On April 1, 1989, the Hatchie Bridge in Tipton County, Tennessee, collapsed from the pressure of the shifting river channel, killing eight motorists and sparking an investigation into the state's failure to inspect and correct problems with the bridge a decade earlier.
Thirty years later, as Tennessee Department of Transportation crews were busy fixing a partial bridge collapse on the Interstate 75 South overpass in Chattanooga that seriously injured one motorist, TDOT deputy commissioner and chief engineer Paul Degges remembered it was the anniversary of the Hatchie Bridge collapse.
Top 5 most traveled structurally deficient bridges in Hamilton County:
*Information provided by American Road & Transportation Builders Association
Degges, who was working in the hydraulics unit of TDOT in 1989, recalled that the Hatchie Bridge failure was like the "straw that broke the camel's back" for state officials.
"There had been a few things that had happened nationwide that really put a spotlight on the fact that not only do bridges link communities, but you can't just build it and walk away — you have to inspect it, maintain it and rehabilitate it," he said.
While a National Transportation Safety Board investigation in 1989 cited the state as failing to correct problems found on the 54-year-old bridge from previous inspections, the partial bridge collapse onto the merging lanes of I-75 North to Interstate 24 West headed to Chattanooga almost two weeks ago was not due to negligence by state transportation officials but from an illegally oversized load that hit the bridge and cut through steel cables.
After Hatchie, Degges said the state moved toward an "asset management philosophy," which calls on the state to fix and maintain current roads and bridges before spending money building new ones. The philosophy has seemingly paid off.
In 2018, about 4.3% of bridges in Tennessee — or 871 of the 20,177 bridges — were considered "structurally deficient," meaning one of the key elements was in poor or worse condition. The share of bridges judged to be deficient in Tennessee was less than half the U.S. average and ranks Tennessee among the best states for bridge infrastructure, according to the 2019 report from the American Road & Transportation Builders Association.
Only nine states and the District of Columbia have fewer structurally deficient bridges than Tennessee. About 4.3% of bridges in Alabama and only 3.3% of bridges in Georgia are structurally deficient.
In Rhode Island, which has the highest share of deficient bridges, roughly 23% of bridges — or 180 of the 780 — are considered structurally deficient.
Nationally, about 9% of bridges are considered structurally deficient.
"I will say from a nationwide perspective, there is a big problem with bridge infrastructure out there, but for Tennesseans, and certainly for our state highway system, the bridges are in better shape now than they have been in [TDOT's] 100-year history."
"Structurally deficient" is a scary-looking term for the average driver, Degges said, but most structurally deficient bridges are safe to drive on and there's not a risk of them collapsing.
But improvements could still be made. The state has identified needed repairs on 7,343 bridges at an estimated cost of $1.9 billion, reports the American Road & Transportation Builders Association.
While only 2.6% of the 8,300 bridges owned by TDOT are structurally deficient, 610 — or 5.3% — of the 11,400 owned by local governments across the state are considered structurally deficient, Degges said.
The national report states that in the 3rd Congressional District alone, 101 of the 1,902 bridges are structurally deficient — up from 84 bridges in 2014. Repairs are needed on 702 bridges, though, which will cost an estimated $254.5 million. The district includes Hamilton, Anderson, McMinn, Monroe, Morgan, Polk, Roane, Scott and Union counties and areas of Bradley and Campbell counties.
But while bridges are, for the most part, faring well in Tennessee, local municipalities are still feeling the strain of growing road congestion and not enough money to accommodate it all.
$3 billion needed locally
Funding for infrastructure has not kept pace with inflation, especially federal funding, which has not changed much in the last two decades, Degges explained.
"The bigger issue is that there are more miles driven every year than gasoline sold, and gasoline and diesel taxes fund the bulk of transportation programs," Degges said. "As people drive more, they are using more gas, but as vehicles become more fuel-efficient then the growth rate of revenue is not keeping up with the growth rate of miles traveled."
The three local metropolitan and transportation planning organizations — the Chattanooga-Hamilton County/North Georgia TPO, the Cleveland Urban Area MPO and the Greater Dalton MPO — have budget shortfalls for currently identified transportation projects totaling more than $3 billion.
"Almost any jurisdiction would tell you there is a lot of unmet need in terms of building and maintaining transportation infrastructure," said Greg Thomas, planning director and MPO coordinator with the Cleveland Urban Area MPO.
"That being said, we appreciate the value that our elected officials place on these facilities in approving the funding that they provide," he added.
For just the Chattanooga-Hamilton County/North Georgia TPO, there is a combined funding shortfall of $1.7 billion for 18 road capacity projects, 14 transit capacity projects and three bicycle/pedestrian projects in the 2045 Regional Transportation Plan.
When the bridge collapsed on I-75, Thrive Regional Partnership released a statement about the bigger issue of needing to improve infrastructure in the region and across the country.
The nonprofit is focused on promoting responsible growth for the next 40 years through the tristate Chattanooga region, which includes working with 16 counties in three different states and the three different metropolitan planning organizations.
With transportation and mobility a large focus of the organization, officials often cite how the intersection of I-24 and U.S. Highway 27 is listed in the top 100 freight bottlenecks by American Transportation Research Institute.
"It's easy to complain about outdated roads and potholes, but we should be cognizant that our infrastructure is far past a Band-Aid solution," the nonprofit's officials said in a statement. "In reality, updates and maintenance is years behind."
Gas tax increase to fund upgrades
When engineers concluded that an oversized tractor-trailer caused the bridge collapse on I-75 on April 1, it was another example of how freight can strain highway systems.
The American Trucking Association has mounted a new campaign to try to convince Congress to raise fuel taxes by a nickel a gallon every year for the next four years to help fund improvements on America's roads.
The ATA, the U.S. Chamber of Commerce and the AFL-CIO are among groups calling for a 20 cent-per-gallon increase in the federal fuel tax over four years to replenish the federal Highway Trust Fund.
The trust fund is nearly broke because the federal tax on gasoline has remained constant at 18.4 cents per gallon — 24.4 cents per gallon for diesel fuel — since 1993. Inflation has increased by more than 65 percent in the last 25 years, but as fuel mileage has improved on gasoline motors and more cars are battery powered, fuel taxes paid per vehicle continue to decline while road construction costs rise.
The proposed fuel tax increase, 5 cents a year for four years, would raise $340 billion over 10 years for road and bridge improvements.
At the state level, Gov. Bill Haslam signed into law the IMPROVE Act in 2017 that raised taxes at the pump to help fund 962 projects spread throughout the state's 95 counties.
David Parker, president of Covenant Transport and a member of the ATA executive committee, said he fully supports a fuel tax increase on Covenant's fleet of more than 7,000 trailers.
"Raise the taxes tomorrow and we will pay for it," Parker said. "Congestion is horrible and we see it right here in Chattanooga."
The ATA lists the intersection of Interstate 24 and Highway 27 near downtown Chattanooga as the 51st worst traffic bottleneck in America.
Nationwide, a study by the American Transportation Research Institute estimates traffic congestion costs the U.S. trucking industry $74.5 billion a year.
Parker said the trucking industry is one of the most taxed of any U.S. industry, paying more than $40 billion a year in highway user taxes.
"Through the highway tax fund we have funded it enough to build two or three interstate systems," Parker said. "That's what makes me mad. So we're saying that we will come to the table again to raise more money to fix and upgrade our roads. The only thing we want is to make sure that the money we raise [from higher gas taxes is] used for roads."
Study to begin on Chattanooga area's traffic trends, needs
Freight movement and how the greater Chattanooga region will accommodate it in the future has been a concern for many local officials. By 2035, there will be an estimated 33 million tons of freight per year traveling through the area, up from 25 million in 2007.
Recently, TDOT was awarded a $250,000 grant from the Federal Highway Administration to study and project future freight volumes across the Chattanooga region and to identify regional needs and solutions.
TDOT will work with the Alabama Department of Transportation and the Georgia Department of Transportation, local metropolitan planning organizations, trucking companies and even McKee Foods and Thrive Regional Partnership on the study that does not have a start date yet.
TDOT and its 22 partners were one of only four projects nationwide that were selected for the grant. Projects in Phoenix, Arizona; Kansas City, Missouri; and Nevada were chosen, too.
The study also will look at the region's need for more truck parking and capacity, said Rhett Bentley, Thrive's communications manager.
The area to be studied covers portions of the three states and 6,648 miles total.
"This grant was only available for multi-jurisdictional and untraditional partnerships," Bentley said. "The grant is a tangible example of how leveraging unique partnerships can secure federal dollars."
Contact staff writer Allison Shirk Collins at firstname.lastname@example.org, @AllisonSCollins or 423-757-6651. Business editor Dave Flessner contributed to this report.
Partners to participate in freight movement study:
*Information provided by TDOT