When someone is injured in an organized event - in boating this is typically a raft-up, fishing tournament, poker run, or regatta - they are considered to have "assumed the risks" that go along with that activity. In the words of the Court, "a sports participant assumes all risks incidental to the sport which are obvious and foreseeable, i.e., the usual and foreseeable dangers that a participant expects to encounter." This is true whether or not the participant signs a written waiver. In the Maryland cases, this meant that a youth playing second base in softball assumed the risk that a player could slide into her and break her ankle. Similarly, a weightlifter assumed the risk that he could drop the weight during a lift attempt and injure himself. In a fishing tournament, a participant would be considered to assume the regular risks of fishing - probably everything from hook injuries to drowning. In a poker run, high speed would be included, and in a sailing regatta it would probably include bad weather or being hit by the boom. The more experienced a participant is, the more it is expected that the person is aware of the risks.
In 2006, Maryland's middle appellate court, the Court of Special Appeals, held that that risks that go beyond the regular and foreseeable risks of the activity are not necessarily assumed by the participant. For the weightlifter, the court found that specific instructions to the spotters who were supposed to catch the weight, saying not to touch the bar unless signaled by the judge, were not normal. Since the instructions were not normal, and created an enhanced risk, the injured weightlifter could go forward to try and prove that part of his case.
For organizers of water based sports and activities, this "enhanced risk" doctrine presented a dilemma, because it indicated that the more organizers did to try to prevent injuries, the more they might create unusual and unknown risks. Maryland's highest court, the Court of Appeals, however, clarified this issue in 2007. It rejected the notion of "enhanced risk" and held that participants assumed the risk of all negligence (including negligent training and instruction of those working the event), and that only reckless or intentional conduct could bring liability. This greatly reduces the risks to event organizers, since reckless or intentional conduct is much less frequent than negligence.
Overall, injuries on the water are pretty rare, and often involve obvious risks like drinking alcohol and swimming at night. Organizers should of course use caution, and should encourage their participants to do the same. They need not worry, however, that mere negligence will give rise to a successful lawsuit.
As always, these comments are of a general nature, and if you or your organization needs answers to specific questions, you should hire a Proctor in Admiralty.