
Below 15, the level that requires action
2 public water companies list Johns Island (Sta.) as a place they supply. The biggest is St John'S Water (Sc1020002), with about 22,592 people. The highest latest result among Johns Island (Sta.)'s water companies is 2 parts per billion, at St John'S Water (Sc1020002). None of the 2 with results was above 15 at its latest test.