The Sterling Water Department recently completed the required annual lead and copper testing for twenty residential locations, Houghton School and Chocksett School. The results of the testing yielded three of the twenty residential locations above the action level for lead. The action level is the concentration of a contaminant in water which, if exceeded, triggers treatment or other requirements that a water system must follow. The action level for lead is .015mg/l. Our 90th percentile action level is .022mg/l. The action level for copper is 1.3mg/l. Our 90th percentile action level is .178mg/l. The results of the testing passed at both schools being below the action level. Please call the DPW 978-422-6767 with questions.