Swimming does not need a "Catholic Priest" problem. No organization wants that problem.
Unfortunately, I cannot find a USA Swimming prevention policy that protects both coaches from false accusations or children from predators, but I did find a Boy Scouts of America (BSA) prevention policy that ostensibly could protect both kids and scout leader reputations. (I am not saying that USA Swimming does not have one, I just can't find it!)
I am copy/pasting the BSA policies here with my reccomendations as to how to make it applicable to a swim coach/age-group swimmer relationship in bold:
Two-deep leadership. Two registered adult leaders or one registered leader and a parent of a participant, one of whom must be 21 years of age or older, are required on all trips and outings. The chartered organization is responsible for ensuring that sufficient leadership is provided for all activities. [A parent or two should sit through a workout and a swim meet.]
No one-on-one contact. One-on-one contact between adults and youth members is not permitted. In situations that require personal conferences, such as a Scoutmaster's conference, the meeting is to be conducted in view of other adults and youths. [Parents must be involved for one-on-ones if an adult can be there]
Respect of privacy. Adult leaders must respect the privacy of youth members in situations such as changing clothes and taking showers at camp, and intrude only to the extent that health and safety require. Adults must protect their own privacy in similar situations. [That's clear enough]
Separate accommodations. When camping, no youth is permitted to sleep in the tent of an adult other than his own parent or guardian. Councils are strongly encouraged to have separate shower and latrine facilities for females. When separate facilities are not available, separate times for male and female use should be scheduled and posted for showers. [That's clear enough]
Proper preparation for high-adventure activities: Activities with elements of risk should never be undertaken without proper preparation, equipment, clothing, supervision, and safety measures. [Medical checkups, and back-up swimsuits and Goggles.]
No secret organizations: The Boy Scouts of America does not recognize any secret organizations as part of its program. All aspects of the Scouting program are open to observation by parents and leaders. [A parent or two should sit through a workout.]
Appropriate attire: Proper clothing for activities is required. For example, skinny-dipping is not appropriate as part of Scouting. [That's clear enough]
Constructive discipline: Discipline used in Scouting should be constructive and reflect Scouting's values. Corporal punishment is never permitted. [Values here should be about health, welfare, growth and most important - having fun!]
Hazing prohibited: Physical hazing and initiations are prohibited and may not be included as part of any Scouting activity. [That's clear enough]
Junior leader training and supervision: Adult leaders must monitor and guide the leadership techniques used by junior leaders and ensure that BSA policies are followed. [Encourage policies such as these be adopted by swim clubs.]
For more detailed information, here is link to the BSA page on the subject.