Bill Halpin is the head coach of the Merced College Women's Water Polo Team. He graduated from Merced High School in 1967. In 1965-1967 he was the Central California Section Swimming Champion in both the 400-yard Freestyle and the 200-yard Individual Medley.

Halpin graduated from Merced College in 1969, attended Fresno State, lettering in swimming and water polo, and graduated with a degree in recreation and physical education.

He obtained his M.A. degree from Chapman University in 1976. He was the first coach of the water polo team at Merced High School in 1973, and coached there for eleven years, with an overall record of 224-35. His team was the CIF champion in 1982. His teams were also the League Champions for five consecutive years between 1979 and 1983. Halpin's high school team also won the 19-and-under junior national championships in 1982 in Honolulu, Hawaii. He started the girls water polo team in 1979 at Merced High School. After coaching for many years, in 1985 he was inducted into Merced County Hall of Fame.

He has been a water polo referee for over ten years and has been associated with the women's water polo team at Merced College for the past twelve years, during which time their record has been 301-101. The Merced College team has finished in the top seven in the entire state of California nine out of twelve years. Bill was named Conference, NorCal, and State Community College Coach of the year in 2001, and in 2003 Nor-Cal Coach of the Year. He also is the head coach of the women's swimming team that captured the 2006 Bay Valley Conference Championship.