ACEC

Jefferson Street Pedestrian Bridge

Firm: IMEG Corp. and Larson & Darby


Other Consultants:


Owner: Rockford Park District


Description: ENTRANT’S CONTRIBUTION TO THE PROJECT Original or innovative application of new or existing techniques: Originally constructed in 1988, the Jefferson Street Pedestrian Bridge provided a link across the Rock River from the nearby Rockford Public Library and Beattie Park but was closed in 2015 due to deterioration caused by age and corrosion from salt water. To correct the damage, the structure was completely removed and replaced with a new, prefabricated steel truss pedestrian bridge with composite weather-resistant decking painted with corrosion-resistant materials. Working in collaboration with the architect, overhead stormwater diversion canopy structures were designed and installed to divert rain from the roadway bridge above. Pressure-treated, southern pine deck boards that are resistant to warping were utilized on the pedestrian bridge and allow it to be used year-round. These efforts will reduce the amount of maintenance the pedestrian bridge will require in the future and increase the structure’s overall lifespan to essentially match that of the roadway above it. Future value to the engineering profession and perception by the public: The Jefferson Street Pedestrian Bridge serves an important function in the community as a safe route for pedestrians and bicyclists to cross the Rock River without traffic hazards. To ensure the new bridge would be visually appealing and have a long lifespan, IMEG worked with the other team members and the Rockford Park District throughout the development of the project to incorporate aesthetically pleasing design elements while also protecting the structure from saltwater runoff from the roadway above. This included the use of a silver powder-coat finish that is weather resistant and matches the similar style and colors of other pedestrian bridges located along the Rock River. Treating the boards on the decking and applying corrosion-resistant coating to the structure will eliminate premature deterioration and allow the pedestrian bridge to remain in better condition visually and structurally for a long period of time. This adds aesthetic value to an already iconic structure in the Rockford community and will reduce maintenance and the need for renovation in the future. Social, economic, and sustainable design considerations: Frequently featured in imagery depicting Rockford’s downtown — from photographs and postcards to television live-cams — the main purpose of the Jefferson Street Pedestrian Bridge renovation project was to accommodate the current and future needs of pedestrians, bicyclists, and the handicapped. With this in mind, the needs of each demographic were carefully considered. The width of the bridge structure and ramps is 10 feet rail-to-rail and the longitudinal grades less than 5 percent, making it compliant with the Americans with Disabilities Act. Several different surveys, analyses, and tests were conducted prior to construction to collect data on the project, determine the scope of work to be done, understand and plan for safety issues. The project’s effect on the environment also was considered, and measures were taken, to avoid contamination or pollution of the Rock River Complexity: Though the existing deteriorated bridge structure was completely removed and replaced, the existing ramps on either end of the bridge were retained and severely deteriorated structural members repaired or replaced. The ramp structures were then painted to match surrounding architecture with the same silver powder-coat used on the bridge structure. The demolition and construction stages of the project were completed from the river surface and east bank, which required elaborate erection plans, including a temporary construction access road. Approvals were secured from the IDNR/OWR and the U.S. Coast Guard to allow use of barges. During the demolition phase, gantry cranes on the barges supported, released, and safely lowered the spans of the existing structure onto the barges. As opposed to using equipment that would have been physically attached to the roadway above, this removal option was faster and allowed the roadway to remain fully operational during the entire construction process. The concurrent demolition of the nearby Rockford Public Library also posed additional safety and traffic concerns early in the project. However, through construction staging and planning, traffic was successfully rerouted to allow continued access to the roadway, bridge, and other buildings in the area while avoiding both the library and pedestrian bridge construction sites. This effectively resolved safety and travel concerns. Exceeding the owner needs: The project resulted in a beautiful renovation of one of the most recognizable and utilized structures in Rockford. Considered an outstanding success by the Rockford Park District, the renovations achieved the goals and outcomes set forth by the city and the designers, all of whom worked in collaboration to create a safe, cost-effective, and environmentally conscious route for pedestrians. “Our expectations were very high for this project, and we are extremely pleased with the way the project was both designed and constructed by the IMEG Corp./Larson & Darby team,” said Jay Sandine, Rockford Park District Executive Director. “Now that the project is completed, it’s a real pleasure to watch thousands of pedestrians enjoy this beautiful amenity.”





Rockford Park District