Northbound traffic at the Maine Turnpike toll plaza in West Gardiner is seen in this May 7, 2012, file photo. Credit: Brian Swartz

The Maine Turnpike Authority is owed more than $800,000 in unpaid tolls dating back to 2013, according to a recent data analysis.

Most of the money — more than $600,000 — is owed by out-of-state vehicles, including commercial trucks, the Portland Press Herald reported Sunday. The news outlet conducted an analysis of Maine Turnpike Authority data.

The unpaid tolls makes up a tiny fraction of the authority’s $140 million annual toll revenue, but the actual amount owed could be much higher because tollbooth cameras aren’t able to read a license plate that’s dirty, obscure or missing, the turnpike authority said.

“Your guess is as good as mine in terms of trying to put a dollar value on those 200,000 plates that went through, in some cases vehicles without plates,” said the turnpike authority’s executive director, Peter Mills. “We don’t know where to begin to identify the car or vehicle or try to collect from them.”

Most violations are unintentional, caused by an improperly placed transponder or a license plate that hasn’t been updated in the transponder system, Richard Somerville with the turnpike authority said. The agency only pursues violators who have skipped payments of at least three tolls in six months.

For chronic violators — dozens or hundreds of times at the turnpike without paying — the authority may send payment notifications, tack on fines and possibly ask the Maine Bureau of Motor Vehicles to issue a suspension.

Between 50 and 100 registration suspension requests are sent to the bureau daily. Most violators pay what they owe, the turnpike authority said, and only 4,600 Maine registrations were suspended for toll violations in 2018.

The bureau also has the power to suspend out-of-state violators, but it can be difficult to identify the drivers and suspend their registration because other states and Canada have rules about sharing driver information.

Maine, New Hampshire and Massachusetts have an arrangement under which the three states can request that agencies prevent re-registration of vehicles that owe tolls.