The U.S. Supreme Court on Nov. 27 heard oral arguments over whether Delaware can block a $700-million liquefied natural-gas import terminal from being built off a pier on New Jersey’s side of the Delaware River. The two states have been debating“riparian jurisdiction” since Colonial times.

In 2005, Delaware denied BP America’s permit request for a LNG terminal extending past the lowwater mark on New Jersey’s side of the river.

Related Links: Transcript of Oral Arguments

New Jersey’s attorney, H. Bartow Farr, said a 1905 bi-state compact limited Delaware’s ability to interfere with New Jersey projects, including those reaching into Delaware waters. But Delaware’s attorney, David C. Frederick, argued the terminal would violate state environmental laws. He said Supreme Court precedent has established that “police power trumps…riparian rights.”

The justices questioned the extent to which Delaware may exercise jurisdiction over another state, but it was unclear how the court will rule. A decision in the case, New Jersey v. Delaware, is expected in 2008.