Austin Avenue bridges facing fight against the clock

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Since May vehicles weighing more than 48,000 pounds have been prohibited from driving across both Austin Avenue bridges spanning the San Gabriel River just north of downtown.

The load-bearing limits were put in place by the Texas Department of Transportation after structural deficiencies were found during inspection of the bridges in December. Problems included asphalt cracking, rusting and crumbling portions of concrete, Georgetown Transportation Services Director Ed Polasek said.

The limit restricts travel for large vehicles including the Georgetown Fire Departments ladder truck as well as fuel and garbage trucks, he said.

We want to make sure we have a reliable road by which we can respond to … emergencies, GFD Fire Chief John Sullivan said, adding that the fire department has been able to make adjustments to maintain response times. Long-term [the bridge limit]would have an impact, but short-term its not an impact.

Sullivan said according to international fire codes, the roadway should be constructed to accommodate 75,000-pound vehicles.

Although the structures have been deemed safe for traffic and are not in danger of failing, Polasek said they need to be replacedif not now, then soon.

Even if we do replace the deck or do minor repairs to the bridges, eventually you are going to have to replace the entire thing, he said. Its a matter of how do you want to pull the Band-Aid off? Do you want to do it all at once and get it over with, or do you want to do it in five, 10 or 15 years?

On July 8, Georgetown City Council approved a contract with Aguirre & Fields LP to complete a final financial analysis and recommendations for the bridges.

Right now everything is pointing to total replacement of the structures, Polasek said.

However, the council could decide to move forward with minor repairs or a total roadway replacement, which could extend the lifespan of the 75-year-old bridges another five to 20 years and could possibly eliminate the weight limits, he said.

In my view those bridges need to be returned to full capacity as soon as possible, City Councilman Keith Brainard said. The bridges can be restored to full capacity either by temporary fixes or total replacement, but eventually well need to replace them.

Since the cost of replacing the bridges is likely to rise, the most prudent choice appears … replace them sooner rather than later.

Polasek said the only option to get rid of the weight limit would be total replacement of both bridge structures.

We have to find a way to stop [the bridges]from degrading or bring [them]back up to a sufficiency rating that allows those [heavier]vehicles to go across the bridge, he said. The other options would mean either the load rating in the next evaluation gets even lower or remains the same. If it gets lowered even more and starts affecting more vehicles, then it becomes an issue for the city.

History

The bridges, which were built in 1939, have had minor repairs and maintenance performed on them throughout their history; however, there have been no major construction projects or maintenance work done since they were opened, Polasek said.

In 2001, Austin Avenue, including the two bridges, was a part of the TxDOT system and was maintained by the state. At that time the state proposed expanding the road to five lanes from Williams Drive through downtown and replacing the bridges, Polasek said. The proposal was rejected by the city, and in 2006 the city of Georgetown took over responsibility of the roadway.

Were in that position now where we took it over, and now we have to manage the repairs, Polasek said.

Because the bridges are no longer a part of Texas roadway system, they would have to qualify for funding from TxDOTs off-system bridge replacement program, he said.

Now [the bridges are]under our control, and we have to have a certain bridge rating in order to be eligible for state funding, Polasek said.

The bridges would have to be rated below a score of 50 on a 100-point scale, he said. As of their December inspection, the bridges were rated in the low 60s.

Were still above a 50 because our substructure is still good enough, and it can be repaired, Polasek said. So there is some potential for repair money [for]the existing structure, but it doesnt solve our long-term issue and it possibly doesnt remove the [weight limit]on the bridges.

However, Brainard believes the state should help foot some of the bill.

Because the bridges were within the purview of TxDOT for most of their existence, until just a few years ago, it seems appropriate that TxDOT would help fund a portion of their replacement, he said.

Polasek said the city is still in discussions with TxDOT for possible funding options.

Construction options

Polasek said the initial bridge assessment completed by Aguirre & Fields offered four options ranging from doing nothing to total replacement.

The estimated cost to replace both structures is $6.1 million, which does not include bridge projects proposed in the Downtown Master Plan, which was adopted by City Council in March, Polasek said.

To implement the Downtown Master Plan recommendations, we are going to have to replace both the superstructure and the substructure [of the bridges], he said, adding that any substantial maintenance or upgrades would automatically trigger the need to update the structures to current safety standards.

Anything we do with the bridge, we have to bring the bridge up to current safety and [Americans with Disabilities Act] standards. Replacing the deck would cause us to have to do that, too, Polasek said.

The city applied for funding through the Capital Area Metropolitan Planning Organizations Surface Transportation ProgramMetropolitan Mobility Program on July 18.

We [will]work on [the city staffs]side to find a solution to funding for the ultimate solution, which is replacement, Polasek said.

He said a decision by CAMPO could be announced in two months, and the final cost analysis is expected to be presented to City Council in October.

Polasek said the project could also be included in the citys road bond proposal, which could go to voters in May 2015.

If total reconstruction was approved, Polasek said the project would most likely be completed in phases, two lanes at a time.

That was the biggest concern when this all startedwhat would happen if the bridges were shut down for a significant period of time? We are probably going to pay extra in construction costsit would be quicker and more efficient to just tear it down and rebuild itbut you cant live for six to eight months with that bridge being shut down [to]downtown merchants, traffic and the impacts overall, he said. So [work on]two lanes [at a time]is probably the best solution we can do right now.

Bridge options

An initial cost analysis completed by consultants Aguirre & Fields LP presented four options for dealing with the Austin Avenue bridges spanning the San Gabriel River just north of downtown. Cost estimates are based on current construction costs, Georgetown Transportation Services Director Ed Polasek said.

Option 1Do nothing

Weight limits for vehicles remain or allowable weights decrease

Bridge life span: Five years

Cost: $20,000 in design and repair costs; $6.1 million to replace bridges in five years

Option 2Short-term repairs

Repairs beams and girders to restrict rust and deterioration; weight limits remain

Bridge life span: 10 years

Cost: $640,000 for initial repairs; $60,000 in design and repair costs in the next 10 years; $6.1 million to replace bridges in 10 years

Option 3Replace roadway

Remove roadway deck and replace; would require upgrades to current safety standards; weight limits may or may not be eliminated

Bridge life span: May add 1520 years of service life

Cost: $2.6 million in initial construction; $60,000 in repair costs in next 20 years; $6.1 million to replace bridges in 20 years

Option 4Replace bridges

Remove existing structures and replace with new bridges that could support additional pedestrian amenities including expanded sidewalks, a gazebo and pathway to the river; construction could be phased to allow two lanes of the existing bridges to remain open.

Bridge life span: 75 years

Cost: $6.1 million

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