Notification of Treatment Change:

Williams Station Wells Transition from Free Chlorine to Chloramine

Starting July 8, 2024, SJW will transition from using free chlorine to chloramine as the primary disinfectant for the water supplied by our Williams Station Wells. This change is part of our ongoing commitment to providing the highest quality water.

Who will be impacted?

This information is for residents and businesses in the Cox Pressure Zone, where this change will impact approximately 16,000 customers (see map). We are excited about the positive impact this will have on the quality of your water.

Map of impacted service area to treatment change
Why the Change?

The shift to chloramine is a proven and trusted method within our service area. Mountain surface water produced by SJW's Montevina Water Treatment Plant, as well as surface water purchased from Valley Water, already utilize chloramines. The benefits of this change include:

  • Improved Water Quality: Reducing the blending of chlorine and chloramines on zone boundaries enhances the overall water quality in our distribution system.
  • Reduced Disinfection Byproducts (DBPs): Chloramines produce lower levels of disinfection byproducts compared to free chlorine, resulting in safer, cleaner water.
  • Effective Protection: Chloramines are highly effective in protecting against waterborne diseases, ensuring the water you receive is safe for all your needs.
Safety and Usage

Water treated with chloramines is safe for drinking, bathing, cooking, and most other household uses. However, there are specific groups who need to take special precautions:

  • Kidney Dialysis Patients: The change to chloramines can cause problems for individuals dependent on dialysis machines. Hemolytic anemia can occur if chloramines are not completely removed from the water used in dialysis. The pretreatment scheme for dialysis units must include a method, such as a charcoal filter, for removing chloramines. Medical facilities should also review whether additional precautions are necessary for other medical equipment.
  • Live Fish or Other Aquatic Animal Owners: Chloraminated water may be toxic to fish and other aquatic animals. If you maintain a fish tank or aquarium, ensure that the chemicals or filters you use are suitable for water treated with chloramines. You may need to change your filtration system to accommodate this change.

If you have any questions or need further information, please contact our Customer Service team at (408) 279-7900 or customer.service@sjwater.com. For more information about San Jose Water’s drinking water quality, view our Annual Water Quality Report at sjwater.com/ccr.