Drivers going through the construction zone on Interstate 94 between Maple Grove and Rogers are following the vehicles in front of them too closely, and it’s causing havoc.

From July 1 to Sept. 30, police responded to more than 100 crashes in the work zone stretching from the I-94/694/494 interchange to Hwy. 101. Drivers “following too closely,” also called tailgating, was cited as the main factor by far in the crashes, according to data from the Minnesota Department of Transportation.

That raises the question: Just how close is too close?

The Minnesota driver’s manual doesn’t specify a distance but says drivers must “maintain a safe distance between your vehicle and the vehicle in front of you.” It also says motorists must be far enough back to be able to stop or turn to avoid a collision.

Applying the so-called “3 second rule” to keep a safe distance between your car and the vehicle ahead of you isn’t just sage advice trumpeted by driver’s ed instructors — it’s in the driver’s manual.

Here’s how it works. Drivers are to look ahead and choose a reference point such as a telephone pole or sign. When the vehicle ahead of you passes the reference point, count to three. If you pass the reference point before you are through counting, you are following too closely.

The scenario played out in Maple Grove on Sept. 11, when a westbound driver slowed in congestion near Maple Grove Parkway and was hit from behind. That set off a chain-reaction crash involving five motorists, according to a State Patrol report, and spawned a mileslong traffic jam.

Nearly 42% of wrecks that occurred during the three-month period involved drivers not leaving enough space between vehicles. The second leading cause was drivers who failed to stay in their lane, resulting in 20% of the crashes. Motorists who drove in a careless or negligent manner, or improperly turned or merged in traffic, were the other main causes, MnDOT data showed.

With eastbound lanes separated by a concrete median between Hwy. 101 and the I-94/494/694 split, driving on I-94 in the northwest suburbs has been a challenge. Two lanes are designated for through traffic and one for access to local roads. Lane shifts and temporary closures are in place for westbound drivers. In both directions motorists are using 11-foot lanes, a foot narrower than usual, without any shoulders.

MnDOT is spending $350 million to rebuild bridges and resurface deteriorating pavement. The agency also is adding a fourth travel lane between Hwy. 610 in Maple Grove and Hwy. 101 in Rogers to eliminate bottlenecks that have formed since Hwy. 610 was connected to I-94 three years ago, and building a new interchange east of Brockton Lane.

MnDOT sent out mailings and e-mails, posted videos on its website and put up billboards and digital roadside signs to prepare drivers for this summer’s construction and educate them about driving through the work zone. The agency also lowered the speed limit from 70 mph to 60.

The barriers will be taken down and the freeway converted back to its normal configuration by early November, MnDOT spokesman David Aeikens said.

In the meantime, he said, “people need to pay attention, keep their eyes on the road and be prepared to stop. People need to drive with care and caution here just like in any work zone.”

Sounds like a good way to save your fenders.

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