The goal of the Clean Water Act is fairly straight forward: to protect and restore the waters of the United States. But what counts as "waters of the United States" is often a tricky and highly contentious question. And if federal agencies determine that your isolated marsh, seasonal ponds, or agricultural slough are subject to regulation under the act, then a whole host of legal restrictions can suddenly apply. Yet, you may not be able to challenge that determination until years in the future.
That is to say, CWA disputes can quickly get a bit murky. The Supreme Court jumped right into those muddy waters today, in its first major environmental case since the death of Justice Scalia. The court heard arguments in a challenge to CWA determinations that blended environmental and administrative law with questions of justice and jurisdiction.