Motorists who use the southbound ramp to merge from N.C. 150 onto Interstate 77 at Exit 36 have only a relatively short distance to match speeds with 65 mph traffic.
But they'll have to wait until next summer for relief.
By July 2013, a third lane will be completed to the new Brawley School Road exit, eliminating the need for motorists to do a quick merge as they enter the highway.
The Exit 36 on-ramp is only about half the length of the acceleration lanes recently added elsewhere along the interstate, such as at the new Exit 31, as it slices through Iredell and Mecklenburg counties.
Officials at the N.C. Department of Transportation said it all goes back to when the Exit 36 interchange was built.
"Many of the interstates were constructed in the 1950s-1960s when the traffic volumes, design standards, development patterns and traffic patterns were vastly different than today," said Gregory Brew, DOT's roadway design engineer for the Charlotte area.
"While some of these existing entrance ramps are short by today's standards, they likely met the design standards at the time they were constructed."
Though he was unable to provide an exact construction date, Brew said the Exit 36 ramp was probably built in the "late '60s-early '70s time frame." None of that sits well with drivers who are forced to make a quick merge into traffic, lest they wind up overrunning the entrance.
"It is very hard to see the southbound traffic, and you have little room to merge onto the highway," said Kris Milstead, who lives in the Wyndham Shores section of Mooresville. She said she usually tries to avoid the Exit 36 ramp. "I am surprised there are not more accidents."
Maj. Bryan Anderson of Mooresville police said there has not been an unusual number of accidents or incidents attributable to the short ramp. Local motorists believe it's just a matter of time.
"You get behind a driver who's not familiar with the area, and they'll slam on the brakes," said Kim Williams of Mooresville. "That ramp is so short."
DOT officials said there are specific guidelines for the ramps being built on the Interstates today.
"If there are no constraints, the acceleration ramp length would normally be approximately 820 feet long, based on a 70 mph design speed of the Interstate," Brew said. "However, if the Interstate is on an upgrade or downgrade, this would affect the speed of the vehicles and the acceleration length would potentially need to be adjusted."
At Exit 36, temporary barrier walls are being used to control traffic during construction of the Brawley School exit. But those walls restrict any chance of extending the acceleration lane.
When the construction is completed, however, motorists will see the same type of traffic pattern as they do now when entering I-77 southbound from Williamson Road/Exit 33: three lanes from N.C. 150 to the new exit onto Brawley School Road. That should give them plenty of time to merge from the acceleration lane into the travel lanes of the Interstate.
For the next year or so, however, the Exit 36 squeeze play is still on, with a short acceleration ramp into 65 mph traffic.