Grand Ave. Bridge EA - Enthusiastic Support for the New Pedestrian Bridge Type
GLENWOOD SPRINGS –At an August 1, 2013, workshop with Glenwood Springs City Council, a pedestrian bridge that focused on historic elements consistent with downtown Glenwood Springs was unanimously favored. This was consistent with what the project team had heard from public comments on pedestrian bridge types and features at public meetings, Strawberry Days exhibits and Downtown Market events.
A new pedestrian bridge was not originally part of the Grand Avenue Bridge project. The concept was introduced as part of the overall solution last fall when the project team began looking at how to demolish and construct the highway bridge. There are numerous utilities under the highway bridge that will have to be relocated before the existing bridge can be removed and replaced. The most efficient way to relocate these utilities was to place them on a new pedestrian bridge. The new pedestrian bridge also facilitates accelerated bridge construction techniques, important on this project to minimize impacts.
As this concept was considered in the evaluation process, it became apparent that a new pedestrian bridge would address almost all of the project criteria, including multimodal connectivity; safety and consistency with regional planning. As well, it has the potential to offer better harmony within the community, have reduced overall construction costs, minimize impacts to private property, and reduce overall impacts.
The benefits and issues to consider in replacing the pedestrian bridge were presented at a combined Project Leadership Team/Project Working Group meeting back in October 2012. In November, the project team asked the Stakeholder Working Group to comment on the advantages and disadvantages of a new pedestrian bridge and what the bridge might look like. After initial input from this group, the project team developed a list of 14 potential bridge types that could be considered.
Attendees at the January 9, 2013, Public Open House commented on the 14 bridge type options and how some of them would look when paired with different Grand Avenue Bridge options. In addition to improving on the functionality of the existing bridge, public input suggested that the new pedestrian bridge would need to complement the highway bridge, accommodate both pedestrians and bicycles, and incorporate the aesthetics and historic details that fit the historic context of Glenwood Springs.
The project team considered the public and stakeholder comments at a bridge design workshop held in February. The team’s bridge architect, engineers, and environmental experts discussed the merits and disadvantages of a wide range of bridge types. After two days of discussion, the project team narrowed the 14 options to three options to be considered in more detail. These options were: 1) a single-tower, cable-stayed symmetric span bridge (two equal spans); 2) a single-tower, cable-stayed asymmetric-span bridge (spans of different lengths); and 3) an arch bridge that spans from the south bank to north of I-70.
During the discussions and subsequent evaluations, the project team evaluated the bridge types using several criteria: environmental impacts, site constraints/opportunities, aesthetics, constructability/phasing, schedule, maintenance, cost, span, and other impacts.
Renderings and models were presented to the Glenwood Springs City Council, other stakeholders, and the public while conceptual design details were being developed. There was no overwhelming support for any one of the options. After feedback was received on May 30 from the Stakeholder Working Group and the City Council voiced concerns that the current options did not reflect the character of the community, the project team reset their direction and developed three bridge types to present to the City Council on August 1.
“All of the bridge types we have considered would meet the purpose and need of the project, and would work from an engineering perspective,” CDOT Region 3 Central Program Engineer Joe Elsen said. “The public process helped us come up with the best solution for the community. We listened, redesigned, and now have what we believe to be a winning option that will be cost-effective to design and build.”
The current bridge type is what is called a five-span, variable-depth girder bridge. The 16-foot-wide bridge would be supported by girders under the deck rather than cables and towers above the deck, features found to block the views of the mountains and the river. The bridge would also clear span the Colorado River and incorporate several shorter towers with architectural elements consistent with the historic character of Glenwood Springs. It would accommodate both pedestrians and bicyclists, with the potential for overlooks and other amenities.
Gaining the endorsement of the City Council at their August 1st meeting and input from the individuals who have viewed the renderings at theTuesday Downtown Markets means that the project team can start developing additional design details.
“Arriving at one solution from where we started was the result of the community’s vision for a context-sensitive design, an open and public process, and a talented group of bridge architects and engineers who were open to considering the range of options until we got it right,” Elsen said.
The public can see conceptual renderings in the lobby of the Glenwood Springs City Hall, 101 West 8th Street. The model will also be available every other week at the Downtown Market in Centennial Park Tuesdays from 4:00 to 8:00 p.m.
Those wanting to receive project updates can sign up via CDOT’s free message system by going to www.coloradodot.info and clicking on green cell phone in the upper right hand side of the page. After signing in, scroll down to “Projects” and choose “SH 82 Aspen to Glenwood.”
The project is funded through the Colorado Bridge Enterprise, a government-owned business entity within CDOT. The Colorado General assembly created the statewide Bridge Enterprise via Senate Bill 09-108, also known as FASTER (Funding Advancements for Surface Treatment and Economic Recovery).The purpose of the Bridge Enterprise is to complete designated bridge projects that involve the financing, repair, reconstruction and replacement of bridges designated as structurally deficient or functionally obsolete, and rated “poor” by CDOT.