Van Cleaf was born October 8, 1979, to father Garrett W. Van Cleaf and mother Phebe M. Van Cleaf in Northfield, New York on Staten Island, though he spent much of his later life in greater Brooklyn. By the age of 15, he had become well-known in the local swimming community for winning and placing well in swimming competitions. In addition to later training in the pool at the
New York Athletic Club, he trained by swimming in the ocean at Bath Beach, near his place of residence in Brooklyn. Not discouraged by the cold, he swam frequently in the early spring after ice had left the water's surface. Van Cleaf initially swam for New York's Knickerbocker Club, but after it relocated, he joined the accomplished New York Athletic Club, where he became well-known in the swimming community. On February 27, 1904, Van Cleaf's New York Athletic Club water polo team defeated the team from Massachusetts' Brookline Swimming Club 7-1 at the Central Park South Clubhouse, though the results of the swimming contests were closer. Van Cleaf placed third in the 100-yard swim event behind Harry Le Moyne, whose time of 1:02.4 was one second off the American record owned by Le Moyne, and C.M. Daniels. ==1904 St. Louis Olympic gold==