Since the beginning of April, more than 80 people have drowned nationwide, broadcaster TVN24 reported, citing police statistics.
According to officials, alcohol is among the main causes of swimmers drowning in Poland.
Deaths often occur in bathing areas not patrolled by lifeguards.
The Government Centre for Security on Monday warned people in a Twitter post that they should not drink or take drugs before going swimming.
It also appealed to citizens to steer clear of unguarded beaches and to wear a life jacket when on a boat or canoe.
With Thursday, June 11, a public holiday, many Poles took Friday off to enjoy an extended break from work amid an easing of coronavirus restrictions.
(gs)
Source: TVN24