The recent South Carolina v North Carolina case from the U.S. Supreme Court confirmed the test that non-state interveners must pass to take part in an action based on the Court's original jurisdiction between two or more states.
According to Jeff Kray from Marten Law who provides a detailed analysis of the case, this is a significant decision notably because it can have the following effect:
«The Supreme Court’s procedural decision in South Carolina v. North Carolina opens the door to private water users to intervene in water resource disputes between states and foreshadows more active private party involvement in such cases.»
More involvment from private actors might mean, on one hand, that stakeholder participation could increase and ultimatly reduce the importance of artificial state boundaries superimposed on natural watersheds, but on the other hand, it might also mean increased costs and delays in resolving water disputes as well as comparative disadvantage for poorer water users.
Finally, because the test for non-state actor involvment is not tied in some way to the states' use of their legislative and administrative power to apportion water within their own jurisdiction, increased non-state intervention might ultimatly result in a need for additional jurisprudential developments to clarify the states' role and powers in water apportionment.