Roundabout way to two lanes would cost $500K extra

BOISE, Idaho (KBOI) - A proposed roundabout to replace a congested five-way intersection in the North End may only provide temporary relief.

Current plans call for a single-lane roundabout that could be expanded in the future. The Ada County Highway District says it might have to do that within the next decade, an option that's more expensive than building multiple lanes at the same time.

"It's got different lanes coming in from every direction, so it's very, very busy," said Renee Chariton about the junction of 36th Street, Hill Road and Catalpa Drive.

An ACHD memo dated Jan. 29, 2012 notes if a single-lane roundabout is built, traffic is projected to exceed capacity within 5 to 10 years. "A single-lane roundabout would likely not be a noticeable congestion improvement over the performance of the current intersection," the document reads.

The design is called a "dog bone" roundabout. Making it expandable and then converting it in the future will cost an extra $500,000. ACHD spokeswoman Nicole Pineda said this is the best use of taxpayer dollars.

"The expandable-lane roundabout will give people the opportunity to get used to this unique shape," Pineda said. "It's right in front of a school, so we want to make sure people are really comfortable with that before we add another lane of traffic."

Boise City Council Member Elaine Clegg says based on traffic projections, a multi-lane roundabout won't be needed anytime soon -- and that extra lane would be dangerous.

"Rebuilding it as a two-lane roundabout as it was designed would not be safe for the pedestrians and bicyclists that need to get to the junior high school and activity center," Clegg told KBOI 2News.

ACHD's recommendation in 2012 was to put in both lanes upfront.

"If they are projecting that it's going to have to be changed in 5 to 10 years, then they need to just do it now and get it done and over with, and we'll all follow and adjust," said Gabrielle Hayes, who takes her dog to the park at Hillside Junior High School, which borders the intersection.

The highway district says the roundabout may need that second lane as soon as 2018, but traffic might move through there just fine for 10 or 15 more years... or even not longer. If the roundabout does need to be expanded, we'll have taken a roundabout way to get there at a price tag of $500,000.

An open house is scheduled for Thursday starting at 5:30 p.m. at the ACHD office in Garden City.