Growth slowed after the 60s, but the league continued to expand. Eighteen new teams joined the MCSL in the 1970s, most in newly-developed areas of the county. Dates in parentheses are the last year a team competed.
1971--no new teams
New Mark Commons
Stedwick (2003--most swimmers went to Whetstone)
Watkins Mill (merged with Stedwick)
1975--no new teams
Northgate (1999--most swimmers went to North Creek)