Section 16. Every authority or license granted since eighteen hundred and sixty-eight by the general court or by the department or its predecessors to any person to build or extend a wharf or other structure upon, or to drive piles in, or to fill or otherwise occupy, land in tide or navigable water, within Boston harbor, or within the port of Boston as defined by the provisions of section two of chapter ninety-one A, which is revocable at the discretion of the general court, and every other similar right or privilege within Boston harbor or within the port of Boston as defined by the provisions of section two of chapter ninety-one A which is so revocable, whether or not compensation has been paid under any provision of law or otherwise, shall hereafter cease and determine, or be subject to forfeiture, in case of non-use of the same for an unreasonable time without reasonable cause, and it shall be prima facie evidence that the same is held unused in restraint of trade when the tendency of such non-use is to prevent competition in its broad and general sense, unless such person has, prior to July twenty-eighth, nineteen hundred and twelve, made reasonable and substantial use of structures, or has reasonably and substantially occupied land in tide or navigable waters, for the purposes for which the authority or license was granted; and thereupon, every such authority or license and every similar right and privilege shall cease and determine on repayment, or tender of repayment, by the commonwealth or compensation therefor to the amount which shall have been paid to the commonwealth in accordance with the terms of such authority or license; and the department and the attorney general shall cause a proper certificate of the revocation of such authority or license to be recorded forthwith in the registry of deeds for the county where such structure was built or work done.