§ 18. Special navigation inspectors. The commissioner may, if in his judgment conditions so require, appoint members of local boat clubs, or other persons found competent, to act as special navigation inspectors during regattas authorized by him. The power and authority in such special navigation inspectors shall be limited to the period during which the regatta is authorized and to the enforcement of the navigation law and special regulations. Upon the completion of the regatta, he shall file with the commissioner a report covering the conduct of the regatta and his activities. Such special navigation inspector shall receive no compensation from the state. Any expense in connection with his duties shall be borne by the person conducting the regatta.