How much fluoride is added to the water?

The U.S. Department of Health and Human Services recommends a 0.7 mg/l optimal level of fluoride in drinking water to prevent tooth decay. The Portland Water District maintains an average of 0.70 mg/l. Recently, the Portland Water District was awarded the Water Fluoridation Quality Award from the U.S. Centers for Disease Control and Prevention for achieving excellence in community water fluoridation by maintaining a consistent level of fluoridated water.