<current> indicates the strength of the current during a dive. Allowed keywords are: no-current, very-mild-current, mild-current (no problem to swim against it), moderate-current, hard-current (even for trained divers it is possible to swimm against it only for a short period of time), very-hard-current (it is not possible to swim against it, even trained divers cannot).
<current> appears inside the <dive> section for it describes the strength of the current during a specific dive, not the general condition at a dive spot.