TRENTON, N.J. — A century-old legal and territorial dispute between New Jersey and Delaware is back in focus after a new bill introduced in the New Jersey Senate aims to formally revisit the boundary shared along the Delaware River and Bay.
Senate Bill S4671, entered by State Senator Mike Testa, proposes New Jersey’s participation in a “New Jersey-Delaware Territorial Boundary Adjustment Compact.” The legislation signals a renewed push by New Jersey to clarify or contest jurisdictional boundaries in one of the nation’s most unusual and historically contested state borders.
The border conflict dates back to colonial charters and was later addressed in the 1905 Interstate Compact, which attempted to define the rights of each state. In the most recent Supreme Court ruling in New Jersey v. Delaware (2008), the court sided with Delaware, affirming its control of subaqueous land up to the New Jersey shore in certain zones of the river and bay.
The 2008 case arose after New Jersey approved BP’s proposal to build a liquefied natural gas facility on its side of the river, which Delaware blocked under its Coastal Zone Act. The Supreme Court ruled 6–2 in favor of Delaware, with Justice Ruth Bader Ginsburg writing the majority opinion. “The 1905 agreement between the two states did not grant New Jersey exclusive jurisdiction over riparian improvements,” the Court found.
The decision upheld Delaware’s authority to regulate projects even when physically connected to New Jersey’s shoreline, due to the border’s unique delineation under a 17th-century grant that extends Delaware’s territory to the low-tide mark on the New Jersey shore in a 12-mile radius from New Castle.
Historic legal disputes inform modern legislation
Sen. Testa’s bill does not detail how the compact would alter existing boundaries or enforcement but reflects a pattern of recent legislative efforts by New Jersey lawmakers to assert stronger identification with the Delaware Bay region. The proposal follows another measure, S4670, which seeks to rename the Delaware Bay as the “Bay of New Jersey.”
“The New Jersey–Delaware Compact of 1905 … addressed the ‘exercise [of] riparian jurisdiction,’ and the power to ‘make grants … of riparian … rights,’” wrote Justice Antonin Scalia in his 2008 dissent, joined by Justice Samuel Alito. Both dissenters have ties to New Jersey.
The compact proposed by S4671 would likely require cooperation from Delaware and congressional approval to take legal effect. Neither Delaware lawmakers nor federal officials have yet commented on the measure.
Any new compact would have to contend with the precedent set by the 2008 Supreme Court decision, as well as the enduring structure of the original 1905 agreement between the two states. The compact’s language has not been publicly released in full.
New Jersey’s latest compact bill revives centuries-old territorial lines in one of America’s most peculiar and persistent border feuds.
