Bridge Bundling

Bridge Bundling

Stretching Community Resources to Meet Community Needs

By Stephen Sostaric

Bridges. Just the word can inspire visions of soaring steel trusses or suspension cables flung from shore to shore. The biggest and most famous can inspire and have become travel destinations in their own right. But while the importance of bridges that carry major interstate highways over the rivers and harbors of the nation is obvious, rural residents know that the thousands of smaller bridges throughout their counties are every bit as important. These critical connections are vital links for farmers to bring what they produce to market. Rural bridges tie together the local road networks that help feed the world.

The state of our infrastructure has been much discussed in recent years, and bridges have figured prominently. Infrastructure projects, however, require time and money to design and complete. This is where the innovative concept of bridge bundling comes in. So what is bridge bundling?

Bridge bundling allows for the replacement, rehabilitation, or repair of two or more bridges under a single contract. This means highway departments are able to significantly reduce project costs and maximize resources. Recognizing the benefits of fixing the rural bridges that Illinois farmers use every day, the Illinois Soybean Association has been working to bring bridge bundling to Illinois.

Currently, Illinois has 2,397 bridges classified by the Federal Highway Administration (FHWA) as being in poor condition, about 9 percent of the total bridges in the state. Of this number, 29 percent are owned by the state, 15 percent by counties, 44 percent by townships, and 12 percent by municipalities.

ISA’s initial efforts began with educating stakeholders across Illinois with webinars explaining bridge bundling. These highlighted case studies with bridge contractors and other state departments of transportation that have successfully implemented bridge bundling. States represented included Kentucky, Missouri, Pennsylvania, and Ohio. Finally, this message was taken directly to highway engineers when the ISA team spoke at the Illinois County Engineers Association’s state conference. The discussions inspired by this outreach provided valuable real-world insights that played a key role in refining the project.

The project’s original goal was to support the Illinois Department of Transportation (IDOT) in developing a bridge bundling program like other states had. Since the state had the most bridges rated poor of any single entity, bringing IDOT on board would provide the most initial bang for the buck. Once IDOT began the implementation of its own bridge bundling system, the team’s focus shifted to the remaining bridges under local control.

“Over 70 percent of bridges in Illinois are under local control,” says Todd Main, ISA Director of Market Development. “These are also the entities that need the most support for projects like this due to limited resources. Once IDOT had started on their own program, we knew it was time to shift to a bigger focus.”

Having the time to compile grant applications is one of the biggest constraints for local stakeholders. To help ease this process, ISA has created an online Bridge Bundling Dashboard. Pulling data from the FHWA, the dashboard uses an interactive map of Illinois to provide the status of each county’s bridges. This data helps illustrate the need in a given county. To further facilitate this process, ISA is also currently working to create a toolkit for local entities to use as a how-to guide when creating and implementing bridge bundling programs at the local level.

One example of how this effort is finding success at the local level is Boone County in northern Illinois. They have already started one of the first local-level bridge bundling projects in the state, with a project for five bridges. Justin Krohn, Boone County Engineer, has been spearheading the effort. “We have a growing issue with rural bridges, particularly rural township bridges, and funding inadequacies. Bridge bundling is one of the tools in our toolbox to reduce expenses and get more done more efficiently,” says Krohn. As the lead entity for the project, he has been bringing together representatives of Boone and McHenry Counties as well as two different Army Corps of Engineers districts and two different IDOT districts. “It’s a lot of work to get everyone working together and on the same page.”

Krohn took the initiative after hearing about other real world examples. “After attending a FHWA work group with others who have done bridge bundling in 2021, we posted a request for qualifications for our own bundling project,” says Krohn. “We saw a lot of interest in the project, ultimately receiving 18 submissions from engineering firms.” Ultimately the firms Chastain & Associates and TranSystems were selected in early 2022 as the consultants for Phases I & II of the project, covering planning, design, and permitting of the bridges.

The five bridges in Boone County’s bundle are all located along nearly six miles of Piscasaw Creek in northeast Boone County and northwest McHenry County. Three of the bridges are in Boone County, with McHenry County coming on board the project in 2022 with another two. All of them were built in the 1950s and 1960s with timber substructures on timber pilings. As bridges deteriorate, load limits are first put in place, eventually leading to a full closure if nothing is done. Krohn’s goal is to avoid this extreme measure to preserve rural road connections that are needed to keep the county’s farmers as profitable as possible. “Detours mean more driving when bringing products to market, leading to higher expenses cutting into farmers’ profits,” he says. “Some of them could have detours of up to 10 or 20 miles because these bridges all cross the same waterway, and that’s what we want to avoid.”

Currently, two of the five bridges have load limits, with the remaining three heading that way if nothing is done. Says Krohn, “Closure is next, but we’re trying to stay in front of the curve and prevent them while also preventing load limits on the remaining three.” While they have low daily traffic counts, they are important for farmers in the area.

From the beginning, Krohn has recognized that the project plays an important role as one of the first local bundling projects. “We made it clear that we wanted to gather data throughout the process that can be used not only in future bundling projects in Boone County, but around the state,” he says. This data gathering compares the cost of a single bridge versus costs when spread across multiple bridges. The results have already been impressive.

“The first bridge absorbs the bulk of the costs associated with surveying and design, so any remaining costs are site-specific to the changing field conditions at each bridge,” says Krohn. So far, the analysis has shown an impressive 48 percent savings for each of the additional bridges. The expectation is that savings will continue into the construction phase, with the ability to duplicate methods and reuse materials such as concrete forms.

The next challenge is finding funding for the construction phase. Boone County is already submitting applications for federal grants to construct the new bridges. Krohn remains optimistic, “We are hoping to be able to move to the construction phase by 2025 or 2026.”

With the data already showing big savings, Krohn wouldn’t hesitate to do more bridge bundles in the future. “We are always looking for ways to save on time and cost, and so far this is indicating savings in both of those areas. Once IDOT has a process in place for procedures and methods when bridge bundling, I anticipate we will see even more time savings.”

“It’s a great tool for the right projects in the right location,” he says. “It’s not a tool for every project, but for the right project it offers the kind of time and cost benefits that can get you ahead of inflation and any use restrictions on the bridges.”

With organizations like the Illinois Association of County Engineers and IDOT itself watching closely, Boone County is blazing the trail for local bridge bundling in Illinois. Coupled with the work IDOT and ISA are doing to move the bridge bundling concept forward, the future for Illinois bridges is looking bright.