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Los Angeles is often described as a concrete jungle, a city shaped by asphalt, parking lots and other hardscape. Now, for the first time, researchers have mapped that concrete in detail, and they claim a lot of it doesn’t need to be there.
A new analysis finds that some 44% of Los Angeles County’s 312,000 acres of pavement may not be essential for roads, sidewalks or parking, and could be reconsidered.
The report, DepaveLA, is the first parcel-level analysis to map all paved surfaces across L.A. County, and to distinguish streets, sidewalks, private properties, and other areas. The researchers divided all pavement into “core” and “non-core” uses. A street, for example, is core. Then they paired that map with data on heat, flooding and tree canopy, creating what they intend as a new framework for understanding where removing concrete and asphalt could make the biggest difference for people’s health and the climate.
Paved surfaces get hotter than those with plantings, absorbing and radiating out the sun’s energy rather than converting it into plant growth, which in turn creates shade. Hotter areas also create more ozone smog. Greener areas are known to bring people psychological relief as well.
The authors are the nonprofit Accelerate Resilience L.A., founded by Andy Lipkis, who also founded TreePeople, the Los Angeles tree planting organization, and Hyphae Design Laboratory, a nonprofit that works to bridge health and the built environment.
What surprised them most, said Brent Bucknum, founder of Hyphae, was seeing where the pavement is concentrated. Nearly 70% of what they deemed non-core pavement is on private property.
Rather than a sweeping removal of pavement, the report highlights small changes that could add up.
The most potential they found was in parking areas, especially large, privately owned commercial and industrial lots. Redesigning 90-degree parking into angled parking could get rid of up to 1,600 acres, creating room for trees and stormwater capture, without reducing the number of parking spaces.
Parking lots, Bucknum said, are one of the clearest examples of how excess pavement has become accepted, even as it makes everyday life worse for residents.
“I’m often amazed — I’ll drive into a parking lot and there’s beeping, bumper-to-bumper traffic, you’re under this sweltering heat trying to get out of the grocery store,” he said. “And the reality is, we can make it a lot nicer with more thoughtful design.”
Ben Stapleton, chief executive officer of the U.S. Green Building Council California, pointed to parking requirements that long tied the number of spaces to a building’s size and use.
“The natural solution was to just pave things over, because it’s cheaper, it’s less maintenance,” he said. “It’s not very expensive, especially asphalt.”
Residential property, including apartment complexes, are another place with potential.
If each residential parcel cut a 6-by-6-foot tree well in their patio, Bucknum said, it would amount to 1,530 acres of pavement removed, while on average only reducing patio space by 3%.
Emily Tyrer, director of green infrastructure at TreePeople, said pavement is expanding in residential yards.
“What we’re seeing is that a lot of residential yards are moving toward more paving and less lawn,” she said. “Rather than replacing it with shade trees and native plantings and low water use plants, they’re paving over.”
In many cases, she said, homeowners are responding to drought messaging and rising water costs.
“Paving does reduce water use, and it can reduce people’s water bills,” Tyrer said. “But it comes with trade-offs.”
The report also identifies schools as places where there could be less concrete or asphalt. On average, school campuses across L.A. County are approximately 40% covered in pavement, leaving students exposed to extreme heat.
At Esperanza Elementary School, near downtown Los Angeles, the campus was “just a sea of asphalt,” said Tori Kjer, executive director of the Los Angeles Neighborhood Land Trust, which is overseeing a transformation at the school. Children ran across blacktop that could reach over 120 degrees on warm days.
It will soon have new California native plants and shade trees, stormwater capture features, grassy lawn, natural play elements, outdoor classrooms and more.
Many of the school families live in small apartments.
“People don’t have any open space,” Kjer said. “They leave their home, and they’re basically just on concrete streets and sidewalks.” Once the asphalt is removed and the trees go in, and rainwater is guided away, it will be a “place for quiet, imaginative play and active play.”
The idea for the Depave report grew out of years of work on tree planting and green infrastructure projects that repeatedly ran into the same barrier.
On project after project, pavement emerged as the central problem, according to Bucknum. “We were trying to plant trees, but so much of the city is paved that there was nowhere to put them,” he said.
The team realized they needed better data to understand the problem, down to the block and neighborhood scale. Something more sophisticated than what is pavement and what is trees.
“This is a first step,” said Devon Provo, senior manager, planning and program alignment at Accelerate Resilience L.A. “It’s an opportunity assessment, not a prescriptive plan for what should 100% be removed.”
Olivier Sommerhalder, a principal and global sustainability leader at the design and planning firm Gensler, pointed out businesses that have paid out the money to pave something would need an upside to replace it.
“There are no incentives for property owners to reduce hardscape,” Sommerhalder said. “The municipality does not incentivize the removal of parking to mitigate urban heat hot spots.”
Sommerhalder said sustainability is increasingly part of design conversations with clients, particularly as tenants ask about comfort and environmental performance. But without policy or financial incentives, he said, surface parking often remains untouched until redevelopment.
As for what an incentive might look like, “we think a really good analogy is the lawn replacement program,” Bucknum said, referring to rebate programs that helped shift Southern California away from water-intensive turf. “People didn’t know there were other options until there was education and financial support.”
It’s important to take into account what is underneath the pavement, said Carlos Moran, executive director of North East Trees, especially in areas with industrial histories.
In some neighborhoods, he said, pavement caps contaminated soil that cannot safely be disturbed. “We can’t just rip it out.”
But he agreed there’s too much pavement. “The hottest blocks in Los Angeles, they’re not just lacking trees,” he said. “They’re overbuilt with asphalt.”
The goal of the report, Provo said, is to give Angelenos and decision-makers a shared starting point for conversation.
“This data is relevant to anyone who wants to have a say in reimagining the future of Los Angeles to be cooler, healthier and more vibrant,” Provo said.
“My hope is that it opens the eyes of people who are building projects who may not have ever even thought about pavement in this way,” Stapleton said. “Once you learn something, you don’t unlearn it.”
By reframing pavement as a design choice rather than a default, Stapleton believes that the analysis could prompt developers and property owners to rethink how much concrete their projects really need, and what they might gain by replacing it.
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Particulate matter (PM) samples of PM10 (smaller than 10 micrometers) and PM2.5 (smaller than 2.5 micrometers) were taken at Torgauer Street in Leipzig using two high-volume samplers, as are otherwise used at air monitoring stations in accordance with European standards. Credit: Ankush Kaushik, TROPOS
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