Examples of Backflow Incidents That Can Occur Are:

• Lawn chemicals backflowing (backsiphoning) through a garden hose into indoor plumbing and potentially into the distribution system.
• Backsiphonage of "blue water" from a toilet into a building's water supply.
• Carbonated water from a restaurant's soda dispenser entering a water system due to back pressure.
• Backsiphonage of chemicals from industrial buildings into distribution system mains.
• Backflow of boiler corrosion control chemicals into an office building's water supply.

For more information on cross connection control and backflow prevention please contact:

• Water Department
  Certified Backflow Testers and Cross Connection Surveyors
  Phone: 978-692-5529
• Massachusetts Department of Environmental Protection (DEP)
  Otavio DePaula-Santos contact by phone at 617-556-1085
  Paul Niman contact by phone at 617-556-1166
  For additional information view the Massachusetts DEP website

Chemical Dispensers

Chemical dispensers, commonly used to dispense cleaning agents are frequently connected to the public water system. These devices need backflow protection. View the Guidelines for Public Water Systems (PDF) for Massachusetts DEP requirements for chemical dispenser.