The 74-year-old man may have been fishing at his waterfront home near Shiloh Avenue and Park West Drive, according to his wife who told authorities she had last seen him at about 6:30 p.m. Sunday.
When the man's wife went to check on him two hours later, she found his walker on the dock and shoes in the water, according to Texas City Fire Department Battalion Chief Micah Simons.
The man, whose identity has not yet been released, had Parkinson's disease and other health issues, officials said.
Texas City police searched the lake and the shoreline Sunday with a night vision camera but did not find him.