Minneapolis plans to refurbish aging 10th Avenue Bridge over Mississippi River

After 90 years, things start to wear out. That's the case with the 10th Avenue Bridge over the Mississippi River parallel to Interstate 35W in downtown Minneapolis.

This year and next, the 2,174-foot-long bridge will be refurbished and updated to include a two-way protected bikeway and sidewalks on both sides, said Don Elwood, director of transportation engineering and design for the city of Minneapolis.

The reinforced concrete structure with its seven distinctive arches opened in 1929 and connects 10th Avenue SE. on the east side of the Mississippi River with 19th Avenue S. on the west side. The bridge, which carries about 10,000 vehicles and 2,000 pedestrians and bicyclists a day, "is an important connector for Minneapolis, linking the University of Minnesota and downtown Minneapolis," Elwood said.

It also has a number of problems. The bridge's expansion joints are leaking. So are its drainage elements, which has led to corrosion and deterioration of concrete components, particularly in the arches and support columns that have cracks and exposed rebar in places.

The sidewalks and bridge railings were replaced in the 1950s, and the driving surface was replaced in the 1970s. But not much has been done over the past 45 years.

Starting this fall, the city of Minneapolis, which owns the bridge, will spend $43 million to get it back in shape. That includes restoring the arches, columns, floor beams and piers and a new deck.

There will be effects on traffic during construction, Elwood said, especially in 2020 when the bridge is shut down for a year and drivers are put on detour.

Currently, there are two travel lanes and a bike lane in each direction, plus a sidewalk on the east side.

When the bridge reopens, drivers will see a much different configuration. Motorists will have one northbound and one southbound lane. There will be sidewalks on both sides of the bridge and a two-way protected bikeway separated from traffic on the east side.

None of the work will alter the overall appearance or integrity of the bridge, which was designed by Norwegian engineer Kristoffer Olsen Oustad and in 1989 was placed on the National Register of Historic Places.

Get ready for four years of upheaval on Hennepin Avenue in downtown Minneapolis, and that's no matter if you walk, bike, ride the bus or drive.

The first phase of the massive reconstruction project gets underway Monday when utility work begins between 7th Street and 12th Street. With it will come noise, dust and traffic disruption.

Metro Transit bus routes 4, 6, 12, 61 and 141 will move to Nicollet Mall.

Traffic on Hennepin will be reduced to one lane in each direction, and left turns on and off Hennepin in the construction zone will not be allowed. Streets crossing Hennepin will be reduced to a single lane, and pedestrians will be sent on detours.

In short, things will be a lot like they were when Nicollet Mall was redone a few years ago.

When everything wraps up in 2022, Hennepin from 12th Street to Washington Avenue will have new sidewalks, space for enhanced bus stops that can accommodate bus rapid transit service, protected bike lanes and new pavement.

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