The oft-traveled 600 North viaduct has been the object of scorn and derision for years.
Soon, that may change.Planners, engineers and architects plan to raze the 1,625-foot, two-ramp structure and replace it with a better, wider bridge. According to David Christensen, chief structural engineer for the Utah Department of Transportation, construction could begin as early as next summer.
The 29-year-old bridge has been crumbling for the past 10 years or so. And inspection reports at the state and federal level have continually branded it "deficient."
Corrosion and cracks, caused by winter snow-removal procedures, are destroying the bridge. Crumbling concrete, weakened reinforcements and exposed wooden and steel beams, in turn, have reduced its original load capacity.
"My understanding is it's one of the worst bridges in the state," said Doug Atkins, project manager for the I-15 corridor. "There is justification for it to be replaced."
More than 28,000 motorists use the viaduct each day. It provides a main link from the Rose Park-West Bountiful area to downtown Salt Lake City. Nearly 11 percent of the daily load is commercial truck traffic.
The problems that plague 600 North are found at other area bridges, too. Of Utah's 1,710 bridges, 166 carry the "deficient" rating. Many of them are "high-volume" bridges, those that handle the most traffic. The low-volume bridges, which are mostly in residential areas, have had weight limits imposed on them.
Christensen said defects in structural capacity or ability to handle waterway flow are the most common reasons for labeling a bridge deficient.
According to Christensen, some of the state's worst thoroughfares are Route 201 westbound to I-80, SR 202 at the Garfield cutoff, 500 and 600 South along I-15, I-80 near Highland Drive, 2300 East over I-80.
Though a 25-ton or 50,000-pound weight limit has already been imposed on SR 201 and SR 202, the legal limit for 600 North remains 40 tons or 80,000 pounds, though lowering the limit has been discussed.
"Right now we have no plan to impose weight limits. The bridge is deteriorating to the point where we need to replace it," Christensen said. "We've done a tremendous amount of work on the bridge, and considerable effort has gone into maintaining it. It's a very expensive bridge."
For the past two or three years, UDOT has monitored the bridge every six months or so, more frequently than the one inspection every two years required by federal law, Christensen said.
"Right now the bridge is in bad condition, but we still feel it will serve motorists without hazard," Christensen said.
According to a recent USA Today story, Utah has the ninth most hazardous bridges in the nation. The report says the state, with a 45 percent bridge deficiency rate, has more substandard bridges than it did in 1982.
But Christensen refutes the claim. And 1988 Deseret News reports show the state has instead improved its record.
In 1988, 332 of 2,463 or about 13 percent of Utah bridges were considered deficient. Today, Christensen reports 166 of 1,710 bridges are deficient, a 9.7 percent rate.
"I'm not sure how they sampled their data. We certainly don't have that high a number (of deficient bridges)," Christensen said. "If they looked at all the (state's) bridges, I would have to disagree. If they looked at subgroups of high-volume bridges, then it's a possibility."
The Utah Legislature has appropriated nearly $6 million dollars to the state highway system for fiscal year 1995, which began in July. Local governments will receive $1.3 million to repair or replace deteriorating thoroughfares, said Dave Miles, UDOT's program development engineer.
The 600 North project, which is being studied for its environmental impact on the area and is proposed as a three-lane bridge in each direction, is estimated to cost $8 million dollars, said Craig Peterson of Versar Architects and Consultants, the firm assigned the project.
"The question is not should (the bridge) be replaced, but how should it be replaced and with what. We are proposing a state-of-the-art bridge, using the latest design in corrosion protection," Peterson said. "We're not sure if it will be steel or concrete, that depends on the cost, durability, life-span and aesthetic value. Our goal is to have the environmental impact report completed about a year from now."