Greater Miami Expressway Agency
organization that toll expressways
The Greater Miami Expressway Agency (GMX) (formerly the Miami-Dade Expressway Authority, MDX) is an independent agency governed by the state of Florida. Since 1997, GMX has operated and maintained five expressways that run within the county.
All five expressways are all electronic toll roads, requiring the use of SunPass or a "toll-by-plate" program and does not accept cash, and the free movement sections were removed. The Gratigny Parkway, Don Shula and Snapper Creek Expressways became all electronic in 2010, while the Airport and Dolphin Expressways were converted in 2014.
History
Beginnings (1994–2018)
In December 1994, the state of Florida along with the Miami-Dade County commission created the Miami-Dade Expressway Authority. This gave the county full control of five toll-road expressways that were formerly under the control of the Florida Department of Transportation (FDOT). Those were the Gratigny Parkway (State Road 924, SR 924), Airport Expressway (SR 112), Dolphin Expressway (SR 836), Don Shula Expressway (SR 874), and the Snapper Creek Expressway (SR 878). Control took effect in 1997.
Since then, MDX has completed projects both independently and in collaboration with FDOT most notably the western expansion on the Dolphin Expressway in 2004 and the Dolphin–Palmetto Interchange in 2009.
Takeover by the state (2019-present)
Problems began to arise in 2014 when MDX doubled its toll-enforcement.
Begin with the source’s own compact description: “Greater Miami Expressway Agency” is organization that toll expressways. The dossier treats that line as a proposition to test through Greater, Miami and Expressway, not as a finished interpretation.
Why this record matters
The phrase “organization that toll expressways” supplies a clear boundary for inquiry. It also exposes the unanswered questions: who defined that boundary, when it became stable and which sources sit outside it.
The record creator and administrative purpose are central evidence, because official documentation reflects both action and institutional priorities. The source revision retrieved here is dated Aug 8, 2026. The linked authority identifier is Q6827241. 2 of 2 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 1997, 2010, 2014 and 1994.
Later summaries often reconcile disputed chronology or motive more neatly than the contemporary record permits. The source lead contains qualifying language; that uncertainty should survive quotation, summary and reuse. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
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This entry incorporates text from “Greater Miami Expressway Agency” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.