ST. PAUL — On more of Minnesota’s two-lane state highways, motorists could soon be free to drive above 55 — legally.

As part of an expansive budget bill signed into law last week, state lawmakers nudged transportation officials to boost the speed limit to 60 miles per hour on lane miles where it can “reasonably and safely” be done. By 2019, traffic engineers must examine every mile of road with a 55 mph limit and determine if it is prudent to go higher.

It’s an enormous undertaking. There are 6,771 miles on two-lane/two-way state highways now covered by a 55 mph limit. Officials figure they’ll get through about one-fifth per year, starting as soon as next month. They will analyze each stretch’s crash history, design, lane width, sight lines and ditch slope.

“The fact we’re studying the roads does not mean you can jump to the conclusion that all roads will be raised to 60 miles per hour,” said Peter Buchen, assistant state traffic engineer at the Minnesota Department of Transportation.

But the agency has been moving in that direction. In 2005, the department bumped the limit to 60 mph on 791 miles of two-lane highways and added another 750 miles last year. Buchen said those were prime candidates — straight, wide-open stretches with clear sight lines and low incidence of crashes. He said limits on hillier, curvier highways probably won’t budge.

It can take up to a year from the time the analysis starts to the placement of a new sign with a new number.

Sen. Torrey Westrom, R-Elbow Lake, said he thought MnDOT was moving too slow on its own and pushed for the requirement that every mile get studied within five years. He said his constituents in Greater Minnesota generally travel further for work, shopping and recreation and want to be able to move about faster.

“Most people are driving 60 miles per hour already,” Westrom said. “It’s a comfortable speed.”

The fact people are giving themselves a grace period above the speed limit already is what bothers some about the anticipated jump.

“If they raise the speed limit to 60, they’ll go 70,” said Sharon Gehrman-Driscoll, director of the advocacy group Minnesotans for Safe Driving, who was surprised to hear the proposal became law as an overlooked clause in a 577-page bill. “We’re raising the chances of much more severe crashes.”

According to the Department of Public Safety’s annual “Crash Facts” reports, illegal speed was cited as a factor in 214 fatal crashes resulting in 243 deaths. Speeding is the leading factor in single-vehicle crashes and one of the most common factors in multi-vehicle crashes.

But traffic engineers say there can also be a benefit to raising limits because it fosters more consistent speeds. Newer roads are built with features that have broader shoulders and extra room for recovery if a driver loses control.

Lt. Eric Roeske of the Minnesota State Patrol said troopers are ready to react to whatever transportation officials decide.