Street crossing
keeps bicyclists, pedestrians moving along Greenway
by Tesha M. Christensen
When the $5.1 million Sabo Bridge was closed on Feb. 19,
2012, it affected people traveling three ways. Lightrail trains were prohibited
from crossing under the bridge until Friday, and passengers were shuttled
through that area via bus. Vehicles were rerouted from Hiawatha Ave. onto Cedar
for a week. And bicyclists and pedestrians were no longer able to take the
bridge and keep out of traffic; instead, they all had to cross at the street
level.
Until Minnesota’s only cable suspension bridge is reopened,
those bicyclists and pedestrians will continue to dodge vehicles at the 28th
St. and Hiawatha Ave. stoplights.
At this point, no one knows when the Sabo Bridge will be
reopening. It is, however, stabilized now, pointed out Minneapolis Public Works
deputy director Heidi Hamilton.
“Before we design a fix, we want to know what went wrong,”
stated Hamilton.
Until that happens, the cost of repairing the bridge is also
unknown.
The city is not releasing any opinions on what may have
caused the cracks because no one knows what went wrong and won’t until all the
facts come in, said Hamilton. “There’s not a lot of value in speculating,” she
added.
The bridge had most recently been examined in October. City
inspectors gave the cable anchors the highest rating for soundness.
WHAT
HAPPENED TO THE BRIDGE?
At 10:06 p.m. Feb. 19, a citizen reported finding a pair of
cables lying on the Sabo Bridge deck. City workers responded, and discovered
that a partly rusted diaphragm plate had fallen 100 feet from the mast, and
released the topmost cable, number nine. A bridge inspector arrived at 2 a.m.
to examine the mast, and discovered a second crack in diaphragm plate eight.
Crews detoured vehicle traffic away from the site. The problematic effort to
shore up the eastern end of the bridge began. These supports will remain in
place until the bridge is fixed. One lane of northbound Hiawatha is closed to
accommodate these supports.
The main focus the first week was making sure the bridge was
stabilized and opening Hiawatha Ave. back up to traffic. Now the focus has
shifted to discovering what went wrong.
Minneapolis and Hennepin County have awarded Wiss, Janney,
Elstner Associates Inc. of Illinois a $100,000 no-bid contract to investigate
the cause of anchor plate fractures; the two entities will split the bill. A
determination could take four to eight weeks. Wiss, Janney, Elstner Associates
also received a $2 million, no-bid contract to investigate the cause of the
Interstate 35W bridge collapse in 2007.
Representatives of Wiss, Janney and Elstner were on the scene
by Wednesday, Feb. 22; they shipped the fallen plate to to Lehigh University in
Pennsylvania for forensic analysis.
According to Hamilton, the next day, workers removed tension
from diaphragm plate eight, which was also cracked. The number eight cable was
detached by engineers on Friday.
Wiss, Janney and Elstner began magnetic particle testing to
examine the rest of the bridge’s 18 steel anchors for cracks. A minor defect
was discovered and fixed on plate seven, and cracking found on plate five. A
temporary redundancy fix was completed the second week of February.
At the same time, the broken edge of plate number nine was
removed. “There is a lot of interest in looking at that,” Hamilton pointed out.
This piece will also be shipped to Lehigh University for analysis, and will be
used to determine why the plate failed.
Some residents have speculated that too much weight on the
bridge the day before may have contributed to the plates breaking. Gabriel
Hoffman, the Seward representative on the Midtown Greenway Coalition Board,
noted, “The situation people seem to be concerned about was the Friday night
before the cables snapped, when there was (apparently) a police car, an
ambulance, and a fire truck up on the bridge. Now, it is designed to carry that
load, so my understanding is that if there wasn’t some underlying problem with
the cable supports, it shouldn’t have been a problem. If there is a
problem with the supports, that load may have been the proverbial straw for the
camel, but not being an engineer, I would not care to offer an opinion on the
matter.”
“The bridge was designed to carry service vehicles,” Hamilton
pointed out. The bridge needs to be plowed, and emergency vehicles are able to
respond to calls on the bridge.
The city did a good job with the bridge closure, according to
Eric Hart, a Cooper resident who doesn’t own a car, but instead bikes wherever
he needs to go. “I heard about it fairly quickly and the city was very
transparent about what went wrong and what they needed to do to make it safe
for the LRT to run and the car traffic to be able to go under it.”
IS
THE CROSSING AT 28TH AVE. SAFE?
Until the bridge is back in service, bicyclists and
pedestrians will continue to cross at the street level.
As the weather warms up and more pleasure bikers join the
commuters, Midtown Greenway Coalition Executive Director and Longfellow
resident Soren Jensen anticipates that there will be crowding at the 28th St.
lights. Already during these warm spring days there have been long lines of
bicyclists waiting to cross. “It could be even more dangerous as bikers at the
end struggle to get across,” said Jensen.
“As we get into the summer, and the cyclists on the Midtown
Greenway includes more recreational cyclists (as opposed to people doing
serious training or commuters), it will be more of an inconvenience, since they
tend to feel less comfortable crossing at Hiawatha,” observed Hoffman, who
travels on the Greenway every day.
There are several issues with the crossing at 28th and
Hiawatha, according to local bikers.
“Drivers tend to be more aggressive on highways and not
respect pedestrian right-of-way at crosswalks. They’ll inch forward into the
crosswalk,” observed Longfellow resident Mike Jones, who bikes between three to
30 miles each day.
Hart noted, “The lane merging onto Hiawatha on the east side
(coming from Lake Street) is probably the most dangerous part of intersection
since it is unclear if the cars will stop and they are coming fast most of the
time,” Hart said. “The right turn lane off of 28th to southbound Hiawatha is
also problematic since cars don’t always look for pedestrians or bicycles
before they turn right.”
Five years ago before the Sabo Bridge was constructed
everyone used the street, but since then bicycle use has greatly increased in
the Minneapolis, Jensen noted. Over 4,000 people use the Greenway each day.
Minneapolis is currently second highest in the nation in the number of people
commuting to work via bicycle, at 4% of the population; Portland has 6%. And as
gas prices increase, Jensen believes more people will ditch their cars for
bikes.
Most riders view the Sabo bridge as a safer and faster way to
get across Hiawatha, according to Jensen.
“The more we can get people out of traffic, the more they
want to bike,” Jensen observed. “People won’t bike unless it is safe.”
He added, “The bridge is part of a network that makes people
feel safe. It’s a good investment.” Jensen pointed out that creating bike
lanes, fashioning curb bump-outs and creating trails like the Greenway is much
cheaper than building roads.
“The Greenway makes getting across south Minneapolis a
breeze, and I think the fact that its free of cars and intersections, have
encouraged a whole new group of bicyclists to try commuting and getting around
by bicycle for the first time and get ‘hooked,’” observed Hart. “I’ve been
biking in the city for 20 years and it is much more pleasant to go across south
Minneapolis on the Greenway than on 31st or 32nd Streets.”
The city’s traffic division is monitoring the situation at
28th and Hiawatha, according to Hamilton. Changes have been made to the signal
timing, but there are no plans to make other changes at the intersection. “Our
hope is that this is not a long-term thing. We don’t want to put money into
something that is for a short duration,” Hamilton explained.
“We are interested in getting the bridge back in use as soon
as possible,” Hamilton said. “We recognize it is a really important crossing
for bikers.”
Will people trust
bridge when it reopens?
by Tesha M. Christensen
Will people trust the Sabo Bridge when it is reopened?
Longfellow resident Kevin Baumgartner isn’t sure they will.
“Its safety record, and the confidence and comfort that goes with it, has been
shattered. People may possibly never again have as high of a confidence level
with that bridge, and that, in itself, is unfortunate and concerning,”
Baumgartner stated.
People he knows in other states have a lowered respect for
Minnesota due to the collapse of the 35W bridge in 2007 and the issue
associated with the Sabo Bridge now.
“The question I get most is ‘What is wrong with you guys and
your bridges?!’” Baumgartner remarked.
He added, “Also, within in 24 hours of the Sabo bridge
closure, the Washington Avenue bridge had Central Corridor construction debris
(the size of large bricks) fall onto West River Parkway below it. So, three bridges, all within
approximantly one mile radius of each other, have had safety problems that
causes the closures of roads. So, a poor public perception of bridges in the
state/city by locals and others is natural.”
On the other hand, Longfellow resident Katherine Debertin
isn’t any more concerned about crossing bridges now than she was before. “I
kind of think of bridges the same way I do about flying - I learned to breathe
through crossings and I learned to breathe through take-offs and landings
whenever I’m flying,” Debertin stated.
Just as there are investigations into airplane crashes, they
are into bridge issues. “I hope that
it translates into better inspection or construction or design or
to prevent future incidents,” remarked Debertin.
Howe resident Eli Effinger-Weintraub also hopes that the
failure in the Sabo bridge is another wake-up call to examine infrastructure
inspection and maintenance procedures and schedules.
Eric Hart, Longfellow’s former representative on the Midtown
Greenway Coalition Board, doesn’t see a connection between the I35 bridge
collapse and the closure of the Sabo Bridge. “This bridge was in no danger of
falling down and nobody was hurt,” he pointed out.
Hart added, “I think the Sabo bridge is unique enough that it
won’t effect people’s confidences in other bridges. There are dozens of standard concrete bridges in the city
and there haven’t been dramatic problems with them. The Sabo bridge is unique
and the first in the state, so, if anything, people will be critical that they
tried to experiment with something that was never tried in Minnesota, etc. (or shouldn’t have spent so much to
make it look flashy).”
Avid bicyclist and Longfellow resident Mike Jones agrees with
Hart that the Sabo Bridge damage is different than what occurred with the 35W
bridge because it wasn’t a catastrophic failure. He does however see how people
would make the comparison “since the same contractor was hired for both
bridges.” The Illinois-based engineering firm Wiss, Janney, Elstner Associates,
Inc. investigated the collapse of the 35W bridge and has been hired to
determine what went wrong with the Sabo Bridge.
“As people are already using the bridge by going around the
barricades, I think people will still use the bridge,” Jones said. “I do think
that some people will realize crossing at the light at 28th and Hiawatha is
fairly quick and a way to bypass the large grade change in the bridge and will
thus not use the bridge.”
DeWayne Townsend, co-chair of the Longfellow Community
Council Environment and Transportation Committee has not changed his opinion on
the safety of bridges in the area. “Two bridges among the thousands does not
indicate a trend,” Townsend said. “I still trust bridges.”
ABOUT
THE BRIDGE
The Sabo Bridge was designed by engineering consulting-firm
URS. It opened in November 2007, two months after the 35W bridge over the
Mississippi collapsed. The bridge has a total length of 2,200 feet with the
main span over Hiawatha at 220 feet. While Hennepin County oversaw construction
of the bridge, it transferred ownership to the city of Minneapolis in 2008.
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