Deputies responded to Mayfield Lake, off Highway 122 near Mossyrock, on Tuesday afternoon after receiving a 911 call about a possible drowning, said Lewis County Sheriff Steve Mansfield.
A witness told deputies that he and his friend, the missing man, had been swimming in the area of Ike Kinswa State Park boat launch. The two men were jumping from a 30-foot cliff into the water.
The witness said he heard his friend hit the water, but when he turned around he could not see him. He swam to shore and then spent about an hour searching the lake bank for his friend.
The witness then returned home and called 911 to report the incident. He told deputies that both he and the missing man had been consuming alcohol before jumping into the lake.
Emergency responders from the Lewis County Sheriff Swift Water Rescue Team, Fire District 3 and Fire District 8 searched the area until nightfall with no success.
The water temperature was 62 degrees and the water at the location was over 100 feet in depth.
Deputies will continue to search the area today to attempt to locate the missing man, Mansfield said.