The Drive: Road work keeps drivers griping about cone zones

Monday is the first workday that motorists in the south metro will have to deal with construction on the Bloomington Ferry Bridge that will squeeze Hwy. 169 traffic into a single lane in each direction for the next month.

They are not likely to get any sympathy from commuters who travel on Interstate 694 in the north metro, where lanes were reduced for more than a month. Highway 36 drivers on detour since mid-June and those who have endured disruptions on I-35E in Eagan probably won't shed any tears, either.

The Minnesota Department of Transportation is in the middle of an ambitious metro construction season involving 87 projects. While many drivers understand the need for repairs, the ubiquitous cones, barrels and detours have patience wearing thin and tempers turning as hot as a July heat wave.

"I'm fed up with construction and this horrible Twin Cities traffic," said Renee Knutson. "Let's hope they realize how frustrated we are during rush hour."

Much of motorists' ire comes because long stretches of roads are blocked off and there isn't any work being done. That makes Lori Rilling "cranky."

Cones are set up well before the actual work zone begins to give drivers ample time to get out of the lane that is about to close. That space also provides a buffer zone to protect construction workers and prevent equipment from obstructing traffic, said MnDOT's Kent Barnard.

The amount of traffic on a road will dictate how long and wide lane closures must be. MnDOT uses the "Minnesota Manual on Uniform Traffic Control Devices." The multi-page document spells out where barrels must be placed, how far apart they must be, and how far before and after a work zone they must be positioned. Even if a work zone is only 200 feet long, busy freeways such as 694 and 35E require longer buffer zones than less-traveled highways.

Once a construction zone is established, lane restrictions often remain in place for the duration of a project, even in areas that appear to be finished. That's because it's expensive and labor intensive to set up and take down barrels. Barnard said it can take as long as six to eight hours to configure a work zone by the time barricades are set up and new pavement markings are put down.

MnDOT contracts with construction companies to complete various parts of a job. One firm might repair the steel rebar while another pours the concrete and a third company be responsible for culvert repair. While one job might be complete, another likely is not. Motorists might not see anybody working in an area where concrete has been poured because it takes as long as 72 hours for it to cure.

Another reader asked why construction projects often take months to complete since the I-35W bridge was rebuilt in just over a year after its collapse in August 2007. On that job, workers were on the job round the clock. "That is kind of the gold standard, and you can do that if there is enough money," Barnard said.

Contractors pay by the day for lane closures, so they do have an incentive to finish quickly and get the roads open, Barnard said.

Still, Rob Jones lamented, "It's frustrating when a road is under construction and nearly all of the alternative routes are under construction, too."

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.