The Board of Commissioners of Navigation for the river Delaware and its navigable tributaries shall have jurisdiction to make rules for regulating the speed of vessels navigating the Delaware River and its navigable tributaries, between Marcus Hook and Bristol, in the State of Pennsylvania: Provided, That such rules shall not extend to, impair, or in any way infringe on, the mutual arrangements entered into by this State and the State of New Jersey.
55 P.S. § 401