Arizona did not see its usual monsoon season in 2020, but the system set up to protect motorists driving along Interstate 10 during weather events has proved its worth, officials say.

The $72 million dust detection warning system lining I-10’s mileposts 209 and 219 in Eloy and Picacho Peak kept drivers safe while moving through the corridor with low visibility.

Researchers gathered noticeable measurements from one 20-minute storm, which led to the system lowering the variable speed limit signs to 35 mph because of visibility dropping to less than 300 feet, ADOT said.

The system then recorded drivers slowing down to at least 45 mph, “a big drop from the normal 75 mph limit,” ADOT said.

When entering the corridor motorists see overhead electronic message boards alerting them to blowing dust and to slow down.

Several programmable speed limit signs are placed every 1,000 feet near the corridor’s entrance and shift between 75 mph to 35 mph depending on the weather event. Additional signs are placed 2 miles apart.

Motorists will also see the long-range weather X-Band radar dish as part of the system, sitting atop a 22-foot-tall pole at the Arizona 87 interchange that can detect storms more than 40 miles away.

An important part of the system is ADOT’s Traffic Operations Center in Phoenix.

It’s the central monitoring location using closed-circuit cameras to identify conditions along the roadway and potentially more storms in the distance.

Tohono Chul Park, 7366 Paseo del Norte, is open every day. Get tickets online only at TohonoChul.org. October 2020.

“We do know that the system is working — it is doing what it’s supposed to,” said Kevin Duby, ADOT’s statewide road weather manager. “Our next step is to take the data we have to evaluate and determine the efficiencies of the system to improve performance.”

The dust detection system has been in officials’ minds since 2016 as researches reported accumulated crash data from 2010 and 2015 detailing weather events impacting the 10-mile corridor.

Their data showed 83 dust-related crashes where over 50% occurred within a half-mile of each other. It led officials to address the concerns with the detection system.

ADOT’s was recognized this year by the National Weather Service as a “Weather Ready Nation Ambassador of Excellence” for their efforts and innovations to improve driver safety during poor weather events.

“ADOT continues to become more resilient to the wide range of weather hazards that impact Arizona roadways including winter storms, dust storms, wildfires, and flash flooding,” the weather service said.

With the recognition, the two agencies will continue collaboration to “strengthen partnerships with external organizations toward building community resilience in the face of increasing vulnerability to extreme weather and water events,” according to the Weather Service.

Down the Road

Closure of eastbound I-10 exit ramp to Houghton Road: The eastbound I-10 exit ramp to Houghton Road will cause motorists to use an alternate route this week.

Crews will close the ramp from 9 p.m. to 5 a.m. nightly through Thursday, Nov. 12, as they complete interchange work.

Motorists should use Rita Road as an alternate route.

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Contact Star reporter Shaq Davis at 573-4218 or sdavis@tucson.com

On Twitter: @ShaqDavis1