A 29-year-old swimmer drowned in the waters off Orchard Beach in the Bronx Wednesday evening, authorities said.

Adolfo Muñoz, of the Bronx, was pulled out and rushed to Jacobi Medical Center, where he was pronounced dead.

Muñoz was believed to have been with his wife and son when he went into the water and began to struggle at 7:30 p.m., witness Kenny ­Estrella told The Post. Estrella said he other beachgoers tried to help him.

“I saw like a huge wave. It looked like he sank,” ­Estrella said of the victim.

“We couldn’t pull him out . . . I really tried my best but we couldn’t get him out. His body just sank.”