Pleasanton and Fremont a third inbound train to alleviate the crowding on the two earlier trains. Even with the added capacity, by early 2001 ACE was regularly carrying more than 700 daily standees.
ACE purchased additional equipment, allowing the "turn-back train" to operate to Lathrop/Manteca station, nearly the full length of the route, beginning on March 5, 2001; trains also began stopping at
Santa Clara station. Although the third train added 560 seats in each direction, it brought an immediate increase of 380 daily riders.
ACE then planned to add a fourth round trip later in the year, with fifth and sixth round trips by 2006.
However, by late 2001, the deepening
dot-com recession was severely hurting ridership, and expansion plans were put on hold. On June 30, 2003, the ACE JPA was dissolved in favor of a Cooperative Services Agreement between the three member agencies.
On January 6, 2003, ACE introduced the Stockton Solution Shuttle, allowing Stockton passengers to use the ACE trip which terminated at Lathrop/Manteca.
The trip was extended to Stockton on August 1, 2005. At that time, service to Santa Clara was suspended to allow for the construction of a second platform and pedestrian tunnel at the station.
On August 28, 2006, ACE added a fourth round trip, which operated midday using one of the existing trainsets.
On November 7, 2006, San Joaquin County voters approved a 20-year extension of Measure K.
Suffering from reducing funding due to the
Great Recession
The Great Recession was a period of marked general decline, i.e. a recession, observed in national economies globally that occurred from late 2007 into 2009. The scale and timing of the recession varied from country to country (see map). At ...
, ACE cut the lightly used midday trip on November 2, 2009.
On May 14, 2012, ACE restored service to Santa Clara station.
On October 1, 2012, a fourth rush-hour round trip was added, running approximately one hour after existing trips.
Altamont Corridor Express
![New ACE livery at Fremont-Centerville station, July 2018](https://upload.wikimedia.org/wikipedia/commons/0/04/New_ACE_livery_at_Fremont-Centerville_station%2C_July_2018.JPG)
In December 2012, the service was rebranded from Altamont Commuter Express to Altamont Corridor Express to reflect plans for a broader scope of service.
In March 2014, ACE opened a $65 million, maintenance facility in Stockton. On July 1, 2015, management and governance of the ''San Joaquin'' passed from Caltrans to the new San Joaquin Joint Powers Authority. The SJJPA has nominal control over the SJRRC, but delegates all responsibility over ACE to the SJRRC.
On March 7, 2016, an ACE train was derailed by a mudslide in
Niles Canyon
Niles Canyon is a canyon in the San Francisco Bay Area formed by Alameda Creek, known for its heritage railroad and silent movie history. The canyon is largely in an unincorporated area of Alameda County, while the western portion of the cany ...
near
Sunol. The front car plunged into the rain-swollen
Alameda Creek. Fourteen passengers were injured, but there were no fatalities.
ACE received
Road Repair and Accountability Act
The Road Repair and Accountability Act of 2017 (Senate Bill 1), also known as the " Gas Tax", is a California legislative bill that was passed on April 6, 2017 with the aim of repairing roads, improving traffic safety, and expanding public tra ...
funds in order to initiate Saturday service in January 2018, with two Saturday round trips added in September 2019.
Future plans
In association with the
California High-Speed Rail
California High-Speed Rail (also known as CAHSR or CHSR) is a publicly funded high-speed rail system currently under construction in California in the United States. Planning for the project began in 1996, when the California Legislature and Gover ...
project, the ACE line is planned to be dramatically upgraded and expanded. Beginning around 2008, initial plans called for the Altamont Corridor Rail Project to produce a
high speed rail
High-speed rail (HSR) is a type of rail system that runs significantly faster than traditional rail, using an integrated system of specialised rolling stock and dedicated tracks. While there is no single standard that applies worldwide, lines ...
"Super ACE" capable of halving the travel time between the endpoints.
As the high-speed rail project was scaled back and rerouted to
Pacheco Pass
Pacheco Pass, elevation , is a low mountain pass located in the Diablo Range in southeastern Santa Clara County, California. It is the main route through the hills separating the Santa Clara Valley and the Central Valley.
As with most passes in ...
several years later, these plans were replaced with the more modest ACE''forward'' program. The San Joaquin Regional Rail Commission issued a notice of intent to proceed with an
Environmental Impact Statement in June 2013; this was released in 2017 and prioritized goals as either long term or short term.
Short term goals included track improvements, a possible reroute through downtown
Tracy including new stations, a West Tracy station, and a new extension to
Modesto
Modesto () is the county seat and largest city of Stanislaus County, California, United States. With a population of 218,464 at the 2020 census, it is the 19th largest city in the state of California and forms part of the Sacramento-Stockton ...
in addition to additional daily round trips. Long term goals included upgrades to the existing corridor to allow as many as 10 daily round trips, extension to
Merced
Merced (; Spanish for "Mercy") is a city in, and the county seat of, Merced County, California, United States, in the San Joaquin Valley. As of the 2020 Census, the city had a population of 86,333, up from 78,958 in 2010. Incorporated on April 1 ...
and
electrification
Electrification is the process of powering by electricity and, in many contexts, the introduction of such power by changing over from an earlier power source.
The broad meaning of the term, such as in the history of technology, economic histor ...
of the line from Stockton to San Jose.
Also under studied were possible connections with
BART
Bart is a masculine given name, usually a diminutive of Bartholomew, sometimes of Barton, Bartolomeo, etc.
Bart is a Dutch and Ashkenazi Jewish surname, and derives from the name ''Bartholomäus'', a German form of the biblical name ''Bartho ...
at
Union City or the
Tri-Valley
The Tri-Valley area is grouping of three valleys in the East Bay region of California's Bay Area. The three valleys are Amador Valley, San Ramon Valley, and Livermore Valley. The Tri-Valley encompasses the cities of Dublin, Livermore, Pleasa ...
via traditional ACE rail,
diesel multiple units, or bus bridges. This connection is planned to be facilitated by the
Tri-Valley-San Joaquin Valley Regional Rail Authority.
Altamont Corridor Vision
The state senate allocated $400 million in revenue from a
gas tax
A fuel tax (also known as a petrol, gasoline or gas tax, or as a fuel duty) is an excise tax imposed on the sale of fuel. In most countries the fuel tax is imposed on fuels which are intended for transportation. Fuels used to power agricultural v ...
increase to ACE''forward'' expansion.
ACE was awarded $500.5 million in April 2018 for expanded service to Ceres and Sacramento to provide more rail service and connections within the
Central Valley. Service is expected to begin from Ceres by 2023
with interim
bus bridge service to Merced until that segment of Union Pacific right-of-way is upgraded. Four trains will depart Ceres in the mornings, and one train may make the complete run to San Jose with others transferring passengers at North Lathrop.
By 2019, the plan had come to be called the Altamont Corridor Vision, with an expected price of $9.7 billion, allowing ACE to run up to six weekday round trips in 2023 with the goal of ten weekday round trips once additional track infrastructure is completed. ACE and the Tri-Valley-San Joaquin Valley Regional Rail Authority sought funding to construct a shared tunnel under Altamont pass in order to speed service and increase reliability. The Union Pacific right of way between Ceres and Lathrop will be
double tracked to facilitate passenger service.
platforms are being extended to accommodate longer trains.
Valley Rail
Valley Rail is the project to route ACE and Amtrak ''
San Joaquins
The ''San Joaquins'' is a passenger train service operated by Amtrak in California's San Joaquin Valley. Six daily round trips run between its southern terminus at Bakersfield and Stockton, with onward service to Sacramento (all round trips) an ...
'' along the little-used
Sacramento Subdivision between Stockton and Sacramento. Six new stations would be constructed along the line with a layover facility at Natomas. Trains would run the length of the line from Natomas to San Jose or Ceres with a midday
short turn
In public transport, a short turn, short working or turn-back is an earlier terminus on a bus or rail line that is used on some scheduled trips that do not operate along the full length of the route.
Short turns are practical in scheduling when t ...
to Stockton. A Draft Environmental Impact Statement was released in 2020, with services expected begin no later than 2023. The North Elk Grove station was eliminated from planning in September 2020.
Service
, ACE operates four round trips per weekday in the peak rush hour directions – westbound (to San Jose) in the morning and eastbound (to Stockton) in the evening. Trains are scheduled to make the one-way trip in 2 hours 12 minutes, an average speed of .
ACE did not operate on weekends or major holidays until September 7, 2019, when two Saturday round trips were added.
Route
![ACE EMD F40PH Fremont - San Jose](https://upload.wikimedia.org/wikipedia/commons/6/60/ACE_EMD_F40PH_Fremont_-_San_Jose.jpg)
From San Jose to just north of Santa Clara, ACE uses the
Caltrain
Caltrain (reporting mark JPBX) is a California commuter rail line serving the San Francisco Peninsula and Santa Clara Valley (Silicon Valley). The southern terminus is in San Jose at Tamien station with weekday rush hour service running as fa ...
main line (Peninsula Subdivision), shared with Caltrain and Amtrak service. From Santa Clara to Stockton – the majority of the route – ACE runs on
Union Pacific Railroad
The Union Pacific Railroad , legally Union Pacific Railroad Company and often called simply Union Pacific, is a freight-hauling railroad that operates 8,300 locomotives over routes in 23 U.S. states west of Chicago and New Orleans. Union Paci ...
freight lines. From Santa Clara to Newark, ACE uses the
Coast Subdivision, then the
Niles Subdivision to
Niles. From Niles to Lathrop, the line uses the
Oakland Subdivision
The Oakland Subdivision is a Union Pacific Railroad line in the U.S. state of California. It extends from Stockton in the east to Oakland, crossing the Diablo Range at Altamont Pass and traversing Niles Canyon. The line was originally built by the ...
.
From Lathrop to Stockton, the line uses the Fresno Subdivision.
The route runs through
Niles Canyon
Niles Canyon is a canyon in the San Francisco Bay Area formed by Alameda Creek, known for its heritage railroad and silent movie history. The canyon is largely in an unincorporated area of Alameda County, while the western portion of the cany ...
, parallel to the
Niles Canyon Railway
The Niles Canyon Railway (NCRy) is a heritage railway running on the first transcontinental railroad alignment (1866, 1869) through Niles Canyon, between Sunol and the Niles district of Fremont in the East Bay of the San Francisco Bay Area, ...
,
Highway 84, and the
Hetch Hetchy Aqueduct
Hetch Hetchy is a valley, a reservoir, and a water system in California in the United States. The glacial Hetch Hetchy Valley lies in the northwestern part of Yosemite National Park and is drained by the Tuolumne River. For thousands of years bef ...
. The line passes through a long tunnel which cuts off one of the canyon's horseshoes. This tunnel was modified from its original configuration to accommodate intermodal double-stack freight trains. However, this left the track in poor condition, reducing speeds from to in the summer and as low as during the rainy season. The San Joaquin Regional Rail Commission plans to rehabilitate the tunnel.
East of Pleasanton and Livermore, the line runs through the
Altamont Pass
Altamont Pass, formerly Livermore Pass, is a low mountain pass in the Diablo Range of Northern California between Livermore in the Livermore Valley and Tracy in the San Joaquin Valley. The name is actually applied to two distinct but nearby ...
on the original
Feather River Route
The Feather River Route is a rail line that was built and operated by the Western Pacific Railroad. It was constructed between 1906 and 1909, and connects the cities of Oakland, California, and Salt Lake City, Utah. The line was built to compet ...
. After crossing the
California Aqueduct
The Governor Edmund G. Brown California Aqueduct is a system of canals, tunnels, and pipelines that conveys water collected from the Sierra Nevada Mountains and valleys of Northern and Central California to Southern California. Named after Califo ...
and the
Delta-Mendota Canal into the
Central Valley, skirting the southern edge of
Tracy. It then turns north between Lathrop and Manteca and runs to
Robert J. Cabral Station in Stockton.
Tickets and fares
ACE tickets are available at select stations and on ACE's web site. Distance-based fares are available in one way, round trip, 20 trip, and monthly passes.
Rolling stock
![ACE train at Santa Clara station, September 2021](https://upload.wikimedia.org/wikipedia/commons/e/e5/ACE_train_at_Santa_Clara_station%2C_September_2021.jpg)
ACE operates
push-pull trains with one to two diesel locomotives and four to eight bilevel coach cars.
Trains typically operate with the locomotive(s) leading westbound and the cab car leading eastbound.
ACE has ordered 17 additional Bombardier BiLevel cars (5 cab cars and 12 coaches). Deliveries were expected to begin sometime in 2021. The entire fleet of Bombardier bilevel coach cars and MPI F40PH-3C locomotives will be rebuilt, overhauled, and repainted to have a matching paint scheme, except for two F40PH locomotives that were retired in May 2020. They will then continue to operate along with the newer Siemens Charger SC-44 locomotives, which entered service in 2020.
See also
*
List of San Francisco Bay Area trains
This is a list of trains and train museums in the San Francisco Bay Area of Northern California in the United States.Lists of San Francisco Bay Area rail related resources can often be found at the "Links" page of a club or museum website. Exam ...
References
External links
Official Altamont Corridor Express websiteACE''forward'' projectsSan Joaquin Regional Rail Commission website
{{Authority control
California railroads
Passenger rail transportation in California
Public transportation in the San Francisco Bay Area
Public transportation in the San Joaquin Valley Area
Public transportation in Alameda County, California
Public transportation in San Joaquin County, California
Public transportation in Santa Clara County, California
Transportation in San Jose, California
Diablo Range
Fremont, California
Livermore, California
Pleasanton, California
Santa Clara, California
Stockton, California
Tracy, California
Standard gauge railways in the United States
Commuter rail in the United States
Railway lines opened in 1998
1998 establishments in California
2023 in rail transport