Michael Maltzan's Sixth Street Viaduct
Michael Maltzan's Sixth Street Viaduct
Credit: Michael Maltzan Architecture
Speculative urbanism: That’s the phrase that Los Angeles architect Michael Maltzan, FAIA, uses to describe the decades-long effort that has recast and revived the L.A. River. A concrete-lined drainage ditch for much of its 51-mile length, the river has nonetheless been celebrated by its boosters as the organizing device that will reinvent this ultimate decentralized city for the 21st century. A radically updated Los Angeles, long connected (and torn asunder) by freeways, will instead be tied together by verdant riverside promenades, bike paths, and an extended string of waterfront parks. The concept has the transformative potential of New York’s High Line, except that the L.A. River, stretching from Canoga Park in the San Fernando Valley to the Pacific Ocean in Long Beach, is 35 times longer.
Maltzan, for the moment, is the architect whose impact on the river is most conspicuous. His recently completed One Santa Fe on the fringe of downtown L.A. is a skinny apartment complex with two extremely long side-by-side buildings, elevated above levels of parking and open-air plazas, that extend for over a quarter mile on a site parallel to the river. Completed last year, the project houses 438 market-rate rental units directly across the street from SCI-Arc, in a neighborhood—the Arts District—that, despite its close proximity to Skid Row, is gentrifying at a breakneck pace. You can get a glimpse of the river from many of the complex’s east-facing apartments, but the view is mostly dominated by the railroad tracks—a half dozen at least—that run along the water.
Credit: Michael Maltzan Architecture
One Santa Fe
One Santa Fe
Credit: Iwan Baan
Early in the planning process, Maltzan partnered with a local organization called Friends of the L.A. River (FOLAR) to brainstorm a way for residents and the general public to access the river. Together they drew up a quartet of landscaped overpasses, erratically angular and layered with flowers. The pedestrian bridges are sadly unrealized; they were never intended to be more than just concepts. But Maltzan believes that the very act of visualization drives things forward: “The more images of what those connections could look like, the more that it’s possible for people who have the real power to effect those changes,” he says. “They have something to fight for, something to point to.”
Incrementally, up and down the river, highly speculative visions are being realized. A master plan that L.A. adopted in 2007 calls for a series of revitalization projects along the 31 miles of the river within city limits. Bits and pieces, formerly fenced in, have been turned into pocket parks, including one at the river’s headwaters in Canoga Park and several in surprisingly pastoral Glendale Narrows, where snowy egrets wade, indifferent to the noise from the nearby freeway. Last May, the Army Corps of Engineers—the federal entity that more or less owns the river—approved a $1 billion plan called Alternative 20, which aims to convert 11 miles just north of downtown into something approximating nature by removing the concrete, widening the river, creating wildlife-friendly wetlands, and adding access points. Federal and local governments would fund it jointly. And in January, the city debuted an Enhanced Infrastructure Financing District, which would allow property tax dollars to fund river improvements. Los Angeles Mayor Eric Garcetti is a major supporter of these efforts. “In some ways, the river is the city’s backbone,” he tells me. “It really is one of the few connecting things in what has been a disconnected city.”
“Los Angeles Riverscape: an Urban Estuary” rendering by Tina Chee from CSAO Architects
“Los Angeles Riverscape: an Urban Estuary” rendering by Tina Chee from CSAO Architects
Credit: Tina Chee
The river was once a meandering, wild stream that covered much of western L.A. with impassable, jungle-like wetland. It was often dry and, in many places, invisible, but was also prone to catastrophic floods. In the 1930s, Congress funded the Army Corps of Engineers’ effort to “channelize” the river. The unpredictable waterway was contained in a concrete culvert and was quickly hemmed in by industry, freeways, and modest neighborhoods. It was largely forgotten—until speculative urbanism, in the form of a poet named Lewis MacAdams, rediscovered it.
“Poetry and politics has always been the cusp I’ve operated on,” MacAdams, a stately presence topped by a pork-pie hat, told me recently. We were chatting at FOLAR’s office at the River Center, a hub for nonprofits. Now 80, MacAdams came to L.A. from Northern California in the 1970s and began writing for a small, eccentric magazine: WET: The Magazine of Gourmet Bathing. Suffice it to say he was probably thinking more deeply about water than the average Angeleno. He recalls walking to a bus stop and catching his first glimpse of the river. Somehow it became his obsession, his life’s work. In 1985, he staged a performance piece called Friends of the L.A. River. “I borrowed a set of wire cutters,” MacAdams recalls, “cut a hole in the fence, and declared the river open.”
A year later, MacAdams founded FOLAR, which now has eight employees, a $1 million annual budget, and a riverfront café, the Frog Spot. MacAdams has a gift for describing the river’s inherent contradictions: “I call it the postmodern river, a collaboration between humans and nature,” he says.
It’s not just the concrete he’s talking about. For much of the year, the water that flows between the banks is reclaimed from sewage treatment plants rather than coming from the river’s more pristine source in the Santa Monica Mountains. But his goal has always been simple: “I thought all I had to do was convince people that the river could be a beautiful place.”
A before-and-after rendering of the river by Tetra Tec, Civitas, Mia Lehrer, and Wenk Associates

While the river’s revitalization has been a collective effort, MacAdams has been singularly pivotal. He was Mayor Garcetti’s high school creative-writing teacher. And his La Gran Limpieza, an annual cleanup, was where landscape architect Mia Lehrer first encountered the river 20 years ago. Wiry and hyperkinetic, Lehrer simply thought the event would be good for her “rambunctious” son. Then the river became her passion. Lehrer’s term for what she and her colleagues have been up to all these years: “a guerrilla planning activity.”
Lehrer has been one of the most prolific creators of ideas that change the way the public and political culture regard the city. “The river,” says Lehrer, “is this gash, this linear infrastructure element.” Revitalizing it, she says, “is solving a lot of problems,” such as L.A.’s limited supply of parkland and water. And, she says, “It allows the city to get sewn back together.”
Lehrer was a key player in creating the city’s 2007 L.A. River Master Plan. She also helped influence the 2008 River Improvement Overlay District, which imposes development guidelines on land adjacent to the river: complete streets that are pedestrian and cyclist friendly, for instance, and landscaping that incorporates bioswales and green roofs. Every time kayakers paddle through the new Glendale Narrows recreation zone, they’re bringing to life the river that has thrived in her mind’s eye for decades.
Credit: Los Angeles Bureau of Engineering
Lehrer gives me a tour of riverfront neighborhoods featuring funky old warehouses, slick multimillion-dollar townhouses, and new microbreweries, a familiar template for urban transformation. She points out the spot in Atwater Village where a cable-stayed bridge, the La Kretz Crossing, will soon carry pedestrians, bikes, and equestrians across the river to Griffith Park. The donor of more than half the projected $9.6 million cost of the bridge, developer Morton La Kretz, has also announced his intention to build 60 townhouses on industrial land he owns nearby. This sort of mixture of altruism and opportunism is typical along the river; community activists warn that its rising profile has inspired a land grab. Mayor Garcetti says there’s been a 21 percent year-over-year increase in real estate values in river-adjacent Elysian Valley (as opposed to 16 percent in L.A. as a whole).
But developer Mott Smith of Civic Enterprise, a firm devoted to infill projects that has been buying properties near the river, has a different theory. “I don’t know that anyone has done any analysis to look at how differently the market is responding in river-adjacent areas than it is in other parts of the city that are relatively central and close to transit,” he says. “I actually think that the proximity to downtown and to walkable neighborhoods is actually the most important influencer right now in real estate.”
In other words, Smith is suggesting that the river boosters might have it backwards. Land isn’t becoming more valuable because of their success at reimagining the river. Instead, the river has become a cause célèbre because it’s in a part of town, long neglected, that’s increasingly desirable to home buyers who have been priced out of nearby Silverlake, for instance. Either way, the river has inspired planners, designers, and politicians to think big.
Take, for example, the Piggyback Yard Feasibility Study. From 2005 to 2010, Lehrer, MacAdams, and Maltzan, along with Perkins+Will and Silverlake-based Chee Salette Architecture Office, conspired to rethink a 130-acre Union Pacific freight yard on the river’s east side, just opposite downtown L.A. “We would meet every Friday, as if it were a real project,” Lehrer recalls. The idea was to redevelop the property for an arts school campus, workforce housing, and parkland that the river could harmlessly flood. The project intended to shift the center of L.A. eastward towards the revitalized Union Station and high-speed rail lines. Renderings on Chee Salette’s website show a dreamy, lush place, lined with translucent white towers and pedestrians everywhere, much like the L.A. depicted in the Spike Jonze movie Her.
Piggyback Yard
Piggyback Yard
Credit: PBy Collaborative Design Group
The Piggyback Yard plan is a lovely example of speculative urbanism, but it’s still unclear whether Union Pacific intends to sell the land to the city. Until then, the most profound and least speculative river-related project remains Maltzan’s Sixth Street Viaduct, scheduled for completion in 2019. The original Sixth Street Bridge, an Art Deco landmark built in 1932, was the largest concrete bridge in California prior to World War II. But the concrete, with its high alkali content, is plagued by what Maltzan calls “concrete cancer.”
“The original plans for the bridge were to basically tear it down and build a highway-style bridge,” says Maltzan. After community activists pushed for something more, he teamed up with engineers at HNTB, landscape architects at Hargreaves Associates, and urban designer A.C. Martin. The team’s winning entry in a 2012 design competition features a 3,500-foot-long series of spans supported by looping arches that appear to be skipping across the landscape. The structure carries cars across the river and rail yards, but it also has multilevel paths and ramps for pedestrians and bikers and, below, large soccer fields and public plazas. “Infrastructure,” says Maltzan, “doesn’t have to be a separator. It can be a destination.”
“If you look at iconic structures in other cities, like the Eiffel Tower or the Statue of Liberty, what they really do is they’re observatories,” Maltzan says. “You look out.” So this bridge has “climbing arches,” which are outfitted with stairways that will allow pedestrians to stand well above the roadway. Of course, there are already bridges in downtown L.A. with splendid views of the manmade river, which originally captured MacAdams’ imagination. It is an extraordinary object, the sort of thing that Charles Sheeler would have happily painted. But the view from the new bridge will likely be different: less concrete, more greenery. The viaduct’s arches will be the best spot in the city to see the reinvented river that pulls everything together.
Sixth Street Viaduct
Sixth Street Viaduct
Credit: Michael Maltzan Architecture