A stretch of the Birmingham highway that would eventually link up with the Northern Beltline. Photo: WNET.org

What is a "zombie highway"? Exactly what the name suggests: a road that won’t die, swallowing government funds and congressional earmarks while posing potential harm to those who live near it.

Tonight the Blueprint America segment of PBS’ NewsHour takes a look at a quintessential zombie, the Northern Beltline of Birmingham, Alabama. Transportation wonks of all stripes are encouraged to tune in — but here’s a preview of the issues explored by Blueprint correspondent Rick Karr.

The Beltline is part of the Appalachian Development Highway System (ADHS), a 44-year-old project intended to spur economic modernization in the mountainous region. But in the decades since, lawmakers have been unable to resist "Christmas tree-ing new roads into the program," Karr told Streetsblog Capitol Hill.

A classic Christmas-tree move was employed to designate the Beltline as Corridor X-1 on the ADHS, which has received $470 million annually since 2005. Sen. Richard Shelby (R-AL) quietly inserted language into a 2004 spending bill bringing the highway into the ADHS after helping secure $60 million for the local metropolitan planning organization to buy rights-of-way.

Some local residents, however, formed a group dubbed SOURCE to shed light on the state DOT’s environmental review. In particular, SOURCE questioned the choice to complete Birmingham’s northern belt using the outermost possible road, running through the headwaters of two rivers that provide much of the city’s drinking water.

The Environmental Protection Agency (EPA) concurred, Karr said, telling Beltline planners that "we think you’ve chosen the wrong alignment." But the alignment looked right to companies such as U.S. Steel, which has partnered with the city’s Chamber of Commerce to help push for speedy funding of the road.

U.S. Steel also recently bought up more than 300 acres of undeveloped land one mile away from the proposed road.

As Karr found, SOURCE is not alone in viewing the Beltline as a zombie plaguing the federal transport system. House transportation committee chairman Jim Oberstar (D-MN) added a section to his recent six-year federal infrastructure bill that would limit Washington’s total share of Beltline costs to $500 million, language that Karr described as an attempt to "stop other Appalachian senators" from following in Shelby’s footsteps.

Still, Shelby’s fellow Alabama Republican, Rep. Spencer Bachus, is undaunted.

"Our funding is set, and this highway is going to be built. I would say faster than normal because of designated revenue," Bachus — who is seeking a $2 billion earmark for the beltline in the upcoming six-year transportation bill — told the Birmingham News in May.

Karr’s full report will be available online tomorrow on Blueprint America’s site after its NewsHour premiere tonight.