You Asked: Will ITD make changes to busy Idaho 55 intersection at Banks?

Image it: You’ve simply spent a calming, however tiring weekend climbing in Backyard Valley and all you’ll be able to take into consideration is hitting the hay at dwelling within the Treasure Valley. 

However, as you come down Banks-Lowman Street you gradual to a cease behind a sea of brake lights. Nothing strikes for minutes at a time, till you’ll be able to crawl forward a automotive’s size towards the intersection with Freeway 55. 

That is the scene on the busy intersection many Sunday afternoons in the summertime months as vacationers return to the Treasure Valley from getaways in McCall and Cascadee. The seemingly limitless stream of southbound site visitors creates lengthy backups on Banks-Lowman Street as vacationers are pressured to attend for few and much between openings between vehicles to show onto the freeway and head south. 

The Idaho Transportation Division has a research underway of the intersection to judge its choices to handle the backups, which ought to be accomplished later this yr. The research will study “viable choices” to handle the seasonable backups within the space and suggest early designs for learn how to enhance the world. 

“It’s a significant step in outlining the price of a mission and its prioritization in our long-range plan,” ITD spokesperson Jillian Garrigues wrote in an e-mail to BoiseDev. 

Flaggers work the intersection on vacation weekends to handle site visitors issues at the price of $3,500 per day. In 2022 there have been flaggers on the intersection for six days at a value of $28,000. 

However, the research, which was paid for with a grant from the Federal Freeway Administration, doesn’t imply the mission will get achieved. ITD would nonetheless want extra funds to complete the ultimate design, purchase the land to construct the mission, and full the development. 

An uncommon intersection poses challenges

ITD says there are numerous complicating components that make the summer time backup troublesome. 

One of many large obstacles to engaged on the intersection is the one-lane bridge on the west aspect of the intersection that results in a ship ramp on the river. Due to the one lane of journey on the bridge, it means vehicles turning out and in of the bridge want additional time to maneuver out and in, slowing site visitors. 

A 2018 weblog submit authored by former ITD spokesperson Jake Melder stated a stoplight would additionally gradual site visitors down, however otherwise than the present scenario. When requested concerning the intersection, Garrigues pointed BoiseDev to Melder’s weblog submit as a solution to our inquiries. 

“One other concern is {that a} sign will pressure the presently free-flowing site visitors on ID-55 to cease,” Melder stated. “This creates a queue. As that queue backs up, main security issues come up. Think about a driver coming down the mountain going 55mph, turning a nook and instantly coming upon break lights. A sign provides new security and mobility issues, with each bit as a lot danger of great damage as the present situation, and presumably extra total delay for vacationers.”

A roundabout would additionally assist ease the congestion on the intersection on vacation weekends, however they require a big space to function in. This intersection is presently bounded by rivers and steep mountainsides, which ITD says leaves it little room to assemble a roundabout. Roundabouts additionally require two lanes of journey out and in to permit for correct and protected passing, however the one-lane bridge complicates this as a result of it wouldn’t have a manner for 2 lanes of site visitors to show proper onto the bridge. Boise County, not ITD, owns the bridge.

“Issues are very tight with three of the quadrants bordered by rivers and the final hugging a mountainside,” Melder wrote in his weblog submit. “A roundabout would both require an enormous bridge construction or important carving out of the mountainside.”

What a few new bridge?

The third possibility below research would add a 3rd lane for southbound site visitors open for left-turning site visitors from Banks-Lowman. Then, as soon as somebody turns onto the freeway they may use that third lane to realize pace and merge onto Freeway 55. 

This could require the development of a brand new, wider bridge on the southern finish of the intersection to make room for the third lane. As a way to match a wider bridge into the world, ITD must minimize into the mountainside each north and south of Banks-Lowman so as to add area for the lane. 

“The silver lining for this feature is the age of the bridge on ID-55,” Melder wrote. “Although it’s protected at this time, it must get replaced within the close to future attributable to its age and situation. Changing it with a wider bridge turns into far more cost-effective at the moment. At present, this bridge will not be scheduled for alternative in our 7-year plans.”

‘Bang for the taxpayers’ buck’

ITD says the mixture of comparatively low site visitors counts on the hall and low charges of lethal crashes on the intersection makes it exhausting to get “probably the most bang for the taxpayers” buck. 

In July, common weekday site visitors on the intersection was roughly 10,400 autos, and the numbers climbed to 13,201 on weekends, break up equally going north and south. That is up from 6,500 vehicles touring this stretch on a typical summer time weekday in 2018, as Melder reported in his weblog submit. 

By comparability, 28,273 autos traveled previous the outdated HP Campus on Freeway 20 in July on the common weekday and 19,284 on weekends. On Freeway 16 south of Freeway 44, 22,149 autos moved by way of the world on a median weekday in July. One other 16,318 drove the stretch on the common weekend in July. 

Melder’s weblog submit additionally reported solely 5 crashes on the Banks-Lowman and Idaho 55 from 2013-2017, the most recent information on the time of his weblog submit. Of these, two resulted in solely harm to autos, two ended with minor accidents, the ultimate crash had one “severe damage” and two individuals walked away with minor accidents. There was additionally a sixth lethal crash in 2018 the place one particular person died. 

ITD says on the time in 2018 the Banks-Lowman intersection didn’t price within the prime 1,000 intersections statewide for frequency and severity of crashes. 

“As we contemplate all of those actions, we now have to weigh the price/profit,” Melder wrote in 2018. “The long-range choices explored above will value tens of hundreds of thousands of {dollars}. And within the context of crash information and congestion, it’s removed from our highest precedence. That doesn’t remove the potential of making enhancements, it simply makes it a lot more durable.”