Water Quality/Hardness 

The Cottage Grove Utility Department is continuously maintaining and upgrading the infrastructure required to bring the residents and businesses of the city a safe and abundant supply of water.

Water Quality/Hardness (milligrams per liter or parts per million):

• Chlorine: 0.4 mg/L
• Fluoride: 1.1 mg/L
• Alkalinity: 236 mg/L
• pH: 7.6
• Hardness: 298 mg/L (17 grains per gallon)

Consumer Confidence Water Quality Reports

• Read the 2023 Cottage Grove Consumer Confidence Water Quality Report (PDF)
• Read the 2022 Cottage Grove Consumer Confidence Water Quality Report (PDF)
• Read the 2021 Cottage Grove Consumer Confidence Water Quality Report (PDF)
• Read the 2020 Cottage Grove Consumer Confidence Water Quality Report (PDF)