N.J. Stat. Ann. § 48:5-24

If the state, acting jointly with any adjoining state, shall not have purchased a bridge constructed by a company organized under this article at the expiration of fifty years after the opening of the bridge for public use, the bridge together with the necessary approaches and appurtenances shall become the property of such states for public use without cost or expense to the states and the right, title and interest of the company shall cease.