Miami-Dade County may be unable to expand its transit network without raising taxes, according to an internal memo co-authored by Mayor Daniella Levine Cava and the Department of Transportation and Public Works.

The document, first obtained by the Miami Herald, lays out the funding challenge facing the five remaining corridors of the county's Strategic Miami Area Rapid Transit (SMART) Program: the North, Beach, East-West, Kendall, and Northeast corridors. Not one of the five has secured construction funding. The memo frames new taxes as a likely prerequisite — not a last resort — for getting any of them built.

The warning arrives at a moment when transit advocates and elected officials have spent years promoting the SMART Program as a generational fix for one of the country's most car-dependent metro areas. Miami-Dade's road network routinely ranks among the most congested in the nation, and commuters in communities stretching from Kendall to the Northeast corridor have been promised faster, more reliable connections for well over a decade.

So far, only one SMART corridor has made it to launch: the South Dade TransitWay, which serves communities in the county's southern reaches. The remaining five corridors have advanced through planning and environmental review stages at varying speeds, but none have crossed into funded construction — and the memo suggests that gap will not close on its own.

The document outlines potential funding strategies but stops short of endorsing a specific tax mechanism or dollar figure. Any tax increase affecting Miami-Dade residents would require voter approval, meaning the path forward involves not just political will at the county level but a countywide ballot campaign.

The stakes are considerable. Each corridor represents a distinct community with its own commuting pressures. The Beach Corridor would connect Miami Beach to the mainland; the Kendall Corridor would serve one of the county's densest suburban zones; the East-West Corridor would link major employment centers; and the North and Northeast corridors would extend rapid transit deeper into underserved communities that have long relied on an aging bus network.

The memo does not set a deadline or propose a specific ballot date, leaving the timeline open. But its existence signals that the administration is moving from aspirational planning language toward a harder fiscal conversation with the public.

Original reporting on this story was published by WLRN.