I revised the definitions page at http://www.airsafe.com/events/ditch.htm to include the following definition for ditching:
An event where the flight crew intentionally lands an aircraft in some body of water such as a lake, a river, or the open ocean. In addition, the event would have to meet the following conditions or criteria:
- Accidental or unintentional landings or excursions onto water are excluded, such as runway overruns or controlled flight into water.
- Uncontrolled impacts with water are excluded.
- The body of water must be deep enough that if the aircraft sinks, some or all of the occupants would have to evacuate the aircraft cabin to avoid drowning.
This definition is consistent with how AirSafe.com has always defined ditchings. If you believe that the definition needs further work, by all means leave a comment to this post with your suggestions.