Construction is six months away, but the Ketchum Community Development Corporation and the city of Ketchum are planning for the second stage of the city's Fourth Street Heritage Corridor project, which will be built prior to the Fourth of July holiday next summer.
Members of the Ketchum Community Development Corporation presented a design overview of the blocks between Walnut and First avenues at the City Council's regular meeting Monday, Nov. 19.
The two blocks, one on either side of Main Street, are more complicated than the section of the corridor already completed, and that is because the grades are steeper and require more complex engineering.
Ketchum City Administrator Ron LeBlanc said the city has budgeted $110,000 for this, the second of three phases anticipated to complete the corridor.
"A lot of the design included design factors we're going to be able to carry through all eight blocks," he said, referring to expenses already covered in the second-phase design.
Also at issue Monday was the prospect of heating sidewalk portions of the corridor using "green" ground-source geothermal technology. That would require, however, some additional up-front expense in the form of tighter spacing between tubing that is installed beneath pavers and in digging wells with which to extract and replace the ground water that is used.
"My whole preference for this portion of Fourth Street and the rest is to have the tubes laid as close as possible," said CDC Board President Neil Bradshaw. "Because that gives us the greatest options as far as the kinds of renewable heat we can use."
Using ground-source heat to melt snow on the pavers will be more expensive up-front, but will pay for itself, Bradshaw said.
Bradshaw explained that it would cost roughly $100,000 to install wells from which to draw ground-source water, but "once you've got that your energy is free."
City Engineer Steven Yearsley of Forsgren Associates estimated the cost of two systems would be $216,000. With estimated $10,000 per year savings, the payback period would be 21.6 years.
He said a standard boiler to be used to heat snowmelt systems costs around $150,000 per block.
Ground-source heat works at roughly 100 degrees F. Traditionally-installed boilers pump water at closer to 170 degrees F, and tubing can be more widely spaced.
Dale Bates, also of the CDC, said the group will continue to compile a cost-benefit analysis on the potential for installing a snowmelt system in general on future blocks of the Fourth Street Heritage Corridor, and on ground-source heat in particular. He and the CDC will report back to the city.
"We want to present to you very clear options in the next step," Bates said.
Councilman Baird Gourlay said the city wants to opt for the environmentally friendly option.
"I would like to say I think it's the direction we would like to go," he said. "We just need to see the numbers."
Mayor Randy Hall clarified where the city was with its first phase.
"Last year when we were making these decisions we put too much emphasis on the financial considerations," he said. "We will stress more the environmental side of things in the next phases."
The Fourth Street Heritage Corridor?s second phase, between Leadville Avenue and First Avenue, will be under way this spring. The first phase, above, was completed last summer.
Photo by Willy Cook
