Within a year after the new $5 million ThrU Turn was installed, the gas station indeed closed. But next to the abandoned store, severe traffic congestion has largely disappeared, and the traffic flows much more quickly at the intersection with Minuteman Drive.
These developments sharply illustrate the arguments for and against what is turning out to be a controversial intersection design. UDOT says ThrU Turns called Michigan U-turns in other areas of the nation are a great tool to speed traffic, but nearby businesses say it kills customer access. They have filled UDOT correspondence files with tales of struggle and worry.
"You could put up walls along the road with no access and you would have great flow-through. But that's not what it's all about. You need a balance of convenience to the consumer and also flow," Paul Hitzelberger, who owns a Del Taco on 12300 South, said in an interview. He owns 25 other Del Taco restaurants but says only the Draper store struggles lately because of the ThrU Turn.
Design • The unusual design of the ThrU Turn gives many businesses heartburn. It has been used at just two intersections so far, at 12300 South and Minuteman in Draper, and at 5400 South and 4015 West in Kearns.
It does not allow any left turns at the main intersection. Motorists wanting to turn left must go straight through the intersection and make a U-turn at a special intersection with a signal a few hundred feet down the road.
Drivers then must return to the main intersection and make a right turn to end up traveling in the desired direction.
Alternatively, drivers could also turn right at the main intersection, and then make a U-turn to return to the main intersection in the desired direction.
Robert Miles, UDOT traffic operations engineer, said ThrU Turns were selected in Draper and Kearns because they could relieve congestion while avoiding removing businesses at the crowded intersections for widening and could avoid even more expensive options such as building bridges.
He acknowledges they make drivers think differently.
"It looks significantly different. The order in which you make the movements for a left turn is different," he said. "To make a left, you make a right or you go through the intersection and make a U-turn and come back and make a right."
Complicating matters is that the design adds a physical median between the main intersection and the U-turn intersections preventing left turns across the road into businesses.
That means to get to some businesses, such as the closed Common Cents store, drivers must make two U-turns from some directions.
From the freeway to Common Cents, "You have to go through the intersection to do a U-turn to do a right turn to then do a U-turn to do another right turn," Hitzelberger of Del Taco said. "There's an expectation that people will do that. Well, they won't."
Traffic • A study for UDOT by Avenue Consultants says the ThrU Turn in Draper has helped to dramatically reduce congestion there. UDOT has yet to do such a study in Kearns because of some ongoing lane construction.
"The ThrU Turn reduces the average delay per vehicle at the intersection [in Draper] from 46 seconds to an average of 16 seconds," the study says. Consumer savings in time and gasoline are estimated at $1.25 million for the first year.
UDOT spokesman Adan Carrillo said the design change also helped solve a safety concern in the area.
"Cars were starting to stack up on I-15. That's never a good situation," Carrillo said. "You essentially have cars parked on the freeway" with other cars approaching them at high speed.
The biggest time savings are for cars that go straight through the intersection. Cars making combinations of U-turns and right turns to go left are generally spending more time up to 51 seconds longer than before in some directions, the study said.
"But cars are continually moving," Miles said. "Vehicles are more efficient if they are moving than just idling."
Miles said UDOT projected that if it did nothing at the intersection, congestion could have created seven-minute delays to get through it by 2030.
The study says that anecdotally, the ThrU Turn appears to have decreased accidents as a result of reducing left-hand turns but said more statistically reliable data over time is needed to verify that.
The study also found that about 20 percent of the relief at the intersection resulted from UDOT adding a new I-15 exit at 11400 South, and much of the traffic diverted shifted there.
"Traffic-wise, they are working very well. There are a lot of delays out there that have been saved," Miles said.
Business • The UDOT study says sales taxes collected by businesses in the area generally increased in the first six months after the ThrU Turn opened, so "there is no evidence that the ThrU Turn Interchange has reduced overall [shopping] trips or that it has negatively impacted overall economic activity."
Hitzelberger laughed when he heard that. "It's had a huge negative effect on the businesses," he said. "That's the reality."
Several businesses around ThrU Turns in Draper and Kearns declined interviews, but UDOT correspondence files show their concerns including the prophetic warning by Common Cents that it would be driven out of business in Draper.
Rancho Market in Kearns told UDOT it figured that reduced traffic from the ThrU Turn could put it out of business within a few years. Walgreens in Kearns, which reported it had the highest sales in the state for its chain, reported "extremely negative impacts." Wendy's restaurant officials in both Kearns and Draper worried the intersection would hurt business.
Hitzelberger of Del Taco wrote that the design was "destroying my business" in Draper. He expounded in an interview.
"Our guests are very frustrated with that intersection. ... Guests say, 'Wow, it's hard to get to your store,' " he said. "The signage is beyond terrible. It is so difficult and dangerous to figure out."
He had sharp criticism for UDOT.
"They've been incredibly successful in wrecking one of the best intersections in the whole state for business."
Miles said while UDOT likes the new intersections, it is still learning and open to discussions.
"We're still looking and listening and talking to people about it. We're learning," Miles said. "They [the intersections] are doing everything they were designed to do. Now it is a matter of educating, learning and communicating better how to make them work."