Will Cimarron-Conejos bridge hold?
City engineer says yes, Gallagher, Clark unsure; issue will be key when Bijou bridge replaced
With 2006 looking like the year the Bijou Street bridge will be closed for replacement as part of the I-25 widening project,
current plans call for Cimarron Street to take up much of the traffic slack from the Interstate and the Westside.
City Engineer Gary Haynes says there is nothing to worry about. However, two Westside political leaders - City Council member Tom Gallagher and District 3 County Commissioner-elect Sallie Clark - have expressed doubts largely because, even after recently completed repairs, one of the street's two bridges east of I-25 is below a minimum structural rating set by the state.
That bridge, which the state built over Conejos Street and the railroad tracks as part of the original I-25 project in 1958, is the more easterly of the two bridges. The other is a lower span over Monument Creek. Some land is between the two, Haynes noted, although this is seamless to motorists.
The city spent about $700,000 over the past three years to improve the Cimarron-Conejos bridge. The pro-ject started as an emergency in 2002 after an inspection found structural weaknesses, particularly in one column (known as “Pier 2”). At different times over the past three years, traffic was reduced to one lane eastbound while workers shored up Pier 2 and reinforced other columns where rusting rebar had decayed the concrete from within.
“It was scary at first, but once we got the traffic off there, we were able to get in and fix it,” said Haynes, who has been city engineer for 21 years. The main problems resulted from the bridge's now-defunct design style, which allowed water to seep down from the bridge deck and attack old rebar that lacked protective coating, he said.
With the completion of the work this month, Haynes said the bridge is good for another 10 years. Even adding 3,000 cars a day to its present total of 19,000 - an estimate of what would happen if Bijou's I-25 span closes from January to November of 2006 so a new one can be built there - will not be a problem, Haynes said.
James Flohr, a lead Colorado Department of Transportation (CDOT) engineer in the I-25 widening plans, has accepted Haynes' analysis as correct, he told attendees at a meeting of the Organization of Westside Neighbors (OWN) Nov. 4.
CDOT plans to keep I-25's Cimarron interchange open while the new Bijou bridge goes in. Much of the added traffic on the Cimarron-Conejos bridge would come from northbound I-25 vehicles that otherwise would get off at the Bijou exit. Southbound vehicles would have a different scenario. Under tentative plans - which still could change depending on ideas a contractor might come up with - southbound vehicles could exit west of the Bijou bridge, then be funneled along a temporary connection to Colorado Avenue via Spruce Street, Flohr said.
Gallagher told the Westside Pioneer he is displeased that even after re-pairs the Conejos-Cimarron bridge still only scores 49 on the state's 100-point scale. Typically, a bridge that scores below 50 is planned for replacement, City Trans-portation Planning Manager Craig Blewitt has previously told the Westside Pioneer.
Haynes said the score for the Cimarron-Conejos bridge is misleading, by representing factors that do not actually relate to structural integrity, such as its age, antiquated handrails, road width and traffic volumes. By contrast, when the problems were found in 2002, the bridge only scored a 23, he noted.
“When I heard that rebar had popped and what it was scoring, I couldn't believe we were going to patch it,” Gallagher said. “It's a wonder it's still standing.”
In less than 10 years, the bridge is scheduled for replacement. The estimated $4.8 million cost is to be covered by the Rural Transit Authority (RTA) 1-cent sales tax, which was approved by county voters this month. The RTA has a 10-year time frame to do 75 projects. Of these, 47 are top priority, and the bridge is among them.
Clark shares Gallagher's worry. At the OWN meeting, she questioned CDOT's wisdom in increasing the load on a bridge that is “being held up with braces.” She elaborated this week that she would like to see traffic studies to help limit the number of cars meandering through neighborhoods seeking faster routes during the Bijou repair. Another wish of hers is for a firmer bridge- replacement schedule to prevent the unfortunate chance that - through lack of foresight or the Cimarron bridge failing - both it and the Bijou bridges would be out at the same time.
Council member Jerry Heimlicher, whose district includes the bridge, said he accepts Haynes' report on its structural integrity “because that's what the guy gets paid for.”
Describing the work, Haynes said, “We went in and removed the damaged concrete and replaced it with solid material. We removed the rust from the reinforcing steel and repainted the steel with galvanized paint that prevents rust, then installed steel bands around those areas with tightening screws… It is structurally sound.”
Another important element is that the bridge will get annual inspections in the years ahead, instead of every other year, as in the past. As a result, “if we detect problems, we can be on it quickly,” Haynes said.
Westside Pioneer Article