The Department of Forests and Waters, acting directly or through the Water and Power Resources Board, and, in the case of Lake Erie, by or through the Pennsylvania State Park and Harbor Commission,¹ is hereby invested with power and jurisdiction to determine, as a fact, when any such right, grant or privilege has become, or is to be deemed, derogatory or inimical to the public interest, or fails to serve the best interests of the Commonwealth. Any such determination shall only be made after full hearing, of which the person, firm or corporation, having or claiming the right, grant or privilege, shall have due notice and an opportunity to be heard. If, after such hearing, the Department of Forests and Waters, the Water and Power Resources Board or the State Park and Harbor Commission shall find and determine that any such right, grant or privilege is derogatory or inimical to the public interest, or fails to serve the best interests of the Commonwealth, such right, grant or privilege shall be deemed to be revoked, pursuant to section one hereof, and, upon service of the order of revocation in the manner in which a summons of the court of common pleas is served, the right, grant or privilege possessed in the bed of such navigable waters shall cease and terminate.