City of Dickson to Consider Tornado Siren System

The City of Dickson is considering the installation of an outdoor warning system that could alert citizens to possible tornadoes or other severe weather.

At the July 15 Finance and Management Committee meeting, Kathy Hovis of Sirens for Cities, Inc. and Major Todd Christian of the city’s Office of Emergency Management presented proposals for an outdoor warning system with three or nine pole-mounted sirens, with price tags of $112,000 and $300,000.

The system would consist of omnidirectional sirens mounted on 45-foot wooden poles that would alert at 127 decibels with an estimated coverage of 1.5-3 square miles for outdoor warnings.

Hovis and Christian said the likelihood of being awakened by or hearing the sirens indoors depends on several factors, including proximity to a siren, noise inside the building and weather conditions.

“So, if they’re in bed asleep, depending on how low the clouds are, they may or may not hear it,” Christian said. “In doing some research, that’s what I hear the most complaints about through the other EMA or OEM directors, is that, when they do (activate) in the middle of the night or something like that, the people indoors will call and say, ‘Well, I never heard it.’… They’re designed for outside warning devices. If you hear it in the house, you just get lucky that you heard it in the house. But I don’t think that it’s going to wake you up at 2 or 3:00 in the morning.”

“I would say it depends on how close you are to the siren,” Hovis said. “But within that radius, you have a pretty good chance of hearing it… When it’s cloudy and stormy, the sound is nearer the ground and they’re going to hear more than they will the day you test them,” Hovis said. “And you should test them every week.”

Hovis said the siren systems are intended to be a secondary notification, with most people having access to weather forecasts able to anticipate dangerous weather and by using television, radio and telephone alert services can be forewarned and listening for the sirens.

“This is a redundancy. This is something that you put in as a backup,” Hovis said. “Because people are supposed to be weather-aware… If you’re putting the message out already and they hear it, they’re going to be awake to listen for it.”

Under the Sirens for Cities proposal, the Sentry Sirens cost $23,874.81 each with an installation cost of $7,500 apiece and $18,250 for the software system to operate the sirens. Those prices do not include the acquisition of any property for placement of the sirens or the installation of electric service to the sirens.

Hovis said the sirens have a minimum of 30 cumulative operating minutes of battery power should electricity be knocked out, meaning the sirens could alert in three-minute bursts up to 10 times before power is restored.

Mayor Don L. Weiss Jr. said the sirens could be placed on city-owned and operated sites such as fire stations, J. Dan Buckner Park, Henslee Park or Tennsco Recreational Complex so the city would not have to acquire additional property.

Acting City Administrator David Travis said a review of the proposals determined three sirens would not provide adequate coverage and the nine-siren proposal includes significant overlap.

“So, we were looking at maybe placing one at all three of our fire stations. That gets us one over around Ridgecrest (Drive), one over close to the industrial park there close to Tennsco Park, it’s outdoors, and then one here at Station 1 for the downtown people,” Travis said. “Then, there at Buckner Park or Henslee Park. We were looking at the heavily populated outside areas, where people go spend time outside.”

Travis said he and the mayor looked at the possibility of 4-6 sirens to cover the major outdoor areas and Hovis said once locations are identified, Sirens for Cities can devise a coverage map based on those sites.

Mayor Weiss asked the council to allow Major Christian and Mr. Travis to assemble a proposal with potential locations.

“I don’t think three’s enough,” Mayor Weiss said. “I do think, in this day and time, especially as much traffic as we have in our parks and our downtown area, that the need is there nowadays. What I would ask is that you allow those two to put their heads together and see if they want to come back with four, five or six or seven and then we can build on that or take away from that.”

Hovis said once the initial sites are in place, the system can continue to be expanded with new locations.

The council members present agreed to move ahead with creating a proposal to bring back to a future meeting. No timeline or deadline for presenting a plan was discussed.