Water Softening

Current status in Woodbury

The hardness of the Woodbury water supply is typically in the range of 250 to 360 mg/L as calcium carbonate (CaCO3) or 13.5 grains, which is considered hard. Water hardness is caused mainly by calcium and magnesium dissolved in the water. These minerals will react with soap and detergents creating a difficult to remove scum. High hardness waters will also cause scaling in water pipes, hot water heaters, and appliances. Higher levels of calcium and magnesium in water lead to higher concentrations of dissolved solids.  

While water softening is not necessary, many residents currently choose to add water softeners to their homes. To remove the hardness, water softening is primarily achieved in one of two ways; ion exchange softeners, which are primarily found in residential homes, or centralized lime/soda ash softening, which takes place in water treatment plants prior to distribution. 

Future Softening Potential

The city is constructing a new permanent Woodbury Water Treatment Plant to provide drinking water for the residents and industries of Woodbury. The centralized water treatment plant will treat for per- and polyfluoroalkyl substances (PFAS) which is the primary contaminant of concern. As part of the permanent Woodbury Woodbury Water Treatment Plant, the city is also interested in evaluating other treatment goals that may be of benefit to the residents. One possible treatment goal is softening. Adding centralized lime/soda ash softening would soften water to a level of 125 mg/L or less, reducing the need for residents to use ion exchange water softeners in their homes. This would have various positive impacts on residents, our community, and the environment.  

To learn more about the potential environmental, economic, and social benefits of centralized softening, view the Woodbury Water Softening Memo here: