CA: The world's longest light-rail line connects LA suburbs to the past

Before the railroad came to town, San Dimas was known as a swampy pit of mud — the Los Angeles-area community's name in the early 1800s was literally Mud Springs. That changed with the completion of the Santa Fe Railroad in 1887. The new train sparked a land boom in the community and enabled its transformation into an agricultural powerhouse, shipping citrus fruits all over the world. Eventually, those citrus orchards paved the way for development, and a growing San Dimas incorporated in 1960, though it held tight to its rural charms and Old West aesthetic.

But for decades, San Dimas — now a suburban foothill community of around 33,000 residents — has been a railroad town without any train service. Southern California's once expansive Pacific Electric Railway (also known as Red Cars) stopped running in 1951 for San Dimas and neighboring communities, marking the end of local rail service in the area, and the historic Santa Fe Railroad Depot that had first transformed the mudflat closed a decade later. Today, the yellow Art Deco building that commuters pass by in their cars is a museum dedicated to the Pacific Railroad.

But now, after nearly 75 years, San Dimas and its neighbors finally have rail service again — and along a record-breaking rail line, at that. On Friday, Sept. 19, the Los Angeles County Metropolitan Transportation Authority (aka LA Metro) debuted its long-awaited A Line extension, adding stops in Glendora, San Dimas, La Verne and Pomona. Even before the new 9-mile addition, the A Line (previously known as the Gold Line) was the longest light-rail line in the world. It's now even longer, spanning approximately 58 unbroken miles from Pomona to the Long Beach coastline.

Connecting Long Beach and Pomona, two of Los Angeles County's largest cities, is a massive feat in the giant county, which spans 4,084 square miles, nearly 100 times the size of San Francisco.

With the new extension, county residents can now travel between the two cities for just $1.75 on trains that run roughly every 8 minutes. People in inland Los Angeles County can take the light-rail to the beach; people living in Los Angeles proper can commute out to universities in La Verne, Claremont and Pomona. The new extension also provides access to Raging Waters in San Dimas, said to be the state's largest water park, and to Fairplex in Pomona, home to the annual LA County Fair.

The newly elongated A Line is a giant step forward for LA County's transportation infrastructure. But it's also in many ways a step into the past, bringing back long-severed rail connections between the region's suburbs and its urban core.

Similar to San Dimas, all four of the communities now reconnected to the region's passenger trains started out as boom towns along the railroads of the late 1800s and later developed into new suburbs with the help of the Pacific Electric Railway, which shuttled residents to and from Los Angeles and beyond. Then, those rail connections disappeared.

Pomona is the only one of the four suburbs that already had passenger rail before the A Line extension. Metrolink's San Bernardino Line, a regional commuter line, serves the city's Pomona North station, and its Riverside Line serves downtown Pomona. Amtrak's long-distance Sunset Limited route also stops at the downtown Pomona station.

The new A Line connection at Pomona North means riders coming from the Inland Empire on Metrolink's San Bernardino Line can now easily connect with the A Line for service to foothill communities like Pasadena, "making it possible for the first time since the era of the streetcars to take trains between the San Gabriel Valley's Foothill Cities and the Inland Empire," according to LA Metro.

Much of LA County's old rail infrastructure was abandoned by passenger trains just as the region's car dependence was taking off, jump-starting the region's pervasive freeway system. Today, a transit fan enjoying the full length of the roughly 58-mile A Line train would have to allot little over two hours, while typical (non-rush hour) drive times between Pomona and Long Beach are closer to an hour. Still, most riders won't be traveling the full route but taking point-to-point trips along the line, which at certain times can offer quicker travel times than driving. My ride to San Dimas from northeast Los Angeles on the extension's opening day took around 50 minutes, while Google Maps projected that driving the same distance at that time would be around 49 minutes. At peak after-work commuting hours, that same trip could take 90 minutes or even longer by car.

At Friday's A Line extension opening, the new era of connectivity for the four suburban communities was celebrated with much fanfare. Each of the four stops was packed with riders, many of whom were hopping on just for fun or just to travel one stop away. Opening day festivities featured afternoon DJ sets at each station, and rides on the Metro A Line were free all weekend.

The hope, from LA Metro at least, is that the celebratory momentum will continue, with more people opting to ditch the congested freeways for the light-rail system. LA Metro, similar to other transit agencies across the country, is still struggling to return to prepandemic ridership numbers. Last year, the agency (which also operates area buses) saw more than 311 million boardings, marking the first time LA Metro had surpassed 300 million boardings since 2019.

The extension is just the latest phase of a decades-long effort to connect Los Angeles to the foothill communities stretching east along Interstate 210, along which hundreds of thousands of people commute daily. Phase 1 of the A Line, stretching from Union Station in downtown Los Angeles to Pasadena, opened in 2003, and Phase 2A from Pasadena to Azusa added six new stations that opened in 2015. This latest extension connects Azusa to the Pomona North station, which won't be the end of the line for the world's longest light-rail — one more planned extension is expected to cross into San Bernardino County and make Montclair the terminal station.

Today, parts of the A Line train run right in the middle of Interstate 210, allowing train riders to look directly out at the traffic congestion they've escaped — and allowing drivers in stop-and-go traffic to eye the train as it steadily zooms ahead.

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