City officials and residents in Edina had hoped that midblock stop signs and barricades that slim down the road so only one vehicle can snake around them at a time would be enough to keep Hwy. 169 drivers from cutting through the Parkwood Knolls neighborhood.

They weren't.

So starting Monday, the city is enacting more extreme measures to combat the huge amount of regional traffic that has opted to use residential streets rather than following MnDOT's prescribed detour sending drivers on Crosstown, Hwy. 100 and I-494 while the agency replaces the Nine Mile Creek bridge between Bren Road and the Lincoln Drive/5th Street exit.

Electronic signs now tell drivers that they'll be able to get out of the neighborhood during rush hours, but not without taking the long way around. Southbound drivers coming off Hwy. 169 at the Lincoln Drive exit won't have access to Malibu Drive and Parkwood Road between 7 and 9 a.m., and northbound drivers won't be allowed to go any further than Lincoln Drive and Dovre Drive between 4 and 6 p.m.

Before the bridge closed on Jan. 23, about 1,000 vehicles a day passed through the intersection of Parkwood Road at Parkwood Lane. After the closure, the number jumped to 5,100, which brought bumper-to-bumper traffic so thick that residents in the normally quiet neighborhood had trouble backing out of their driveways and found it perilous to go for a walk. The midblock stop signs, called "traffic calming" measures, went up Feb. 2, and traffic volumes fell to 3,800. But the signs only exacerbated the problem, residents said.

"Our quiet residential road has not only turned into a freeway as 169 traffic is diverted through our neighborhood, but it's traffic comprised of aggressive and angry drivers that run stops signs, speed around school buses and otherwise show no regard for the safety and well-being of anyone other than themselves," wrote Erik Hinkie in an e-mail to the city. "The current traffic calming system has only created more aggressive drivers while adding considerable time to our commutes out of our neighborhood."

The Edina City Council gave traffic engineer Chad Millner authority to take additional steps to address the traffic problem, so the exit-only plan was the next option.

"It will be inconvenient," Millner said. "We can't just put a sign up and expect people will follow it. Residents will have to adjust their routes."

St. Croix Bridge update

Here is an upside to the warm weather we've had this winter. Crews have made good progress on the St. Croix bridge, which MnDOT says now is on target to open to traffic in August. That's a month or two earlier than had been expected.

Earlier in February, crews completed the deck structure on the $646 million Hwy. 36 bridge connecting Oak Park Heights and St. Joseph, Wis., said Project Manager Michael Beer.

MnDOT still has to install expansion joints, grade approaches, put in lighting and apply a chip seal coating to the surface before the first cars can cross, and "that can't be done until it gets warmer," said MnDOT spokeswoman Kristin Calliguri.

Once the new St. Croix Crossing opens, it will replace the aging Stillwater Lift Bridge, which will become part of a hiking and biking trail.

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.