There are no easy solutions when it comes to the future of the 16th Street viaduct, but members of the Hastings City Council are hesitant to raise taxes to replace the 84-year-old structure.
That was the outcome of the council’s work session Monday night, which was the first council meeting to address the old overpass, since it closed May 31. Discussion of the 16th Street viaduct was the only item on the work session agenda.
Acting on assessments by a representative from the Nebraska Department of Transportation’s bridge inspection program in November 2018 as part of a regular evaluation, and then a follow-up inspection by engineering firm Olsson on April 3, city officials determined to temporarily close the old overpass on May 31.
Engineers Tyler Cramer and Emilie Hudon, bridge experts for Olsson, provided a presentation during the work session about the 16th Street viaduct and possible options for repair and replacement.
The city received Olsson’s bridge assessment report on May 10.
The Olsson assessment agreed with the state inspection that the bridge substructure is in serious condition due to the spalling of the concrete and the rusting of the reinforcement under and near abutment 1 bearings of girders A and E and pier 6 and eight bearings of girder A.
Based on condition code trends of the last 12 years and the differences seen between the November 2018 inspection photos and the Olsson assessment, Olsson estimates the substructure will fall into critical condition in six to nine months, and at that point bridge closure would be mandatory.
Immediate action is required to repair the substructure concrete around the bearings at abutment 1 and at piers 6 and 8. The expected service life of the bridge with these repairs is only two to three years, after which extensive repair, replacement, or closure will be required. The probable cost of these immediate repairs is $150,000.
“The substructure recently declined to a bridge condition code of 3, which is serious in bridge condition terminology,” Cramer said. “Once it goes to a 2, which is critical, the bridge must be closed without repair or being replaced.”
He said the bridge has seen significant deterioration, even since 2017.
According to Olsson’s bridge assessment report, the substructure was a 5 — fair — in 2007, dropping to a 4 — poor — in 2013, which was the year fencing was added around the piers, and dropped to a 3 — serious — in 2018.
The deck and superstructure remain in better condition; an 8 — very good — in 2007 and have dropped to a 6 — satisfactory.
The bridge was constructed in 1935. Its deck was replaced in 1985.
When the viaduct was constructed it was the north entrance to Hastings on U.S. Highway 281.
Since that time, Highway 281 was rerouted — in the early 1980s — a few blocks to the west, and the Elm Avenue overpass was constructed in the early 1990s.
Rehabilitation is estimated to cost $2.275 million with a service life of 30 years.
Full replacement is estimated to cost $5.7 million with a service life of 75 years.
Permanent closure, which would reroute traffic to one of the nearest open railroad crossings, is estimated to cost $500,000. Because the bridge is an alternate route, removing it would lead to higher traffic on U.S. Highway 281.
“There are no good options with this viaduct,” Mayor Corey Stutte said.
Discussion on Monday focused primarily on full replacement.
No decisions were made and council members talked about having further meetings to discuss options and creating a fact sheet to address questions.
Stutte said the old overpass will be closed for at least a year.
“The timeline does not look good for repair, before the freeze-thaw this year,” he said. “So to be clear with the public, the earliest, by the time we get the engineering done on something and get the bids let, find a contractor and deal with the railroad, it’ll be a year from now, at the earliest.”
The city is currently doing traffic counts on the Burlington Avenue overpass.
City engineer Dave Wacker said so far, traffic counts have shown an average of about 22,000 vehicles on the Burlington Avenue overpass — 11,000 each direction.
Traffic counts on the Elm Avenue overpass averaged more than 2,400 vehicles per day in the days leading up to the 16th Street viaduct closure.
A traffic study conducted by the city of Hastings’ engineering department on the 16th Street viaduct during the afternoon and evening of May 16 as well as May 17 and 18, showed an average daily traffic count of 3,931 including 154 trucks.
Fire chief Brad Starling said fire engines do take the 16th Street viaduct, to avoid rush hour traffic on U.S. Highway 281. The 16th Street viaduct also provides alternative access if 281 is shut down such as for a traffic accident.
“With it not being there, does it hurt our response time to that area? Particularly the medical park? No it doesn’t,” he said. “It certainly withdraws alternative access routes should Burlington be shut down.”
Stutte said he has received a lot of comments about the 16th Street viaduct on social media, including some asking if it would be possible to use money generated by the city’s half cent sales tax that was renewed in 2017 and earmarked for projects such as improvements to Hastings parks.
“No that was a vote of the people that was approved for that — same thing goes for quiet zones,” Stutte said.
Likewise, he said the city could not make the Union Pacific Railroad pay for a replacement overpass.
“I’ve gotten some comments saying ‘stick it on the railroad;’ that is not going to happen,” he said.
City administrator Dave Ptak said a bridge replacement would require a public vote.
“What this is ultimately going to boil down to is whether the people of Hastings are going to support a new bridge there or whether we are looking at a closure,” Stutte said. “No matter what it is not going to be open for the next year.”
The city is still receiving public comment at the email address firstname.lastname@example.org. Development services director Don Threewitt said during the meeting that 32 comments had been submitted to that email address.
Ptak presented financing options for a viaduct replacement, assuming a $6 million bond issue, that were prepared by the city’s bond counsel, Phil Lorenzen of Omaha firm D.A. Davidson.
According to those options, a 5-year amortization with an average interest rate of 2.50 % would have an estimated annual levy of 9.375 cents per $100,000 of taxable value — meaning a $100,000 house would see a $93.75 property tax increase per year for 5 years. The annual debt service would be $1.292 million.
A 10-year amortization with an average interest rate of 2.75 % would have an estimated annual levy of 5.045 cents per $100,000 of taxable value — meaning a $100,000 house would see a $50.45 property tax increase per year for 10 years. The annual debt service would be $695,000.
A 15-year amortization with an average interest rate of 3% would have an estimated annual levy of 3.648 cents per $100,000 of taxable value — meaning a $100,000 house would see a $36.48 property tax increase per year for 15 years. The annual debt service would be $502,600.
A 20-year amortization with an average interest rate of 3.3% would have an estimated annual levy of 3.009 cents per $100,000 of taxable value — meaning a $100,000 house would see a $30 property tax increase per year for 20 years. The annual debt service would be $414,600.
“That’s $414,600 that could be going to something else,” Stutte said. “That’s something the community needs to think about. Even if we were able to do this without raising the levy, you’re still taking that $414,600 for 20 years.”