A case argued before the U.S. Supreme Court spotlights some puzzling ambiguity in the Clean Water Act. In Sackett v. EPA, Idaho landowners believe the Environmental Protection Agency has no right to regulate wetlands on their land. They say it is not a “WOTUS” – or Water of the United States – since the closest lake is across a road and about 100 yards away.

Several questions arose in the recent hearing, including whether the wetland is legally “adjacent” to a lake. Justice Neil Gorsuch, for example, said he needed to understand “how much adjacency is adjacent?”

Taft Atlanta Environmental attorney Stephen McCullers told E&E News Greenwire, which covered the arguments, the justices did not seem to favor the landowners’ argument that only wetlands with a continuous surface water connection to traditional waters should face federal permitting. To find more on the case, and why it matters to developers, farmers and environmental groups, click here.