For the week of September 18 - 24, 2002

Transportation study predicts crowded streets

Expect 40 percent to 80 percent increase by 2025

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"The forecast traffic growth cannot be accommodated on the existing configuration of Main Street."

MICHAEL BIRDSALL, Earth Tech senior transportation planner

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By GREG STAHL
Express Staff Writer

Ketchum’s streets are getting crowded, and they’re only going to become more congested unless public officials act to mitigate anticipated traffic growth.

A transportation planner Monday told the Ketchum City Council to expect 40 percent to 80 percent overall traffic growth by the year 2025. Those figures anticipate a 1.3 percent to 2.1 percent annual boost in Ketchum’s population and a 1.5 percent to 2.8 percent rate of annual employment growth.

By 2025, between 5,300 and 7,200 employees will work in Ketchum, compared to the 3,600 people who worked here in 2000, said Earth Tech Senior Transportation Planner Michael Birdsall.

"The forecast traffic growth cannot be accommodated on the existing configuration of Main Street," Birdsall wrote in a preliminary report, which was contracted by the city. "Either congestion will get much worse on several existing streets, or economic growth will stagnate, or both."

Ketchum hired Earth Tech last spring to draft a city transportation plan that could ultimately be added as part of the city’s comprehensive plan. The study cost $65,000, but $50,000 was supplied by a federal grant.

Monday afternoon’s meeting was a mid-study update during which Birdsall sought feedback on Earth Tech’s progress. A final version, which is anticipated to be much more comprehensive, will not be complete for another six months.

Nonetheless, Birdsall concluded already that "some sort of capacity increase is needed, just to keep things even."

He proposed three mitigation avenues for the city’s consideration:

• Increase the capacity of existing Main Street, by removing parking on one or both sides and adding through lanes and/or turn lanes.
  
  

• Develop a bypass route parallel to Main Street to handle the additional growth.
  
  

• Implement high-quality transit services and effective travel demand management programs to significantly reduce existing and future automobile travel demand.

A combination of the proposed solutions will probably be needed to keep traffic growth in check, the consultant said.

Improving Main Street’s capacity is the easiest traffic improvement to implement in the short run, Birdsall said, but "it will not provide enough capacity for long-range growth."

Creating a new bypass route on Second or Third avenues would provide "substantial new capacity for the long term," but would require years to plan, design and build, Birdsall said. Additionally, it might be the most politically challenging option, because traffic would be routed through residential areas and adjacent to the Ernest Hemingway Elementary School in West Ketchum.

Emphasis on countywide and local transit services, potentially including a paid parking program in Ketchum, "might reduce future travel by 10 percent to 30 percent," Birdsall said.

"Success is not certain," he added. "It requires a strong commitment over many years by city leaders, plus responsive cooperation by the traveling public.

"This strategy might be able to hold the line on traffic increases for the short-to-medium range future, but significant congestion relief would not occur. Eventually the forecast growth will surpass what this strategy can offer."

Birdsall explained that the majority of Ketchum’s traffic congestion is created by employees driving to and from work. In-flowing traffic enters en masse via Highway 75 and splits to various destinations, including Sun Valley, West Ketchum, Warm Springs and the industrial area. A diagram of the out-flowing traffic patterns looked a lot like a river basin map, with small streams feeding Main Street and Highway 75. In-flowing traffic is a river system flowing in reverse.

After digesting the report, city leaders pinpointed several areas they said need more study, including parking, the narrow Main Street bridge at Trail Creek, traffic light coordination, and the Warm Springs corridor from Lewis Street to Main Street, which Birdsall agreed is "a mess."

Ketchum resident Mary Jane Conger advised council members that they should carefully consider all options suggested.

"The worst thing the city council can do is nothing," she said. "Everything should be on the table. We’ve heard an awful lot of this before…and nothing’s been done about it. Please, at least do something with this."

 

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