Roseville's water supply comes from Folsom Lake and is treated at the Water Treatment Plant on Barton Road. In order to provide reliability in time of water shortage or emergency outages, the City also maintains five groundwater wells and several interties with surrounding water agencies.

The drinking water is considered to be moderately soft. The hardness of the water averages 33 milligrams per liter which is equal to 1.9 grains per gallon. [0-50 Soft; 50-100 moderate; 100-150 moderately hard; 150-200 hard; 200+ very hard]

Fluoride is added to the drinking water at approximately 0.80 milligrams per liter of water for Roseville customers receiving Roseville treated water. There are some areas in Roseville that are serviced by other water providers and do not receive fluoridated water. If you get a water bill from the City of Roseville, your water is fluoridated.