FALMOUTH — A two-day effort to check for impaired boaters over the weekend yielded no charges, but did lead to the rescue of a kayaker in Casco Bay.

Falmouth police and the Portland harbormaster rescued a 25-year-old man near Cow Island who had fallen out of his kayak and was struggling to stay afloat without a life jacket in the chilly water between 7:30 p.m. and 8 p.m. Saturday.

“They definitely feel this kid would have drowned” had help not arrived, said Lt. John Kilbride.

Rescuers also retrieved the man’s companion, whose kayak was taking on water and who also did not have a life jacket.

The events occurred while Falmouth police participated in Operation Dry Water, a national effort to check for drunken boaters, over the weekend. Police checked 84 boaters and found none in vioIation, Kilbride said.