Some drivers say more traffic on a stretch of US 380 in northern Collin County also means more unsafe driving.
Drivers say it is normal to see speeding, tailgating and other reckless driving behaviors between McKinney and Denton.
"I have semis going by me at 70, 80 mph, and that can get a little scary," said Matt Cox, of Frisco.
"I've lived in Galveston County, Harris County, Tarrant County, Dallas and Collin, and this is by far the most aggressive driving that I've seen," said Kevin Shelby, who drives east from Aubrey on a daily basis.
However, Frisco police, the agency that normally responds to crashes and calls on US 380, said the area has not seen a major uptick in crashes this year. Many reported crashes stem from right-of-way violations such as running red lights and stop signs, police said.
Drivers said other agencies, such as Prosper police and the state troopers, are stepping up enforcement.
"I haven't seen any major accidents, but there have been lots of fender benders -- at least once per week," Shelby said.
Cox, whose office faces the highway, said enforcement has made some limited progress.
"It's helped some, but people still drive fast," he said.
He said he hopes the completion of road improvement and infrastructure projects, such as an overpass into Prosper, will eventually ease congestion.
But others said the traffic is a good thing. At 380 Family Dentistry, which faces the highway, Dr. Travis Campbell said he scouted the location to drive in patients to his practice.
"The highway was the biggest part," he said. "[US] 380 is one of the biggest highways around here, so we knew the traffic was going to be pretty good."
Campbell said recent measures, such has the addition of a traffic light near his office, also helped properly direct traffic.