Having fallen into disrepair decades ago, the Walnut Street Bridge was renovated and given a new lease on life by Chattanooga citizens, becoming an iconic historic structure for residents and tourists
Such an attraction isn't cheap, though. The bridge will receive a $14 million rehabilitation over the next five years, and officials are proposing a $4.05 million light system on top of that in this year's capital budget - a $2 million increase from the city's original cost prediction in March.
The lights, designed by Canada-based Moment Factory, use "data responsive lighting design" that would respond to people walking on the bridge and the flow of the Tennessee River underneath it. The movements would be depicted by color variations and "ripples of light" that gradually climb and descend the bridge's exterior.
After six months of meetings and public comment, city Public Art Committee director Katelyn Kirnie said the city would pay $2 million for the system from hotel and motel tax revenue. The other $2.05 million would come from "external" sources, or private donors.
City staff doesn't believe that will be a problem for a project that will "enhance" the iconic bridge and define it as an "identity-maker."
"We are committing to it because we are confident it's the right direction," Kirnie said. "We will be actively fundraising and we are confident we have a number of parties interested."
At a city council meeting in March, Kirnie said there was a budget of $2 million to update the "very outdated" lighting as part of the makeover. After looking at options and choosing one that Kirnie said "pleased everybody," the concept came in at $4.05 million.
Documents show Moment Factory proposed two options. The "base option" would have cost a little more than $3 million. An "enhanced option," at nearly $9 million, would be data responsive and include pixelated light shows, among other features.
There have been multiple meetings since December to discuss the light system and hear from the public and from people who live nearby. In April, residents of the Museum Bluff Condos voiced concerns over the pixelated light shows as being "intrusive" and "inappropriate" for the historic and natural setting, according to meeting notes.
After the Chattanooga Public Art Committee said it would prefer the base option, Moment Factory created a design focused on the base option, with added features to highlight the bridge's exterior and historic architecture and to make it data responsive.
Kirnie said there is still a lengthy review process ahead before the light system is a done deal. The State Historic Preservation Office will need to review the design, and it's possible the light system won't be completed until 2020.
"The design is very much a proposed design," she said.
City Councilman Darrin Ledford, who has an art degree and owns ImageWorks Printing + Graphics, said seeing a jump in the final cost is a "great concern" for him.
Ledford said council members will discuss the bridge light system at a budget education session Tuesday.
"I do still have concerns about the lighting package - not necessarily regarding the dollar amount, but the overall concept," Ledford said.
He said he's concerned about possible light pollution and whether the lights could diminish the historical integrity of the bridge. He also wants to know more about the public input to date and in the future on the proposed light system.
The 2019 capital budget includes $5 million for the bridge rehab. Adding the light system would direct more than $9 million to the Walnut Street Bridge in the coming year.
The proposal comes two years after Mayor Andy Berke canceled a contract negotiated by former Mayor Ron Littlefield to buy controllable LED lights from Chattanooga- based Global Green Lighting. GGL installed lights on the Walnut Street Bridge and in Coolidge Park for crime prevention and energy savings.
But after four years of operation, the mayor and EPB, which maintains the city's streetlights, said GGL's lights weren't working as promised and wouldn't have the promised payback in energy savings.
Don Lepard, president of GGL, said the city's decision to scrap the GGL contract in 2016 forced his Hixson factory to close and the new technology to shift elsewhere. Lepard said he proposed a "laser show" experience on the bridge under the Littlefield administration in 2012 but was told the timing was not right and that safety for citizens would have to come first.
The proposal included a laser light show using the backdrop of a fountain spray generated from a barge in front of Ross's Landing, Lepard said. He suggested a small admission fee to cover the costs.
"We even brought in a consultant to discuss the design of the show," Lepard said in an email. "Now doesn't that sound like something a local entrepreneur would suggest? The Chattanooga way!"
According to Lepard, he proposed that private dollars would pay for all of it - not just a portion. The lighted "Big Four Bridge" in Louisville, Kentucky, cost $2.1 million and 75 percent of the cost was covered by private donors.
Louisville is the closest city with a lighted pedestrian bridge comparable in size to Chattanooga's. Louisville's bridge is not data responsive and includes 1,500 LED lights that "bathe the bridge structure with kinetic lights."
Kirnie said the proposed light system for the Walnut Street Bridge also would have LED lights, which will minimize ongoing maintenance.
"We don't have any sophisticated technology in lighting on that bridge," she said. "LED lights have a much longer lifespan and lower maintenance."
City staff trained by Moment Factory could adjust the lights, such as making them red and green for Christmas or red, white and blue for national holidays. Any changes to how the lights respond to the environment would need to be done for hire by Moment Factory, though.
The changes in lighting will not be "abrupt" either, Kirnie said. The light will appear gradually, like a ripple, based on the flow of the river and pedestrian foot traffic, so it shouldn't pose any safety concerns to those driving nearby on the John Ross or Veterans Memorial bridges. The Tennessee Department of Transportation will have to review the new light system, as well.
City staff said they looked at bridges all over the country and the world when trying to decide on a new concept for Chattanooga that enhances the historic feature.
"We are not trying to be anyone," Kirnie said. "We are trying to do something completely unique."
There will be another public input meeting in July to present and discuss the new design but an exact date has not yet been decided. Council members are due for their first vote on the capital budget June 19.
Contact staff writer Allison Shirk at ashirk@timesfreepress.com, @Allison_Shirk or 423-757-6651.