As a bartender at Mugs Alehouse, a wood-paneled tavern in Brooklyn’s Williamsburg neighborhood known for its great beer list, Andrew Lynch spends many shifts chatting with customers about the impending L train shutdown. The bar sits three blocks from the Bedford Avenue station, into which, come April 2019, no subway cars will run for 15 months as the city repairs a tunnel damaged in 2012 by Hurricane Sandy. How will Brooklynites get into Manhattan? This question has triggered a sense of looming doom across northern Brooklyn and the rest of the city. But Lynch thinks about it particularly fiercely: The bartender sunlights as a self-described “radical cartographer,” dreaming up enthralling renderings of transit systems in New York, Boston, and beyond. And he thinks he knows just the way to mitigate the shutdown.

Lynch, who creates ambitious visions of a future New York City subway system, is deeply familiar with the history of the biggest metro system in the country. He knows, for instance, that before the Great Depression hit, New York City had planned to expand subway service in northern Brooklyn, and even built a massive six-track station on top of what is now the Broadway G train stop to accommodate new train lines. That station hasn’t ever been used, except for the occasional rogue art project. So, Lynch thought: Why not create a new transfer hub there, between the G, J, M, and Z lines, streamlining trips for residents coming into and out of the Williamsburg neighborhood?

Lynch argues the move could help New York move even after the work is done and the tunnel is repaired. “This isn’t just some mitigation program,” he says. “This is something that would improve connectivity all over northern Brooklyn.”

The bartender/cartographer is one of many designers, safe streets advocates, and armchair subway enthusiasts who, in the face of the impending L train shutdown, are playing around with ideas to solve transportation problems typically left to city and state agencies. Some have pitched running gondolas, pontoon bridges, or inflatable tunnels across the East River. Others have proposed wringing more utility out of the existing subway network. Still others have suggested something unprecedented, at least in the US: banning private vehicles from the streets that the L would typically cover.

Many of the fantasies for mitigating the L train shutdown will remain just that. But fantasies have also catalyzed the development of technologies like hyperloops and self-driving cars. Maybe it’s the exact sort of thinking that New York City—not to mention the rest of the nation—needs.

The proposals range from the truly bizarre to the eminently reasonable. The most notorious one is probably the pontoon bridge. Last month, Parker Shinn, a real estate investor who left New York for San Francisco over three years ago, started getting attention for his Kickstarter seeking to raise $50,000 to fund a floating bridge across the East River. (It’s raised just under $11,000 to date.) Despite his skeptics, Shinn says he thinks his idea is “the only practical way” to mitigate the shutdown. But he admits that “you’d probably want something else as a long-term solution” beyond those 15 months.

A years-old proposal for a ski lift-style gondola across the East River has also seen renewed interest since the news broke about the L. In fact, it now bills itself as “the only practical way to increase capacity across the East River” by the time the shutdown rolls around. (Surprisingly, lot of inventive infrastructure proponents see “practicality” as a selling point.) Not long after the shutdown was announced, several local politicians wrote a letter voicing their support for the “East River Skyway,” but the project doesn’t yet have the funding or political support to build it in time.

Other proposals, like Lynch’s idea, reuse existing infrastructure. ReThink Studio, a design firm and consultancy, has suggested a massive extension of the E train, radically changing the way Brooklynites get to Manhattan (and vice versa) by sending the line down tracks currently used by other trains to form a perfect loop. It’s a big departure from the NYC subway’s normal routing—but in the opinion of ReThink principal Jim Venturi, the change is positively mundane.

“The pontoon bridge and the ferries and all these other things, they're more splashy—literally—and this is just a pretty boring, real proposal that has the secondary benefit of moving half the amount of people on the L train,” Venturi says. He’d had the idea for the looping E train several years before the L train shutdown was announced, but the crisis seemed like the perfect moment to bring it to a broader audience. Venturi also believes his idea has a life beyond the 15-month event. “It’s a proposal for the future of New York,” he says. “It just so happens that it would help the L train shutdown tremendously.”

Finally, on the most reasonable side of the spectrum is the advocacy group Transportation Alternatives’ “PeopleWay”, which would depriortize private vehicles on Manhattan’s busy 14th Street, focusing instead on free, 24/7 bus service and two-way, protected bike lanes. It’s perhaps the most modest of the myriad proposals, because it requires no ambitious construction.

Whether the agencies ultimately responsible for handling the shutdown will be receptive to the flood of suggestions is another matter entirely. The city's transportation department says it is reviewing public input about ideas like pontoon bridges and gondolas, and the MTA did not respond to a request for comment. The city is also mulling its own (more) pragmatic plans, which resemble a pared-down version of Transportation Alternatives’ proposal: creating a dedicated “busway” on 14th street during peak hours; building a new two-way, protected bike lane on 13th street; and prioritizing buses on the Williamsburg Bridge during rush hour. Each element has to go through a lengthy process of analysis and public vetting, and already, some neighborhood residents have filed a lawsuit in an attempt to get the city to conduct an environmental review of its current plans and install ADA-accessible elevators during the shutdown.

“I think everyone recognizes it’s an important moment for the future of New York City transportation and transit,” says Paul Steely White, Transportation Alternatives’ executive director. “It’s one of these classic junctures where we can prove some new innovations will work.”

The key will be bottling this newfound mass interest in transforming the city’s transit system, and extending it beyond this particular crisis, whose imminent arrival makes experimentation a risky game. But if the champions of those new solutions—the bartenders, the city planners, even the pontoon enthusiasts—can keep building on their big ideas beyond just the L train shutdown, they might manage to elevate New York City’s streets and subways, from laggards to leaders once again.

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