The other key part of BMW Designworks’ proposal is taking the L.A. River and other tributaries and filling them with enough water so these little submarines can travel around the city on these newly created “subways.” In the winter the water does flow tremendously deep through these channels, so they reasoned that flooding the channels permanently would create a dual benefit of replenishing L.A.’s groundwater and preventing billions of gallons of stormwater from flowing directly into the ocean.

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While we probably won’t have these fleets of Mini-subs taking over our waterways just yet, this concept does help us start to think of L.A. as more of a river city. The BMW Designworks team sees us not only using existing rivers and bays for transportation, but also reinstating Venice Beach’s canal system (which was once much larger than it is now), and possibly daylighting more creeks that have been asphalted over.

Maybe more feasible is a coastal transportation network—which, right now, only really consists of private ferries to Catalina—that would allow people in, say, Marina del Rey to commute to Long Beach via ferry instead of the 405 Freeway, or to take a water taxi from Santa Monica to Malibu and thus avoid traffic on the Pacific Coast Highway.