There’s a stretch of U.S. 71 in south Kansas City where you’ll soon be able to drive 65 mph — legally.
The Missouri Department of Transportation will raise the speed limit from 55 mph to 65 mph on U.S. 71 from about a half mile south of 75th Street to just north of the 3-Trails Crossing interchange.
North of 75th Street the highway, also called Bruce Watkins Parkway, looks and functions like an urban road, with stoplights and numerous bridges.
South of 75th, it begins to appear like a freeway similar to Interstates 435, 49 and 470. Along that stretch, most drivers are not obeying the 55 mph speed limit.
There is no timetable set on when the speed limit will increase. The state department is waiting for the new speed limit signs to be made and then installed, which could happen later this month.
“It’s about a three-mile section,” said Derek Olson, district traffic engineer for MoDOT’s Kansas City district. “It’s got the same safety features as far as median guard cable and shoulders. So we are going to post it the same speed as the other roads in the area.”
The department, however, is not changing the speed limit along U.S. 71 in the area of the traffic signals. There are three traffic signals along the roadway between 75th Street to 55th Street. It would not be appropriate to have the higher speeds there.
“There can be a lot of confusion from the public about speed limits and about how we decide to set them,” Olson said.
Basically, research shows that the closer the speed limit is to the speed that the majority of drivers are driving, the lower the crash risk.
“If you have uniform speeds in the traffic flow, people aren’t driving as aggressively,” Olson said. “Because when you have someone quite fast and someone driving a lot slower, that creates tension in the traffic stream.”
Most people do drive a speed that is reasonable based on traffic conditions, Olson said.
Traffic engineers found that 85 percent of the people on the south more freeway-like section of U.S. 71 were driving closer to 70 mph, which is not surprising, Olson said.
“We want people to respect our traffic signs and laws, and appropriate speed limits do breed respect, not contempt,” he said. “Law enforcement can then focus on the few people who are driving grossly unsafe and at risk to the traveling public instead of everybody being basically breaking the law.”
Several intersections along Watkins Drive have been identified as having the highest number of vehicle wrecks in Kansas City, Deputy Chief David Zimmerman told police commissioners earlier this month.
When studying to see if the speed limits could be raised, transportation officials looked at crashes in the area, how wide the shoulders are, other safety features and the spacing of interchanges.
They found that the south section of the highway could handle a higher speed limit.
About 80,000 vehicles pass through that section of U.S. 71. That’s compared to about 85,000 vehicles that head north I-435 from the 3-Trails Crossing.
The transportation department has increased the speed limits in other parts of the city. In 2006, state transportation officials increased the speed limit on a 13-mile stretch of Missouri 152 in the Interstate 435 loop from 60 mph to 65 mph.
“It kind of helped. It is kind of bizarre,” deputy chief Zimmerman said. “It seems like, to me, you would want people to slow down and not speed up.”