[JURIST] The US Supreme Court [official website; JURIST news archive] ruled Monday that New Jersey and Delaware have "overlapping authority" to control "extraordinary" construction projects along the Delaware River. The Court's decision came in New Jersey v. Delaware [Medill case backgrounder; JURIST report], where the Court revisited the century-old water boundary dispute between the two states. New Jersey filed a lawsuit [JURIST report] against Delaware in 2005 over British Petroleum's plans to build a liquefied natural gas plant on New Jersey's side of the Delaware River. Delaware refused to approve construction of a 2,000-foot pier that would serve the facility. Under boundary determinations settled by the Supreme Court in 1934 in New Jersey v. Delaware, Delaware controls the river up to the mean low-tide mark on the New Jersey shore, but New Jersey asked the Court to declare that a 1905 interstate compact gives it the right to control riparian access and structures on its side of the river, even if they extend across the border. A Court-appointed Special Master found [report, PDF] in 2007 that Delaware has the authority to block the pier.

The Court agreed with the Special Master's report, writing:

We accept the Special Master's recommendation in principal part. Article VII of the 1905 Compact, we hold, did not secure to New Jersey exclusive jurisdiction over all riparian improvements commencing on its shores. The parties' own conduct, since the time Delaware has endeavored to regulate coastal development, supports the conclusion to which other relevant factors point: New Jersey and Delaware have overlapping authority to regulate riparian structures and operations of extraordinary character extending outshore of New Jersey's domain into territory over which Delaware is sovereign.

The Court concluded:

Given the authority over riparian rights that the 1905 Compact preserves for New Jersey, Delaware may not impede ordinary and usual exercises of the right of riparian owners to wharf out from New Jersey's shore. The Crown Landing project, however, goes well beyond the ordinary or usual…. Consistent with the scope of its retained police power to regulate certain riparian uses, it was within Delaware's authority to prohibit construction of the facility within its domain.

Read the Court's opinion [text] per Justice Ginsburg, along with a partial concurrence and partial dissent [text] from Justice Stevens and a dissent [text] from Justice Scalia. Justice Breyer did not participate in consideration or decision of the case. AP has more.