Miami’s “Underline” — The Vision for a 10-Mile Greenway Beneath the Rails

The idea for Miami's "Underline" came to Meg Daly after she broke both her arms in 2013.

Unable to drive, Daly, who lives in Coral Gables, started taking Miami's Metrorail to physical therapy. When she got off at her stop, she would walk the last mile under the shade of the elevated rail platform.

"I just kind of had this moment of discovery," she told Streetsblog. "I ended up walking beneath the train tracks. I was like, 'There’s so much space here.'" She thought the neglected but nicely shaded area could make for great walking and biking.

Now, just a few years later, a real plan for a 10-mile linear park called the Underline is moving forward. Daly heads the nonprofit group Friends of the Underline, which is finishing up the master plan for the project. The group received $650,000 for planning and design, funded by the city of Miami, the Knight Foundation, the Miami Foundation, and others.

The Friends of the Underline vision is to create an inviting place for active transportation running through one of the most densely populated urban areas in the American South.

Miami's Metrorail corridor runs 10 miles between South Miami, Coral Gables, and Miami, terminating in the walkable Brickell neighborhood. The corridor roughly parallels US-1, a traffic-clogged urban highway that runs up the eastern coast of Florida.

About 100,000 people live within a 10-minute walk, Daly says. But active transportation options are limited, largely because of South Florida's notoriously wide, dangerous roads.

The key insight Daly had was that the space under the elevated Metrorail provides a potential respite. But right now it's very uninviting. The Underline project is all about making it safe and appealing for people.

Plans call for adding two trails -- one for walking, one for biking -- lighting, drinking fountains, play equipment, and seating. All the "things that make you want to bike and walk," said Daly.

They estimate the project will cost about $120 million. About $20 million of that would go toward redesigning intersections between city streets and the trails to minimize risks to walkers and bikers. That will be no small job. Lots of the feeder streets to US-1 dump traffic into through streets that cross the Underline's path.

"It’s all about the car," said Daly. "All the intersections are designed to favor automotive travel."

Daly says potential conflicts will be managed in a number of ways. At some intersections, the trail crossing will be highlighted with colored paint to urge caution for drivers. Many intersections will have a full signal phase solely for bicyclists and pedestrians. In a few of the most difficult cases, the trail will be elevated above the cross street on accessible bridges.

Daly says development is already springing up along the path of the project, but the nonprofit is still seeking funding to realize its vision. Friends of the Underline hopes to win grants from the Florida Department of Transportation and the federal government. And to fund maintenance, the organization plans to use a special assessment that would capture increased property tax revenue from nearby development.

"What we’re really all about is promoting development by transit which is an new idea down here," she said.