State Highway 121, locally known as 121, is a diagonal state highway, angling from southwest to northeast through north central Texas. It runs from downtown Fort Worth, Texas at the junction of Interstate 35W to Bonham, Texas, just north of a junction with U.S. Highway 82.
Sections between downtown Fort Worth and Grapevine, Texas are freeway, including a small segment near Hurst, Texas that coincides with Interstate 820. At Bedford, Texas it has an interchange with State Highway 183, the Irving freeway that leads toward Dallas; it has an interchange with State Highway 360, which leads toward Arlington, Texas, just to the west of the north entrance to the Dallas/Fort Worth International Airport, to which State Highway 121 gives access. At Grapevine it has interchanges with State Highway 114 and Interstate 635 before the end of the freeway, where it becomes a surface road up to a split at Business 121 (which, as of 2008, is undergoing construction to convert to freeway standard) and a limited-access tollway that passes between Lewisville and Frisco.
It is very heavily traveled south and west of McKinney and has become an urban highway due to the rapid growth of the Dallas-Fort Worth Metroplex. Sections not yet of freeway quality are scheduled for upgrade or replacement as freeway; between Frisco and McKinney service roads are in place along with one overpass at Custer Road. Discussions have been held as to whether the upgraded freeway should be a toll road instead (see below), which has sparked controversy among area residents. North of McKinney the road is mainly a two-lane highway with some interchanges and is far less traveled than its southern segment.
It meets Interstate 35E at Lewisville, Texas, State Highway 289 near Frisco, Texas, U.S. Highway 75 and U.S. Highway 380 in McKinney, Texas, U.S. Highway 69 at Trenton, Texas, and State Highway 78 just north of Bonham.
Currently, TxDOT has not allocated funding for the SH 121 main lanes between Preston Road (State Highway 289) and US 75, although construction of the Hillcrest Rd overpass has begun as of January 2007 and the Preston overpass is now open to traffic. Preliminary schematics for a toll financed facility were completed in 2001, but project funding options and right-of-way acquisition at the proposed toll plaza areas are still not determined. The project is estimated at costing $214 million. Frontage road construction began in 2003 and was completed in 2006. A date for completion of main lane construction has not yet been determined (only a small portion around Custer Road, which was built along with the frontage roads, is currently in place).
Plans are to use only electronic toll collection with no tollbooths or toll collectors along both the route like Westpark Tollway in Houston. People will be able to use a transponder unit known as a TollTag attached to a vehicle's windshield, which communicates with overhead sensors to deduct tolls from the user's toll account. If a person does not have a TollTag, they can still drive on the tollway, because the overhead sensors will scan and record the licence plate number, locate the owner's address, and send a monthly bill showing their toll cost plus 1/3 of a toll cost (to cover the license plate processing) plus a $1.00 invoice fee.
The original portion of the toll road from Business 121 near Coppell to FM 2281 opened in May 2006, and toll collection started December 1 of that year. The tolled portion extended to Hillcrest Rd. in Plano on August 31, 2008.
To answer some of these complaints, Texas legislators pressed the Texas Department of Transportation to allow the NTTA to bid. The Authority announced their proposed bid in early May 2007, which would provide approximately $3.3 billion in road funding, but is based on traffic counts that differ from those used by Cintra.
|Tarrant||Fort Worth||Continuation beyond I-35W|
|Northbound exit and southbound entrance|
|Maxine Street||Northbound exit and southbound entrance|
|Richland Hills||Handley-Ederville Road|
|South end of I-820 overlap|
|South end of SH 183 overlap; signed as exit 24 southbound|
|Pipeline Road, Glenview Drive||Signed as exit 23 eastbound|
|North Richland Hills|
|, Tarrant County College Northeast Campus||Signed as exit 22A northbound|
|North end of I-820 overlap|
|Bedford-Euless Road||Signed as exit 22A northbound|
|Norwood Drive, Brown Trail|
|Bedford||Bedford Road, Forest Ridge Drive, Brown Trail|
|Central Drive, Forest Ridge Drive|
|South Entry, Irving||No southbound exit; north end of SH 183 overlap|
|Murphy Drive, Euless Westpark Way||Northbound exit is via SH 183 east|
|Stone Myers Parkway||Northbound exit and southbound entrance|
|Southbound exit and northbound entrance|
|William D. Tate Avenue||Southbound exit is via SH 114 west|
|South end of SH 114 overlap; northbound exit is via Tate Avenue|
|North end of SH 114 overlap|
|Bass Pro Drive|
|Southbound exit and northbound entrance|
|No northbound entrance|
|Gap in freeway (construction is underway to convert the gap to freeway standards, with interchanges planned at Freeport Parkway in Coppell and Sandy Lake Road in Grapevine)|
|Denton Tap Road|
|Lewisville||Northbound exit to I-35E north is via MacArthur Boulevard exit|
|Marchant Boulevard, Huffines Boulevard|
|(Main St.)||to Little Elm|
|Plano Pkwy./Paige Rd.|
|Plano||Spring Creek Pkwy.|
|Hillcrest Rd./Robinson Rd.||end freeway|