Texas State Highway Loop 1

From the AARoads Wiki: Read about the road before you go
Jump to navigation Jump to search

State Highway Loop 1

MoPac Expressway
Loop 1; mainline in red, toll routes and lanes in green
Route information
Length25.698 mi[1] (41.357 km)
Major junctions
South end SH 45
Major intersections
North end SH 45 Toll
CountryUnited States
CountiesTravis, Williamson
Highway system
SH 1 FM 1

Loop 1 is a freeway which provides access to the west side of Austin in the U.S. state of Texas. It is named Mopac Expressway (or, according to some highway signs, Mopac Boulevard) after the Missouri Pacific Railroad (or "MoPac"). Local residents almost always use the name "MoPac" rather than calling the road by its number,[2][3] which can cause much confusion, for few signs along the road use this name.[4][5]

The original section of the highway was built in the 1970s along the right-of-way of the Missouri Pacific Railroad (now owned by Union Pacific), with the railroad tracks running in the highway median between West 8th Street and Northland Drive. To the north, the tracks run along the east side of newer sections of the highway from Northland Drive to Braker Lane.


Route designation

The first mention of Loop 1 in public record was in 1929. In 1944, the City of Austin Planning Commission (CMAC) proposed that the highway be built in parts of the under-utilized right of way owned by the MoPac Railroad. Thus, the highway was eventually given the nickname "MoPac" for its proximity to the railroad. The current Loop 1 was designated on October 27, 1967, from US 290 northward to Farm to Market Road 1325 (FM 1325).[6] On October 24, 1985, the designation was extended southward from US 290 to SH 45.[1]

Expressway construction (1969 to 2006)

This table contains the dates of the construction of segments of the road.[7][8][9]

From To Length
RM 2244
(Bee Cave Road)
RM 2222
(Northland Road)
5.4 8.7 February 1969 November 1975 Loop 1 project started with
construction of the 45th Street
Interchange in February 1969.
RM 2222 US 183 4.6 7.4 September 1977 June 1981 Northern terminus of Loop 1 completed,
until July 1989 - with construction of the freeway extension to FM 734.
RM 2244 Loop 360 1.9 3.1 January 1979 March 1982 Southern terminus of Loop 1 completed,
until October 1989 - with construction of the freeway extension to US 290.
Loop 360 US 290 1.6 2.6 October 1983 October 1989 Southern terminus of Loop 1 completed,
until November 1990 - with construction of the roadway
extension to Slaughter Lane.
US 183 FM 1325 (Burnet Road)
and FM 734 (Parmer Lane)
3.7 6.0 January 1986 July 1989 Northern terminus of Loop 1 completed,
until October 2006 - with construction of the SH 45 North/
Loop 1 Connector toll road.
Stack interchange at US 183 is constructed -
involved major freeway improvements between Steck Avenue and US 183,
from March 1987 to June 1992.
US 290 Slaughter Lane 3.6 5.8 January 1988 November 1990 Southern terminus of Loop 1 completed,
until July 1991 - with construction of the roadway
extension to La Crosse Avenue.
Slaughter Lane La Crosse Avenue 1.0 1.6 July 1989 July 1991 Southern terminus of Loop 1 completed,
until May 1994 - with construction of the roadway
extension to State Highway 45 .
La Crosse Avenue SH 45 2.5 4.0 November 1989 May 1994 Southern terminus of Loop 1 completed.
FM 734 SH 45 North/
Loop 1 Interchange
4.0 6.4 February 2003 October 2006 Construction on the SH 45 North Interchange
began in September 2003.
Northern terminus of Loop 1 completed.

Route description

A stretch of Loop 1 over the Hancock Drive bridge, looking north-northwest. The Union Pacific railway is visible in the foreground.

Loop 1's southern terminus is at the beginning of the State Highway 45 stub south of Austin. It passes through the Circle C Ranch housing development and the Edwards Aquifer and intersects SH 71/US 290 (Ben White Boulevard) and Loop 360 (Capital of Texas Highway). It crosses the Colorado River near downtown Austin; the view of the Texas State Capitol from the bridge became one of the Capitol View Corridors protected under state and local law from obstruction by tall buildings in 1983.[10] North of the river, the highway runs parallel to the Balcones Fault and the Missouri-Pacific Railroad (Union Pacific) before it intersects US 183 (Research Boulevard) northwest of downtown. Loop 1 travels concurrently with Farm to Market Road 1325 for several miles before the non-tolled freeway ends at Parmer Lane, spanning a distance of 22.061 miles (35.504 km).

Loop 1 is designated a scenic roadway by the City of Austin.[11]

Major construction projects

Loop 1 Toll

North of Parmer Lane, Loop 1 continues as a limited-access toll road to the SH 45 North/Loop 1 interchange, spanning 3 miles (4.8 km). Frontage roads flank either side of the toll road to Merrilltown Drive.

The Texas Department of Transportation completed construction of the tollway as part of the 2002 Central Texas Turnpike Project (CTTP). SH 45 North, also part of the project, provides freeway access to Interstate 35 from Loop 1. The 2002 CTTP was scheduled to be completed in September 2007. However, certain sections of the project, including Loop 1 opened early and more than $100 million under budget.

If and when SH 45 is completed to the south of Austin between FM 1626 and I-35, Loop 1 will effectively serve as a full western loop to the city, being directly connected to SH 45 (and indirectly to I-35) at both ends.

MoPac Improvement Project

Loop 1 Express

Mopac Improvement Project

Since 1994, TxDOT has proposed the addition of managed lanes to portions of Loop 1. The MoPac Improvement Project[12] was relaunched in July 2010 by the Central Texas Regional Mobility Authority (CTRMA). In December 2010, four alternative proposals were presented to the public, each of which would add one or more lanes; the "no-build" alternative was also presented. The additions would not increase the right-of-way of the highway, but would be created by reducing the width of existing lanes and reducing and/or eliminating shoulders. An environmental study was completed in August 2012 with a Finding Of No Significant Impact and a recommendation of one new travel lane in each direction, operated as express lanes.[13] Construction began in 2013, and was originally scheduled for completion in September 2015, but by August 2016, the Central Texas Regional Mobility Authority announced further delays.[14] The first of four tolled sections, specifically the northbound toll lane from RM 2222 to Parmer Lane, opened on October 17, 2016. The remainder of the northbound express lane, from Cesar Chavez Street to Parmer Lane, opened on October 7, 2017, and the entire southbound express lane opened on October 28, 2017.

MoPac Intersections Project

In 2013, CTRMA and TxDOT initiated an environmental study to analyze the best options to improve the MoPac intersections at Slaughter Lane and La Crosse Avenue. In December 2015, the study was completed with a Finding Of No Significant Impact for the project, which allowed it to move forward.[15] The selected design included replacing the at-grade intersection at Slaughter Lane with a diverging diamond interchange (DDI)[16] and the at-grade intersection at La Crosse Avenue with a diamond interchange. The project broke ground in January 2018 with Webber, LLC as the general contractor.

On August 10, 2018, the at-grade Slaughter Lane intersection was rerouted to the south as construction began on an overpass bridge on the original alignment.[17] The completed DDI opened to traffic on November 11, 2018, with final completion occurring in Spring 2019. The La Crosse Avenue intersection began construction in Fall 2018. On March 29, 2019, the La Crosse Avenue at-grade intersection was closed for reconstruction as a bridge.[18] The La Crosse Avenue bridge and intersection opened to traffic on April 16, 2020. The full project, including surrounding sound walls and retention ponds, was officially completed on December 16, 2020.[19][20]

MoPac South

In 2013, CTRMA and TxDOT initiated an environmental study of the MoPac corridor from Cesar Chavez Street to Slaughter Lane.[21] The environmental study identified the Express Lane(s) Alternative as the Recommended Build Alternative.[22] In October 2015, six proposals were presented to the public, each of which would add one of more express lanes; the "no-build" alternative was also presented.[23] In February 2016, the project was put on hold by a Save Our Springs lawsuit claiming the project had not complied with the National Environmental Policy Act's requirements for environmental studies.[24] The lawsuit was settled on July 18, 2018 with a ruling in favor of CTRMA by the 5th Circuit U.S. Court of Appeals.[25] However, the project was further delayed by a state moratorium on toll projects receiving funding from State Propositions 1 and 7. TxDOT gave CTRMA preliminary approval to resume planning for MoPac South in August 2019.[26] In November 2021, the project was officially revitalized with a virtual open house, and it is currently in public planning phases with construction projected to start 2023.

Exit list

All exits are unnumbered.

SH 45 west
0.71.1South Bay LaneAt-grade intersection; dead end both directions, turnaround only
1.52.4La Crosse Avenue
2.33.7Slaughter LaneDiverging Diamond Interchange
2.94.7Davis LaneSouthbound exit and northbound entrance
4.77.6William Cannon Drive
6.09.7 US 290 / SH 71 / Southwest Parkway – Johnson City, Llano, Sunset ValleyAccess to Baylor Scott & White Medical Center – Austin
6.610.6Frontage RoadSouthbound exit only
7.512.1 Loop 360 (Capital of Texas Highway)Only one exit ramp travels from southbound Loop 1 to southbound Loop 360; all others are at-grade
8.914.3Barton Skyway
9.815.8 RM 2244 (Bee Caves Road) / Wallingwood Drive – Rollingwood, West Lake Hills
Roberta Crenshaw Bridge over the Colorado River
Loop 1 ExpressSouth end of variable toll lanes
10.516.9Cesar Chavez Street / 5th Street / Lake Austin Boulevard
11.218.0Enfield Road
11.718.8Windsor Road
12.319.8Westover Road / Northwood Road
12.920.8 35th Street - Camp MabryAccess to Seton Shoal Creek Hospital
13.822.245th Street
14.823.8 RM 2222 (Northland Drive)
Loop 1 ExpressAccess point for variable toll lanes
15.925.6Far West Boulevard
16.626.7Anderson Lane / Spicewood Springs RoadDirect northbound exit and southbound entrance (southbound exit signed at Steck Avenue)
17.127.5Steck AvenueNo direct northbound entrance
17.327.8(no name)Northbound exit only; replaced by northbound collector distributor road underneath Steck Avenue[27]
18.029.0 US 183 (Research Boulevard)No direct southbound exit to US 183 north (signed at Capital of Texas Highway), access to Seton Northwest Hospital
18.730.1Capital of Texas Highway
19.130.7Braker Lane - Q2 StadiumDirect southbound exit and northbound entrance (northbound exit signed at Capital of Texas Highway)
FM 1325 south (Burnet Road) / Duval Road
South end of FM 1325 overlap, access to North Austin Medical Center
Loop 1 ExpressNorth end of variable toll lanes; despite being signed as such, no direct access to FM 734 (Parmer Lane) exists
21.734.9 FM 734 (Parmer Lane)
22.436.0Scofield Ridge Parkwayno direct southbound exit
23.137.2 FM 1325 / Wells Branch Parkway / Howard Lane, Merrilltown Drive Howard station
24.038.6Toll plaza
county line
24.539.4Shoreline DriveNo southbound exit
SH 45 Toll to I-35
1.000 mi = 1.609 km; 1.000 km = 0.621 mi

See also


  1. ^ a b Transportation Planning and Programming Division (n.d.). "State Highway Loop No. 1". Highway Designation Files. Texas Department of Transportation. Retrieved March 24, 2013.
  2. ^ "Confusing Road Names in Austin". Archived from the original on October 25, 2011. Retrieved January 2, 2012.
  3. ^ "Austin Slang - AOL Travel News". Archived from the original on January 20, 2012. Retrieved January 2, 2012.
  4. ^ "Decipher Austin streets | Always Austin". Archived from the original on April 26, 2012. Retrieved January 2, 2012.
  5. ^ "MoPac Expressway. Just wondering | Austin | Yelp". Archived from the original on March 4, 2016. Retrieved January 2, 2012.
  6. ^ "Proposed MoPac Boulevard Is Designated as Loop No. 1". Austin Statesman. October 31, 1967. ProQuest 1515952796. {{cite news}}: |url-access= requires |url= (help)
  7. ^ "Introduction: Mopac Improvement Project, April 2012" (PDF). Retrieved April 1, 2012.
  8. ^ "The MoPac 1 Project will study feasibility of managed lanes for Loop 1, and included in the Mobility 2030 Plan that was adopted by CAMPO in June 2005". Archived from the original on February 23, 2006. Retrieved June 1, 2005.
  9. ^ "What Native American tribe was most common in the area?". Texas Department of Transportation. Archived from the original on May 7, 2010. Retrieved January 24, 2010.
  10. ^ "Downtown Development and Capitol View Corridors" (PDF). Downtown Austin Commission. June 27, 2007. Archived (PDF) from the original on November 15, 2017. Retrieved November 10, 2017.
  11. ^ "Code of Ordinances § 25-10-7". City of Austin. Retrieved October 28, 2022 – via Municode.
  12. ^ "MoPac Improvement Project". Archived from the original on December 30, 2010. Retrieved February 19, 2011.
  13. ^ Ham, Justin. "Finding" (PDF). MoPac Improvement Project. U.S. Dept. of Transportation, Federal Highway Administration, Texas Division. Archived (PDF) from the original on May 10, 2017. Retrieved September 5, 2016.
  14. ^ Jechow, Andy (August 25, 2016). "Weather, paving corrections push back North MoPac opening date". KXAN-TV. Archived from the original on August 29, 2016. Retrieved September 5, 2016.
  15. ^ "About MoPac Intersections". Archived from the original on February 19, 2018. Retrieved February 18, 2018.
  16. ^ "MoPac South: Diverging Diamond Interchange Simulation". Central Texas Regional Mobility Authority. April 16, 2015. Archived from the original on 2021-12-13. Retrieved September 30, 2018.
  17. ^ Crown, Rosemond (June 11, 2018). "Construction to close Slaughter lane at MoPac for 6 months". KXAN. Archived from the original on April 2, 2019. Retrieved April 2, 2019.
  18. ^ Cicale, Nicholas (March 29, 2019). "Detours for La Crosse Avenue at MoPac go into effect March 29". Community Impact Newspaper. Archived from the original on April 2, 2019. Retrieved April 2, 2019.
  19. ^ Cicale, Nicholas (2020-12-16). "MoPac projects at Slaughter Lane, La Crosse Ave. completed". impact. Retrieved 2021-11-05.
  20. ^ "MoPac Intersections". www.txdot.gov. Texas Department of Transportation. Archived from the original on September 27, 2018. Retrieved September 27, 2018. Note: This source incorrectly refers to interchanges as intersections.
  21. ^ "Project Overview | MoPac South Environmental Study". www.mopacsouth.com. Retrieved 2021-11-05.
  22. ^ "Environmental Study | MoPac South Environmental Study". www.mopacsouth.com. Retrieved 2021-11-05.
  23. ^ "Mobility authority unveils MoPac South options". Austin Monitor. 2015-10-22. Retrieved 2021-11-05.
  24. ^ "Group files lawsuit to stop South MoPac, SH 45 SW projects". KXAN Austin. 2016-02-25. Retrieved 2021-11-05.
  25. ^ Cicale, Nicholas (2018-07-19). "Court rules on the side of CTRMA and TxDOT in lawsuit against South Austin transportation projects". impact. Retrieved 2021-11-05.
  26. ^ Ortiz, Edmond (2019-11-07). "Austin: Mobility Authority Resumes Planning for New MoPac South Toll Roads". Virtual Builders Exchange. Retrieved 2021-11-05.
  27. ^ "Mopac Improvement: Steck Avenue Collector-Distributor Lane Construction". Archived from the original on June 9, 2016. Retrieved June 22, 2016.

External links