The $5 million construction project to reconfigure the intersection at Oracle and Ina roads and alter left turns has been postponed from this summer, as originally planned, until next year.
Bob Roggenthen, Pima County project manager, said they have run into problems purchasing nearby property, and are still negotiating some aspects of the design with the Arizona Department of Transportation.
Because parts of Oracle Road are under Pima County and ADOT jurisdiction, Roggenthen said both agencies have to come to an agreement on all aspects of the plan.
“Getting everything done is just taking a lot longer than we planned,” said Roggenthen. “There is a dual jurisdiction with ADOT, and the deal needs a little more scrutiny.”
Increased traffic counts at the intersection has forced county officials to label the project as a high priority. Currently, 96,000 cars pass through the intersection daily.
The traffic counts have increased by 58 percent over the last decade. In 1999, ADOT estimated 56,000 cars passed through the intersection daily.
Daily traffic counts are expected to increase up to 126,000 cars in the next 20 to 30 years.
Roggenthen said the increased traffic has created lengthy delays for motorists. It can take up to five light cycles for a motorist to get through the intersection, especially during the morning and afternoon rush hours, he said.
According to a project fact sheet produced by Pima County, “The current capacity of the Oracle Road/Ina Road intersection is woefully inadequate, creating a bottleneck in the regional transportation system and causing lengthy delays and backups, undesirable cut-through traffic in nearby neighborhoods, limited access to businesses in the area, and reduced air quality.”
To address the issues, the county will begin a $5 million project in January to redesign the intersection that will alter left turns on Ina Road.
Known as a “Michigan left,” Roggenthen said it may change how people make left turns at the intersection, but it will increase safety and speed up how quickly cars move through.
A “Michigan left” is an at-grade intersection design which replaces each left turn with a permutation of a U-turn and right turn. The design was given its name due to its frequent use along Michigan roads and highways since the late 1960s.
While planning the project over the last two years, Roggenthen said the biggest complaint from residents and motorists is that it could take even longer to get somewhere when needing to turn left.
Instead of allowing a left turn at the intersection, the new configuration will force motorists to turn right, and eventually make a U-turn.
However, Roggenthen said because it will take less time to get through the light, it ultimately will take less time in the end make the U-turn.
A 2011 study conducted by the University of North Carolina backs up Roggenthen’s statement.
According to the study, a Michigan left results in a “20-percent overall reduction in travel time compared to similar intersections that use conventional traffic designs.” The same study also cited a dramatic reduction in carbon emissions.
The Regional Transportation Authority will fund project.