Cookeville will prioritize the expansion of traffic signal battery backups to maintain full intersection functionality during power outages.
Public Works Director Mary Beth Elrod said the city has identified 36 future locations for these backups along major corridors and thoroughfares. Elrod said the plan involves budgeting for approximately one-third of these intersections each year over a three-year period to stagger the replacement life of the equipment.
“Currently when there’s a power outage, you’ll see the stoplights go into flash mode where they’re just flashing yellow and red, and people are supposed to use that intersection as a four-way stop,” Elrod said. “What we see is, that doesn’t always happen in the larger intersections, because people just don’t know how to handle a large intersection with a four-way stop.”
Elrod said a recent outage at Highway 111 and I-40 required police to be dispatched to flag traffic while the signals were in flash mode after an outage. City Manager James Mills said last week the issue caused a major disruption that the city needed to fix.
Elrod said the city currently has nine battery backups installed across approximately 76 total intersections. Elrod said the proposed budget for the next fiscal year is between $200,000 and $250,000 to equip 10 to 12 additional intersections.
“When the power goes out, we would like to have the battery backups fully run the intersection for at least an hour,” Elrod said. “That takes a lot of electricity and power on a backup battery, so it can’t run it for an extended period of time. But most of our power outages in town, we are fortunate that most of the time a power outage doesn’t last longer than an hour.”
Elrod said current quotes for the equipment are approximately $10,000 per intersection. Elrod said the city is investigating whether to use a proprietary brand or seek other suppliers through statewide or purchasing contracts.
“I think it only took 30 minutes for the Energy Department to get that power back up and running, but still that did cause 30 minutes worth of a little bit of chaos at those intersections,” Elrod said. “And so that would eliminate having to send out additional personnel or on-call crews as long as those battery backups can keep the intersection running for about 30 minutes to an hour.”
Elrod said the priority routes for the new backups include Willow, Jefferson, Highway 111, Tenth Street, and Broad Street to ensure emergency access to the hospital.
“So that’s kind of the industry standard with traffic signals, but we want to invest in battery backups and the city council, and Cookeville wants to take that as a priority,” Elrod said.
Elrod said the city will continue gathering information for the council to make a final decision on the best way to move forward.