October is shaping up to be a nightmarish month for commuters who use Hiawatha Avenue with lane closures, detours and even a 10-day shut down of busiest segment of south Minneapolis thoroughfare starting Friday.

But the short-term pain will come with a long-term benefit of improved traffic flow as the city installs new technology that is expected to better coordinate traffic signal cycles that often are disrupted when light rail trains pass. That often leads to bottlenecks and long delays for motorists trying to make left turns or access side streets.

"We get more [311] calls about that than anything else in the city," a smiling Minneapolis City Council member Sandy Colvin Roy said following a presentation at Tuesday's Transportation and Public Works Committee meeting to announce the installation, which begins on Wednesday. "I feel like we should have balloons, but we will wait until November when we are done."

The $1.1 million project includes installing 160 underground traffic sensors at seven intersections between 26th and 50th streets along with control units that will regulate traffic flow. The current units reset to the beginning of their cycle when a train passes, and sometimes phases get skipped for two to three cycles, said Allan Klugman, a senior engineer with the Minneapolis Traffic Parking Service Division. The new units will be able pick up where they left off and have the ability to accelerate the cycle and award a green light to vehicles that have been waiting the longest.

"The main advantage is that delays on side streets and left turn lanes will be greatly reduced," Klugman said. "People sometimes wait 8 to 10 minutes; we know it because we have seen it. Drivers won't miss a phase because a train goes by. This will bring minutes of savings."

New signals also should improve navigability for bicyclists and pedestrians, Klugman said.

Until the project is finished, the 23,000 motorists who use Hiawatha on the south end and the 32,000 to 37,000 who use it on the north end are in for a tough go. Crews will shut down the northbound lanes of Hiawatha between 50th and 26th streets Saturday and Sunday to install sensors. They will close the southbound side Oct. 20-21 for the same reason.

Those closures are in addition to lane restrictions and detours that will go into place as Xcel Energy buries two high voltage wires that will connect to two substations. Starting Friday night, Hiawatha will be closed for 10 days between 26th Street and Lake Street.

Metro Transit light rail trains will operate as normal while the road work is done.

With high volumes of traffic turning onto and off Hiawatha combined with the frequency of passing trains, the four-lane state highway has called the most complex corridor in the country by traffic engineers. It's also been bane of motorists since trains began operating in 2004.

"This is fun for those of us who like traffic and technology," Klugman said. But the main benefit is that "by the end of the year much better operation along Hiawatha."