Police in Thunder Bay, Ont., say they're stopping more suspected drunk drivers than in previous years, but the reason isn't immediately clear.

According to Cst. Mark Cattani, police "intercepted" roughly 120 to 130 suspected drunk drivers each year from 2013 to 2015. But in 2016, that number jumped to about 170 and police are projecting this year's statistic will look very similar, he said.

Cattani specified those numbers only include instances where the driver is stopped due to suspicion of driving under the influence of alcohol, not other drugs.

"The real hard part is determining what is causing those numbers to increase," he said. "Is it a simple matter of we're getting better at intercepting it or the community is calling in more cases that we're catching or is there actually more impaired driving?"

"Is it happening more or are we catching more? That's the real question."

Cattani said charges aren't laid in every case where a driver is stopped, possibly due to "a circumstance where a charge isn't appropriate or where there just isn't enough evidence to bring that charge to court," but that police do lay charges in "the overwhelming majority" of instances.

Still, he said, those numbers don't tell the whole story of how common it is for people to get behind the wheel when they've had too much to drink.

"We catch a low percentage of what's actually out there — we know that, all police services know that — we don't get the majority of impaired drivers," he said.

Don't Impair Your Future Thunder Bay police

Thunder Bay police officially launched their public awareness campaign against drinking and driving on Nov. 6. (Thunder Bay Police Service)

This comes as police said they are preparing for the holiday season, a time that "brings out more festivities and more socializing so it goes hand-in-hand with that there will be more drinking and driving," said Cattani.

Police have also launched a public awareness campaign to keep the issue in the spotlight. The Don't Impair Your Future campaign officially kicked off November 6.  Cattani said the initiative's messaging will appear on the backs of city buses and on the electronic billboard outside Port Arthur Stadium.  In addition, police have produced a pair of videos that have been uploaded to social media.

Another reminder, Cattani said, will be the number of RIDE checks on city streets in Thunder Bay over the next two months.