Rick Karr, Blueprint America correspondent

The most vocal opponents of Birmingham’s Northern Beltline have been environmentalists. They’re concerned that the highway will lead to sprawl and spread air pollution to the mostly-undeveloped land north of the city. But they’re especially worried about the effects that the road will have on two river basins –- the Cahaba and the Black Warrior –- which together provide most of the metropolitan area’s water supply.

Blueprint America spent an afternoon with Nelson Brooke, executive director of Black Warrior Riverkeeper, walking along Patton Creek, beneath Birmingham’s existing Southern Beltline. The stream is a tributary of the Cahaba, joining it downstream of the intakes for Birmingham’s water supply. Nonetheless, Brooke said it offered a good overview of the effects that highway construction –- and the commercial development that it causes –- have on streams and rivers.

Brooke and other environmentalists don’t want what’s happening to Patton Creek to be duplicated in northern Jefferson County. And they say the federal government is on their side: The U.S. Environmental Protection Agency wrote in 1997 that the chosen alignment for the Northern Beltline “has the most impacts on natural resources” of any of the alternatives that the State of Alabama considered –- disrupting streams at 14 crossings, impacting more that 4,000 acres of forest, and destroying 68 acres of wetlands.

Advocates for the highway have taken aim at environmentalists: A coalition of businesses that pushes for the Northern Beltline calls the green groups “no-growthers” who want “onerous regulations”. Nelson Brooke denies the charge. “I’m a strong advocate for low-impact development,” he told me. “The type of development we are seeing around our Interstates is the exact opposite of that. It’s sprawling. It’s in total disregard of the natural environment and how it’s disrupting it. And so I would say I am anti- that sort of development, but not anti- any and all development.”