The projects belong to the Idaho Transportation Department, but stakeholders will have a lot to say about how the busy road looks when the work is done.
The list of people with a vested interest in the overhauls of the Broadway Bridge and the avenue’s Interstate 84 overpass includes the city of Boise, St. Luke’s Boise Medical Center, Boise State University and business managers on both sides of the bridge.
St. Luke’s is in favor of “whatever would increase the traffic flow to our facility,” spokesman Ken Dey said.
Joel King, general manager of the Chili’s on Broadway just south of the Boise River, is worried that crews will shut down the existing bridge for 10 months while building a new one. That would cripple his business, he said, particularly the lunch rush.
“Half my crowd comes from Downtown,” King said.
The university wants the new bridge to accommodate more pedestrian and bicycle traffic — which makes sense when you consider the thousands of Broncos fans who walk across the bridge to and from football games, the new Dona Larsen sports park and events on campus.
The city is largely on the same page as Boise State. Like the university, Boise wants to promote bike and foot traffic, comprehensive planning manager Patricia Nilsson said. But Boise also wants the bridge to accommodate more vehicles, Nilsson said, because it has become a bottleneck.
LOOKING AT ALTERNATIVES
About 25,000 vehicles cross the 55-year-old Broadway Bridge each day, and it wasn’t designed for that much traffic, said Reed Hollinshead, an ITD spokesman. That, more than its minor structural defects, is driving the bridge’s replacement, he said.
Whatever shape the new bridge takes needs to fit a larger upgrade of Broadway as a major corridor to and within the city, Nilsson said. Bike lanes — on a road heavily traveled by students — is a priority addition, she said.
Hollinshead said the bridge project could include additional work on Broadway. One option is to widen the road between Myrtle Street and University Avenue. Another is to repave it between University and Front Street.
Every alternative includes replacing the bridge, Hollinshead said.
The project is in its infancy, so it’s difficult to say what improvements will be included or what the final cost will be, Hollinshead said.
“If you want your project to be the bare minimum, where you have the bridge and nothing else, your costs are going to be a lot lower,” he said.
To some degree, the extent of the project will depend on input from stakeholders, who began meeting with the state early this month.
Work on the bridge is slated to start in late 2014, shortly after work begins on the Broadway overpass.
Duration of the bridge project depends on how ITD chooses to handle it.
If the old bridge is shut down during construction, Hollinshead said, its replacement should be done in about 10 months. Keeping the bridge open would extend the construction period to about 18 months.
Hollinshead acknowledged that closing the Broadway Bridge for 10 months would be extremely disruptive for businesses, organizations and residents on both sides of the river.
RETHINKING THE FREEWAY OVERPASS
Like the Broadway Bridge, the I-84 overpass is near the top of ITD’s priority list, Hollinshead said. They share other similarities: Both are traveled by more cars than they were designed to accommodate, and their ultimate shape has yet to be determined.
Hollinshead said that one possibility is to install the same traffic-control system that’s in place on the Vista Avenue and 10 Mile Road interchanges. The placement of one large traffic light in the middle of the overpass — instead of multiple lights — is known as a SPUI, a single-point urban interchange.
At first, some drivers struggled to negotiate the revamped Vista and 10 Mile interchanges, Hollinshead said. But most of that uncertainty appears to have cleared up now.
“It’s kind of a learning curve, I guess,” he said. “Anytime you have something new, you have people who were used to (the old arrangement) for the last 40 years.”
The Broadway project is one of three Treasure Valley I-84 interchanges the state is looking to redo in the next few years. The others are at Meridian Road and Gowen Road.
These projects are much more expensive than the bridge. Final costs aren’t set and will depend on complexity of the project, amount of land the state has to purchase and anticipated traffic levels. About 70,000 vehicles travel on or under the Broadway interchange on an average day.
Rough estimates put the price tag on a new Broadway interchange at $44 million. The new Meridian interchange will cost around $40 million and the Gowen project about $28 million, Hollinshead said.
Money for the projects will come from federal allocations and bonds that allow the state to borrow money and repay it with future federal allocations.
Sven Berg: 377-6275
