Sodium Hypochlorite (Bleach)

This is added to Chicopee’s drinking water for disinfection. It is important to note that disinfection is the elimination of pathogenic disease causing organisms only, where sterilization is the complete elimination of all living organisms. Chlorine levels in the treatment plant finish water are approximately 1.0 to 1.4 mg/L free chlorine.

Less chlorine is needed during the colder months of the year to maintain a residual at the further extremities of the system. Our year-round target is 0.2 mg/L free chlorine at the furthest points in the system. Usage ranges from 15 to 25 gallons of sodium hypochlorite per day, depending primarily on water temperature and usage.

Chicopee’s water also receives disinfection with Sodium Hypochlorite (bleach) at the Ware Disinfection Facility in Ware, Massachusetts before it reaches Chicopee. The dose leaving the facility has ranged from 1.2 to 1.6 mg/L over the past few years. This water flows through the Chicopee Valley Aqueduct (CVA) to Chicopee, Wilbraham, and Fire District 1 of South Hadley. When the water reaches Chicopee, the chlorine residual is approximately 0.5 to 0.6 mg/L free chlorine before it is increased to a level that will assure disinfection of the City's distribution system.