PLYMOUTH — Minnesota has started construction on a $68 million highway project scheduled to run through 2016.

The state will add a third general-purpose lane to both directions of Interstate 494 in Plymouth. Three highways come together in the area’s Fish Lake interchange. Three lanes currently narrow to two in Plymouth for six miles.

Minnesota Department of Transportation earlier this year identified $50 million in savings from other construction projects to help fund the job.

Mayor Kelli Slavik said she expects commuters will experience frustration over the next three years. She says the new lanes will decrease bad congestion and commute times.

About 95,000 vehicles use the segment each day.

Drivers can expect some night and weekend road closures through November. No full closures are planned.