The $200 million project will add a fourth lane in both directions of the 26-mile tollway from Denton Tap Road in Lewisville to east of US 75 in McKinney.
Michael Rey, a spokesperson for the North Texas Tollway Authority, said the tollway was built to accommodate a future expansion project.
Construction work and planning in Plano will begin in the spring and will continue through the summer.
However, Plano engineering Director Caleb Thornhill said improving regional mobility will require more than widening roadways.
“There’s going to be multimodal things that the entire region is going to have to look at, whether that’s increased service from DART, or other type of rail opportunities,” Thornhill said. “I think we are all interested in seeing what that will be in the future.”
The SRT’s annual traffic counts are expected to increase by nearly 39 million transactions between 2015-22, according to NTTA projections.
“It’s our job to provide mobility to North Texas,” Rey said. “As the congestion builds … we have to make the decision to reinvest into the roadway to try to decrease that congestion—that’s all part of the region’s plan.”
The project’s anticipated completion in late 2021 will mark the end of construction along the tollway for the foreseeable future, Rey said.
Construction crews began working on the 26-mile Sam Rayburn Tollway project in January. They are adding the fourth lanes in either the median or on the outside edges of the tollway.
NTTA staff has since met with business groups along the tollway to keep them up to date on the status of the construction project.
Starting in the spring, crews began widening overpass bridges. Three Plano intersections at Sam Rayburn Tollway are affected by the construction. Those intersections are Legacy Drive, Rasor Boulevard/Hillcrest Road and Coit Road.
The construction will also affect the intersections at Parkwood Boulevard and Preston Road, but that construction will begin in the summer.
Thornhill said the city is not conducting any additional construction projects along the tollway.
“We don’t have anything that we are planning to construct solely for the purpose of the widening of [Sam Rayburn Tollway],” Thornhill said.
However, the city is coordinating with the NTTA to determine which ramps might be in need of updating, he said.
“One of the challenges that we have, especially with the growth that we have seen particularly in the northwest area, is traffic on the frontage roads,” Thornhill said. “We’re working with NTTA as far as ramp configurations … to see if there are any improvements that can be done to assist Plano travelers.”
Part of this summer’s construction will include the replacement of the eastbound Parkwood Boulevard and Preston Road exit ramps. Crews will also construct lanes to separate traffic exiting onto Preston Road from traffic merging onto the SRT from the Dallas North Tollway.
Rey said full lane closures may occur in Plano and Frisco. Any overnight or weekend lane closures will be determined on a weekly basis.
Part of the increase in regional congestion can be attributed to the thousands of employees commuting to new corporate headquarters along the tollway, such as Toyota Motor North America, JPMorgan Chase & Co., and Liberty Mutual.
“We’ve had this enormous concentration of development along our roadways, so I mean [the widening project] is an answer to some of these gigantic companies that are moving to the area,” Rey said.
The $200 million project will be funded through toll fees collected by the NTTA.
Kevin Feldt, the program manager for the North Central Texas Council of Governments, said the NTTA’s projects are a, “You bring your own money, you get your own project” kind of deal.
“We view the NTTA project as cost- and revenue-neutral in that they have the money to construct, operate and maintain their projects,” he said.
The added capacity will help alleviate traffic conditions as the North Texas population continues to grow.
The NCTCOG projects the region’s population will increase from 7.4 million today to about 11.2 million in 2045. The NCTCOG works with cities, counties and transportation agencies to better coordinate regional planning.
Meanwhile, the NTTA saw its annual transactions increase from 141.8 million in 2015 to 167.7 million in 2018. It projects those transactions to rise by another 13 million over the next three years, according to NTTA data.
A transaction is recorded any time a vehicle passes through a toll, which means one vehicle could have multiple transactions during a single trip.
Rey said although transactions are anticipated to increase along the tollway, there are no future plans to add a fifth lane.
Adding more than four lanes on a highway can have a degrading effect on traffic, Feldt said. More lanes result in vehicles changing lanes more frequently, which causes heavier congestion.
Transportation planners should explore more solutions to improving regional mobility other than expanding highways, Feldt said.
“It’s not just about the big roads that we have,” Feldt said. “We also need to think about our arterial network of roadways as well. And we need to think about public transportation projects.”
The city of Plano announced in April it has partnered with employers and property owners in the Legacy business area to form a transportation management association to help mitigate future congestion issues.