Van Zandt County Fire Marshal Chuck Allen said the annual event is hosted by the East Texas Council of Governments and switches cities each year.
Between 400 and 500 emergency responders are estimated to flood to the area over the three days, from today through Thursday.
Participants will practice responding to a structure collapse, active shooter scenario involving biohazard materials or explosives, wide area search and rescue, rescuing a person from a hazardous wreck, impending dam breach, residential search and work to rescue someone submerged under Lake Canton.
“They are going to be put in real, life-threatening circumstances but in a training excise only,” Allen said.
Allen said the group also will test the city's First Monday Emergency Response Plan at 7 a.m. today with a simulated tornado coming through the First Monday grounds.
Allen said the city created the plan a few years ago and is excited to have a chance to test it.
“A lot of people don't realize the city of Canton can become the tenth largest city in the state of Texas during a first Monday weekend,” he said adding the death toll of a catastrophic event could be in the hundreds of thousands of casualties because many of the participants do not have a safe permanent shelter to take cover in.
The city invited mutual aid partners from Dallas to participate in the event.
Simulated casualties will flow into area hospitals, including East Texas Medical Center in Tyler and Trinity Mother Frances Hospitals and Clinics.
John Moore, director of public relations for Mother Frances, said the hospital is required by law to participate in drills annually, and the practice has come in handy when it came to hurricane response.
Moore said the hospital is kept in the dark until it is time to activate the hospital in the drill.
He said the drill will not affect patient care, but medical supplies in closets may dwindle, and generators may need to come on as part of the simulation.
“It would be good for (the public) to be aware they will probably see more activity, more emergency vehicles and you would treat that as you would any other day, and that would be to move over and let those vehicles pass,” Moore said.
Allen added that residents should be aware the active shooter exercise will be about 5 p.m. Thursday at the Van Zandt County Courthouse in Canton.
“We are testing out a plan. … They may see their weapons pulled out,” he said. “If you are not participating in the drill, you need to keep your weapons at home and avoid the (First Monday) grounds and the courthouse.”
Training exercises will be in Grand Saline, Lindale, Canton, Lake Canton, Lake Tawakoni, Hideaway Lake and Lindale.