This is the info from the wildlife resources site about reporting accidents it starts with the header Accidents must be reported. I assume that means if they meet the criteria below.
Accidents Must be Reported
Any boating accident involving death, or injury requiring medical treatment beyond first aid, or the disappearance of a person should be reported as soon as possible, and must be reported within 48 hours.
All accidents involving property damage in excess of $500 (to one vessel or a combination of both vessels) must be reported within 10 days.
The operator of every vessel involved in a reportable boating accident is required to file an accident form with the TWRA. Accident report forms are available from any TWRA office. Failure to report a boating accident is a criminal offense and may result in prosecution by the TWRA.
Giving assistance is required. Whenever a boat is involved in an accident, it is the duty of the operator to give necessary assistance, as long as it will not personally endanger the operator, the passengers, or vessel.
Incidents Involving Serious Injury or Death: Vessel operators involved in incidents where persons are seriously injured or killed may be charged with a felony resulting in a fine of $10,000 and 15 years imprisonment.
http://state.tn.us/twra/boat001.html