Wright Brothers Construction Carves Through Mountains for Birmingham Northern Beltline
The $5.3 billion Birmingham Northern Beltline, when complete, will provide motorists with an alternative to bypass city traffic and will create opportunities for economic growth and prosperity. Meanwhile, Wright Brothers Construction Company has carved through two mountains in preparation.
“This is the first project of the Birmingham Northern Beltline, and we are excited to be part of it,” says J. Mitchell Simpson, Vice President and Chief Operation Officer of Wright Brothers of Charleston, Tennessee. “We know for years to come we can do more work on this project.”
In its entirety, the 52-mile long, six-lane limited-access highway will stretch from Interstate 59 in northeast Jefferson County to the I-459 interchange with I-20/59 near Bessemer. The project was initially planned and approved by the Federal Highway Administration in the 1990s. The Alabama Department of Transportation (ALDOT) estimates the entire project should be completed by 2054. Portions will be let as funding becomes available.
“We have a southern Beltline in place, and this will be the northern loop around the city,” says Gary Smith, ALDOT construction engineer for the Birmingham area. “This is a huge project, and this is just the beginning.”
Projects on the beltline authorized by September 30, 2021, are eligible for 100 percent federal funding with no matching state funds, due to Congress making the Appalachian Development Highway System a priority. Congress has designated the beltline as a national priority.
AECOM, based in Los Angeles, but with offices in Birmingham, designed the beltline.
Carving Out a Road
Wright Brothers began construction on the $46 million grading project in September 2014 and is on tract to complete the project this summer. This first project, between state highways SR 79 and SR 75, cuts through two mountains as high as 150 feet. One of the cuts required a permanent soil nail wall. Wright Brothers would excavate and then subcontractor Russo Corp. of Birmingham would drill anchors and apply the shotcrete.
“That was slow and tedious,” Simpson said. “That took some time due to the coordination and sequencing between us and Russo. I think it went well.”
According to ALDOT, soil nailing is a “construction technique that allows the safe steepening of new or existing soil slopes. The technique generally involves the insertion reinforcing elements into the slope, tensioned and secured with soil nail head plates, and the slope face covered with pneumatically applied concrete.” The soil nail wall, with a pneumatic concrete blanket, is complete, and is 150 feet at the tallest point.
The other major cut was drilled and blasted. Wright Brothers used a PC1250 Komatsu Excavator to remove the dirt and rocks. Crews placed the dirt in Caterpillar 777 Off-Highway Trucks and hauled the waste material to a nearby site the contractor secured.
“You don’t want to move it far, especially with those types of trucks,” Simpson says.
To keep dust down, Wright Brothers used a Caterpillar water truck.
Wright Brothers removed 2.4 million cubic yards of dirt. Some cuts were deep and extremely wide, Smith reports. In many locations, ALDOT decided to add retaining walls, so less material would have to be excavated and hauled away.
The company also has completed a culvert that extends under Highway 79.
Environmental and Archeological Challenges
The road passes through an environmentally sensitive area and before construction even began the DOT knew through preconstruction surveys that the path contained some spear points dating back to 8,000 B.C. and fragments of a bottle dating to the late 1800s. Archaeologists from Panamerican Consultants of Tampa, Florida, gathered items to help preserve history of the area. Artifacts collected went to a state curator. The road ran next to the sites. ALDOT took steps to mitigate any disturbance of the historical artifacts by adjusting the slope of the cuts.
ALDOT also developed a plan to protect the environment. There were no threatened or endangered species in the construction area when the project started in 2014, but in May 2015, the Fish and Wildlife Service listed as threatened the northern long eared bat. ALDOT is coordinating with the service to avoid disturbing the bat.
The agency did not want any stormwater leaving the site and came up with innovative ideas to gather the water and minimize runoff. Simpson credits that good design with avoiding polluting the nearby waters. He says the basins have been effective. ALDOT plans to keep those basins and use them as retention ponds for the road.
Smith also reported the runoff control plan was done well and no fish were affected. ALDOT and inspectors are monitoring water quality.
“We put in a lot of sediment basins for the project to ensure no construction stormwater run off got into any of the streams,” Simpson says. “The erosion control was more strenuous than what we see on most projects.”
The environmental group Black Warrior Riverkeeper challenged the beltline’s permitting processes, maintaining that the entire route should have an environmental impact review rather than one section at a time. But the U.S. District Court ruled in January 2016 that ALDOT was not required to perform that analysis.
Three bridges will be built in this section on a different contract. Another contract will be let to pave the road with asphalt. As work progresses, ALDOT will continue to conduct environmental studies to supplement earlier investigations. ALDOT is conducting field surveys and investigating soil and rock characteristics on other sections of the beltline. The agency also will continue with preliminary engineering, design and purchase of right-of-way land.
“It’s been a good job for us and we have had a good relationship with the Alabama DOT on this project,” Simpson concludes. “We look forward to doing another job with them on the Northern Beltline.”