If you've driven along Hwy. 10 through Arden Hills and Mounds View over the past few weeks, you may have seen Minnesota Department of Transportation crews installing new guardrails and a cable median barrier.

It's all about improving safety along the north metro highway between Interstate 694 and just shy of Interstate 35W, a roughly 2-mile stretch that some drivers often refer to as "the Diagonal." And it's about removing a temptation that was too much for drivers.

As you may recall, from 2011 to 2013 the heavily traveled section of Hwy. 10 was resurfaced at the same time MnDOT rebuilt the Interstate 694 and Hwy. 10 interchange to improve traffic flow. A major pinch point on Hwy. 10 at County Road 96 was removed when traffic signals were replaced with an overpass and exit and entrance ramps.

When the project was completed, Hwy. 10 resembled a freeway, except there were a couple of left turn lanes and crossovers along the stretch that MnDOT left in place to give motorists easier access to places such as the Big Ten Tavern and Scherer Brothers Lumber Co. Even though signs at the two locations told motorists that U-turns were not allowed, too many drivers disobeyed and used the paved median openings to make illegal and dangerous U-turns in front of oncoming traffic. That led to "some close calls," said MnDOT spokesman Kent Barnard.

When signals were operating at County 96, often there would be enough of a break in traffic to allow drivers to safely cross the highway and even make a U-turn, but since the signals were removed, traffic sails by at speeds of 55 miles per hour and there are no breaks in the traffic flow. So the agency in June took out the left turn lanes and the pavement crossovers, and is permanently blocking them as part of this month's cable median barrier installation.

15 fatal crossover crashes a year

Motorists heading north on Hwy. 10 can still reach the Big Ten Tavern and Scherer Brothers Lumber and a frontage road on the west side of Hwy. 10, but it will take a bit more backtracking. Drivers will have to head up to County Road H, where there is a full interchange, to turn around and then go back south on Hwy. 10.

The new cable median barrier is expected to be completed by the end of the month. And when it is, the barrier will be part of an ever-growing network of the devices aimed at stopping cross-median crashes. There are about 15 fatal crossover crashes a year on four-lane divided highways, according to the Minnesota Department of Public Safety.

Just last month, two truck drivers were killed in such a crash when Michael R. Kalvig, 47, of Glenville, Minn., was heading east on Interstate 90 near Novine in southeastern Minnesota when he suddenly crossed the median and hit an oncoming semitrailer truck traveling westbound, which was driven by Abdulhafiz U. Hussein, a 37-year-old Roseville man, the State Patrol said.

Cable median barriers first appeared on Minnesota roads in 2004 and as of January 2016 covered 190 miles of highways in the metro area and 347 miles in greater Minnesota.

At an installation cost of $140,000 to $150,000 per mile, MnDOT continues to add the barriers along highways prone to crossover crashes. Studies have shown that the barriers can reduce fatal crashes by up to 95 percent. MnDOT estimates the barriers have saved 80 lives over the past 12 years.

Follow news about traffic and commuting at the Drive on startribune.com. Got traffic or transportation questions, or story ideas? E-mail drive@startribune.com, tweet @stribdrive or call Tim Harlow at 612-673-7768.