(a) Upon receipt of a written complaint, the District Commander will review the complaint to determine if, in the District Commander's opinion, the complaint is justified and whether a Preliminary Investigation is warranted.

(1) The District Commander's opinion as to whether or not the complaint warrants a Preliminary Investigation will be formed through informal discussions with the complainant, users of the affected waterway, the owner of the bridge, and other interested parties.

(2) In forming an opinion, the District Commander may also review the district files, records of accidents, and details of any additional written complaints associated with the bridge in question.

(b) In the absence of any written complaint, the District Commander may decide, based on a bridge's accident history or other criteria, to conduct a Preliminary Investigation.

(c) The District Commander will inform the complainant and the Chief, Office of Bridge Programs of the determination of any Preliminary Review. If the District Commander decides that the bridge in question is not an unreasonable obstruction to navigation, the complainant will be provided with a brief summary of the information on which the District Commander based the decision and will be informed of the appeal process described in § 116.55. There will be no further investigation, unless additional information warrants a continuance or reopening of the case.