36 C.F.R. § 3.5
Do I have to report an accident involving a vessel to the National Park Service?
(a) The operator of a vessel involved in an accident must report the accident to the superintendent as soon as practical, but in any event within 24 hours of the accident, if the accident involves:
(1) Total property damage of $2000 or more; or
(2) Injury, or death or disappearance of a person
(b) If the operator is physically incapable of making the report, the owner or an occupant of the vessel must report the accident to the superintendent.
(c) Filing a report with the superintendent may satisfy applicable United States Coast Guard, State, and local accident reporting requirements. Superintendents will forward the accident report to the appropriate reporting authority in a timely manner that complies with the requirements of 33 CFR 173.55.