The Columbia Neighborhood Swim League (CNSL) is a summer recreational swim league with 14 swim teams located throughout the Columbia, Ellicott City and Clarksville areas. CNSL is open to swimmers 18 years old or younger with all ability levels who meet the League Requirements.  Columbia Association provides coaches, facilities and a framework for CNSL participants to improve swimming abilities, develop good sportsmanship and test performance in actual competition as part of a team in a safe and supportive learning environment.