More than 600 people have died on Colorado roads in 2017 as of Monday morning, putting the state on track to surpass last year’s grim tally amid efforts from the Eastern Plains to the mountains to cut down on traffic fatalities.

The Colorado Department of Transportation said the 604 road deaths this year mark a roughly 3 percent year-to-date increase.

In 2016, 608 people died on the state’s roads — an 11 percent increase over 2015 and the highest total in more than a decade.

“The way the data is trending, we know that fatalities are likely going to be up this year if the trend holds,” said Sam Cole, CDOT’s traffic-safety program spokesman.

Cole said preliminary data show an increase in deaths from crashes involving impairment and people not being properly restrained with a seat belt.

As of Dec. 12 — the latest date for a detailed breakdown of the current number of deaths — CDOT data showed 220 people died in impairment-related crashes. El Paso County had the most roadway fatalities — 73 — followed by Adams County, Weld County and Denver County, respectively.

By city, Denver has had the deadliest roads so far this year, with 44 deaths. Colorado Springs was next, followed by Aurora and Pueblo.

In September, a single crash in southeast Colorado involving four vehicles killed four people.

Cole said officials are still waiting for end-of-year data to be compiled before taking a hard look at what has caused the increase in deaths.

“We don’t really dive into analyzing the year until we get all the data in,” he said. “We’re still waiting on different reports from the counties and the coroner’s offices.”

Cole pointed at the decrease in motorcycle deaths and the decline in the year-over-year increase rate of people killed as positives.

In January, CDOT’s then-executive director, Shailen Bhatt, blamed last year’s increase in road deaths on an “epidemic of distracted driving.”

The Gazette reports that officials are blaming crowded roads for Colorado Springs’ record-breaking year for crashes involving fatalities. As of Saturday, when a Colorado College campus safety officer died in a wreck near Monument Valley Park, the number of fatalities hit 38 for the year.

Denver has embarked on a plan to try to end traffic-related deaths by 2030. In 2015, state officials made a pledge to achieve a year with zero traffic deaths.