The DOT’s Mark Hansen says, this summer, most of the employees monitoring traffic will be stationed in an area north of Highway 30 and west of Interstate 35.
“We’ll have manual counters sitting at roadway intersections, counting and classifying vehicles, and looking at the turning movements, literally all across northwest Iowa,” Hansen says. Many employees will spend peak hours between 7 a.m. and 6 p.m. at one location counting the morning, noon, and evening traffic.
“One thing we look at is the turning movements at a particular intersection. This is important, for instance, if there is a lot of traffic turning left — and if the city has a left turn lane there — we may need to extend that left turn lane so more cars fit in the cue or we double that left turn lane to double the capacity there,” Hansen says.
In addition to the manual count each summer, the DOT also employs automated traffic recording equipment statewide. “We do have roughly 180 automatic traffic recorders across the state that are counting traffic 24 hours a day, seven days a week for us, to help us establish trends in the traffic patterns,” Hansen says.
Another data collection method involves a van with two mounted cameras that collect 200 images per mile. This year, that van is covering the northern half of the state. Hansen says all of the data collected by the DOT helps the agency plan the future of Iowa’s roadway system.