It has existed since 1889 and for about 100 years under another name, the Terminal Railroad Association of St. Louis (TRRA) owns 50 miles of mainline railroad tracks, a major grading yard and other peripheral yards, two Mississippi River bridges, river ports and other facilities that serve as an economic engine for the Missouri and Illinois regions .
TRRA is working to ensure that freight and passenger trains continue to run smoothly through the St. Louis.
In recognition of its support of Mississippi commerce and to meet the demands of financing and rebuilding aging bridges to meet contemporary rail needs, ENR Midwest has named TRRA as the 2024 Owner of the Year.
TRRA takes two bridges
Even before construction on the Merchants Bridge, the older of the two bridges, was completed, TRRA began work on the MacArthur Bridge, an ongoing project that has already resulted in the replacement of one truss single section for a three-span girder bridge, the demolition of the abandoned road bridges and the installation of a retaining wall.
The $222 million replacement of the Merchants Bridge, which serves five Class 1 railroads and Amtrak, is slated for completion in 2022. The original bridge dates to 1890 and was designed by George Morrison, who designed some of the first country’s large-scale steel truss bridges.
As the years passed and the Merchants Bridge and MacArthur Bridge, which opened in 1917, continued to age, TRRA was faced with a decision.
“The issue was major rehabilitation of the bridges or obsolescence. The final decision was a major rehabilitation, in fact, replacement,” says Eric Fields, TRRA Chief Engineer.
Increase in railway capacity
The replacement Merchants Bridge, which won ENR Midwest’s 2023 Highway/Bridge Best Project Award, will increase the capacity of the rail bridge to help meet the projected increase in rail tonnage demand of more than 49% and will increase economic activity by $456 million over the next 20 years, TRRA projects.
“The issue was major rehabilitation of the bridges or obsolescence. The final decision was a major rehabilitation, in fact, replacement.”
—Eric Fields, Chief Engineer, TRRA
Work on the Merchants Bridge involved the replacement of three 520-foot-long double-track truss spans and the seismic retrofitting and anchoring of the existing masonry river piers. The east and west approach structures were improved by adding ballasted decking to 940 feet of existing deck plate beam approach lights and encasing an existing 750-foot steel trestle in lightweight concrete fill with stabilized earth walls mechanically
Fitting a trestle to improve its clearances and load capacity in an area known for seismic volatility, Fields says, while keeping trains running, is a model for other Mississippi River bridges with similar challenges.
“Some of the techniques used on the Merchants’ Bridge will be transferred to other bridges,” he says. “If you fit a trestle and put in some foundation elements to strengthen it, you can do all that work under the track so you don’t affect traffic or customers. You can get these trestles to have a good load capacity and do it in a way relatively cheap”.
The Merchants Bridge replacement was completed on time, thanks to TRRA’s coordination, says Dan Sieve, senior project manager for Walsh Construction.
“During our design and planning to replace the Merchants Bridge, TRRA enabled teamwork by inviting us to work with their engineers. [and] safety and operations personnel to come up with solutions that were feasible while we were dealing with a 130-year-old structure and a working railroad,” says Sieve. “The results of this communication process allowed us to compete on the span replacement in a 30 % less time than they had planned.”
Kevin Eisenbeis, national bridge practice leader at Burns & McDonnell, who was structural design lead on the Merchants Bridge, agrees that working with TRRA was collaborative.
“As the owner, TRRA oversaw and directed the project, but was very receptive to the ideas presented by the design team,” says Eisenbeis. “The design considered a variety of span designs, pier locations and potential construction schemes in the early design stages. The TRRA team played an integral role in arriving at the final design solution.”
Brent Wood, president and chief financial officer of the rail association, says Fields oversaw construction projects in general while an engineer was assigned to handle day-to-day operations with contractors.
“That helped the relationship with Walsh and other contractors because if they needed something, they knew where to go to act,” Wood says. “We had a lot of interruptions in their process when we needed trains to clear the bridge and vice versa, when they needed track time. We had to plan ahead. I think our role was to be a quarterback.”
Walsh and other contractors were given a track on the Merchants Bridge to work on so that the trains could continue to run, and they did much of the work under the bridge. At its peak, there were between 100 and 200 people working on the structure.
Sieve says the project’s biggest construction challenge was replacing three spans of the bridge.
“Although each replacement occurred several months apart, the work required the collaboration of many entities, including all rail companies served by TRRA, the U.S. Coast Guard and the U.S. Army Corps of Engineers. ‘US Army,’ it says.
The new spans were built by Veritas Steel in Eau Claire, Wis., and shipped to St. Louis for final assembly.
The existing armor is demolished on the MacArthur Bridge.
Photo courtesy of TranSystems
Preparing for evolving needs
The second phase of the $15 million rehabilitation of the MacArthur Bridge, which is just south of the Merchants Bridge, will rehabilitate the main spans and the eastern approach. It is scheduled to be completed in 2026.
“The MacArthur Bridge is a second generation truss span over the Mississippi River. The trusses are designed with nickel steel which is more corrosion resistant than the Merchants Bridge, but not all of its elements were,” he says Fields. “The floor system, which is under the track, is what we focus on [in Phase 1] because back then it was made of regular steel and had a shorter lifespan.”
Both projects are designed to meet the evolving needs of railways.
“The trend in rail today is to not let infrastructure be a constraint and build the infrastructure to handle heavier and wider railcars,” says Fields.
The new bridges are capable of supporting rail cars weighing up to 315,000 pounds compared to the current standard of 286,000 pounds. They can also handle wagon widths of 15 feet compared to their previous limit of about 13.5 feet.
The loss of one of the bridges would have negatively affected economic growth.
“We need more rail capacity to handle the growth of the country, and the loss of one of these Mississippi River bridges would be a problem for congestion on other networks, even in Chicago,” Fields says. “There’s a lot of overflow from Chicago to the St. Louis area when loading [in Chicago] is backed up. Having these river bridges is a great asset to the whole network.”
Walsh Construction is erecting the east span of the Merchants Bridge using a gantry system.
Photo courtesy of The Terminal Railroad Association of St. Louis
Addressing obstacles to funding
For both bridges, an even bigger challenge was raising the funding for the projects. TRRA’s process included the development of an asset management plan for long-term financing, projections of the impact of the proposed improvements on the economy, and approval of the plan by five Class 1 railroads that they fund the association’s operations through fees to use its bridges and other infrastructure.
Wood credits Fields with coming up with an accurate budget for the Merchants Bridge replacement.
“There is a lot of history here. It didn’t seem like a big stretch to at least keep some of it.”
—Brent Wood, President and Chief Financial Officer, TRRA
“We budgeted for the project in 2016, and when we finished the project, [the budget] it was true We actually came in under budget, which is unusual when you’re talking about seven to eight years to finish,” says Wood.
While replacing the bridges was a major undertaking, Fields says coordinating with the many different entities involved was an even bigger success.
“To get five Class 1 railways to come together on an issue of [replacing] a major asset was a hit,” he says.
Looking ahead, Fields predicts the Merchants Bridge will last more than 100 years.
Remembering the past
Although the future for freight on the Mississippi in St. Louis looks bright, TRRA has not forgotten the past. He saved a medallion from the original bridge that he donated to the National Transportation Museum in St. Louis. He also coordinated with Walsh to save some of the scrap metal he’s giving to artists to turn into sculptures or other works of art.
“There’s a lot of history here,” says Wood. “It didn’t seem like a big stretch to at least keep some of it.”
