The Village of Holmen Board approved an ordinance that defines why and how the city fluoridates their water Thursday night, according to Village Administrator Scott Heinig.

Fluoridation is now required by law in the Village of Holmen,” he wrote in an email to News 19.

Since June, the village has treated water with fluoride.

Holmen’s plan dates back to 2008, after residents voted on a binding referendum.

But those plans were placed on hold until the U.S. Department of Health and Human Services completed a study on recommended fluoride levels.