A Birmingham-based river advocacy group that patrols waterways across West Alabama is among five conservation organizations suing the U.S. Army Corps of Engineers over a federal permit that a proposed natural gas pipeline would use to cross more than 1,300 streams, rivers and wetlands along its route. Instead, it challenges the Corps' 2026 renewal of Nationwide Permit 12, a general federal permit that lets pipeline builders cross waterbodies without a project-specific review or public comment period. At the center of the case is the South System Expansion 4 project, or SSE4, a natural gas pipeline expansion that would run through Mississippi, Alabama and Georgia. The pipeline is also under review by the Federal Energy Regulatory Commission, which oversees interstate natural gas pipelines. Together with the Mississippi Crossing project, a separate pipeline proposed by Kinder Morgan subsidiary Tennessee Gas Pipeline, the two would lay nearly 500 miles of new pipe.