The Greater Miami Expressway Agency (GMX) (formerly the Miami-Dade Expressway Authority, MDX) is an independent agency governed by the state of

Florida Florida ( ; ) is a U.S. state, state in the Southeastern United States, Southeastern region of the United States. It borders the Gulf of Mexico to the west, Alabama to the northwest, Georgia (U.S. state), Georgia to the north, the Atlantic ...

. 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

along with the

Miami-Dade County Miami-Dade County () is a county located in the southeastern part of the U.S. state of Florida. The county had a population of 2,701,767 as of the 2020 census, making it the most populous county in Florida and the seventh-most-populous coun ...

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 The Florida Department of Transportation (FDOT) is a decentralized agency charged with the establishment, maintenance, and regulation of public transportation in the U.S. state of Florida. The department was formed in 1969. It absorbed the power ...

(FDOT). Those were the Gratigny Parkway (State Road 924, SR 924), Airport Expressway (SR 112), Dolphin Expressway (SR 836),

Don Shula Expressway Don, don or DON and variants may refer to: Places *Don (river), a river in European Russia *Don River (disambiguation), several other rivers with the name * Don, Benin, a town in Benin * Don, Dang, a village and hill station in Dang district, Gu ...

(SR 874), and the

Snapper Creek Expressway Snapper(s) may refer to: Animals * Lutjanidae, a family of fish known as snappers **''Lutjanus campechanus'', a fish found in the Gulf of Mexico and the Atlantic coast of the United States ** Bigeye snapper (''Lutjanus lutjanus''), a fish that ...

(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 The Dolphin–Palmetto Interchange, also known as 826–836, is a complex four-level stack interchange in Miami-Dade County, Florida. It primarily serves as a highway interchange between SR 826 (Palmetto Expressway) and SR 836 (Dolph ...

in 2009.

Takeover by the state (2019-present)

Problems began to arise in 2014 when MDX doubled its toll-enforcement. This caused backlash by many. In 2017, then State Representative Jeanette Nunez pushed a law ordering MDX to reduce its tolls. In 2019, the state took over MDX. In August 2023, a judge ruled that operations are to be taken over by GMX. Since then, MDX leaders have been fighting to regain control.

Markings

All GMX highways use the shield-shaped signs reserved by FDOT for toll roads, with the GMX logo attached below the shield. In addition, all GMX highways use a uniquely designed mileage marker. Instead of the green "MILE XX" markers commonly seen on

Interstate Highways The Dwight D. Eisenhower National System of Interstate and Defense Highways, commonly known as the Interstate Highway System, or the Eisenhower Interstate System, is a network of controlled-access highways that forms part of the National H ...

, the five GMX expressways use blue mileage markers featuring (from top to bottom, in white): a single letter indicating the direction of travel, the State Road designation of the highway (complete with outline of the State of Florida), and two numbers separated by a horizontal line ("2" on the top, "4" on the bottom of the line represents Mile Marker 2.4 from either the southern or western end of the expressway). These markers are placed on the edge of the

shoulder The human shoulder is made up of three bones: the clavicle (collarbone), the scapula (shoulder blade), and the humerus (upper arm bone) as well as associated muscles, ligaments and tendons. The articulations between the bones of the shoulder m ...

every along the expressway. The Gratigny Parkway has two of these (mile markers 5.0 and 5.2) on a surface street near

Opa-locka Opa-locka () is a city in Miami-Dade County, Florida, United States. Spanning roughly , it is part of the Miami metropolitan area of South Florida. As of the 2020 Census, the population was 16,463, up from 15,219 in 2010. Opa-locka was founded ...

on Northwest 119th Street just east of the end of its easternmost ramp). Prior to the removal of free movement sections, on portions of a GMX route where no tolls are ahead, the TOLL in the green section of the TOLL shield was removed.

Expressways

Airport Expressway

SR 112, locally known as Airport Expressway is a east–west expressway connecting Miami International Airport in Miami to Interstate 95 (I-95) and I-195, which ultimately connects to Miami Beach.

Dolphin Expressway

SR 836, locally known as the Dolphin Expressway, is a toll road currently extending from Southwest 137th Avenue in the west to I-95 in the east. The section of roadway east of I-95 is designated as I-395 or the

MacArthur Causeway The General Douglas MacArthur Causeway is a six-lane causeway that connects Greater Downtown Miami, Downtown Miami to South Beach via Biscayne Bay in Miami-Dade County, Florida, Miami-Dade County. The highway is the singular roadway connecting ...

Don Shula Expressway

SR 874, locally known as the Don Shula Expressway, is long, connecting the

Homestead Extension of Florida's Turnpike The Homestead Extension of Florida's Turnpike (HEFT), designated as unsigned State Road 821 (SR 821), is the southern extension of Florida's Turnpike, a controlled-access toll road in the U.S. state of Florida maintained by Florida's T ...

and Palmetto Expressway in central Miami-Dade County, Florida. As of July 17, 2010, the Don Shula Expressway no longer accepts cash.

Snapper Creek Expressway

SR 878, locally known as the Snapper Creek Expressway, stretches for between Don Shula Expressway (SR 874) and U.S. Highway 1 (US 1, South Dixie Highway). This provides access to Kendall and South Miami. Although constructed, improved and maintained through toll revenue, the Snapper Creek Expressway was untolled until July 17, 2010, when open road tolling (ORT) was initiated on the expressway.

Gratigny Parkway

SR 924, locally known as Gratigny Parkway, is a limited access all-electronic toll road running east to west. The Gratigny Parkway starts east of the Palmetto Expressway/I-75 interchange in Hialeah and ends at Northwest 32nd Avenue in North Miami. The section of roadway east of NW 32nd Avenue is a surface street (Northwest 119th Street) also known as Gratigny Road. Despite its relatively short length, SR 924 is a major east–west artery in northern Miami-Dade County, Florida.

References

External links

*{{official website, https://www.gmx-way.com/ Transportation in Miami-Dade County, Florida Toll road authorities of the United States 1994 establishments in Florida