What the service involves, which devices are available, and when installation or testing is required for properties in Hampden Township and surrounding areas.
What backflow prevention addresses
Backflow is the reverse flow of water or other substances into the public drinking water system. It occurs when pressure changes cause water to flow in the opposite direction from its intended path — from a private plumbing system back into the municipal supply.
There are two causes: backpressure, when pressure in a private system exceeds the supply pressure, and backsiphonage, when negative pressure in the main supply creates a vacuum effect.
A backflow preventer installed at the service connection isolates the private system from the public supply, ensuring that water cannot flow backward regardless of pressure changes.
At a glance
Protects
Public water supply
Installed
At service connection or meter
Testing
Required annually in most cases
Device type
Determined by hazard level
Equipment types
Which device your property needs
RPZ
Reduced Pressure Zone Device
An RPZ device provides the highest level of mechanical protection. It contains two independently operating check valves and a hydraulically operated differential relief valve located between them.
Under normal flow, the relief valve remains closed. If either check valve leaks or if pressure conditions change, the relief valve opens and discharges water — preventing contamination from passing through.
Common applications
Lawn irrigation systems
Fire sprinkler systems with additives
Commercial and industrial facilities
DCVA
Double Check Valve Assembly
A DCVA consists of two spring-loaded check valves in series. It protects against both backpressure and backsiphonage in situations where the hazard level is low to moderate.
Unlike an RPZ, a DCVA does not have a relief valve. It is commonly used where contamination would be objectionable but not dangerous to health.
Common applications
Fire sprinkler systems (no additives)
Low-hazard commercial applications
Requirements
When backflow prevention is required
Pennsylvania regulations require backflow prevention at service connections where a cross-connection hazard exists. The specific requirements depend on your water authority and the nature of your property.
Typically required for
Irrigation systems connected to municipal water
Fire sprinkler systems
Commercial and industrial facilities
Properties with auxiliary water systems
About compliance
Your specific requirements are determined by your water authority and the degree of hazard present at your property. If you've received a notice requiring installation or testing, or if you're unsure whether your property requires a device, calling to discuss the situation is the best first step.
Common questions
Service questions
In most cases, yes. Lawn irrigation systems connected to municipal water supplies typically require an approved backflow prevention device — commonly a reduced pressure zone (RPZ) assembly or a pressure vacuum breaker, depending on local requirements. Your water authority can confirm the specific requirement for your property.
Most testable assemblies require annual testing, though the exact schedule is set by your water authority. Some devices require testing at installation and annually thereafter. Your water supplier will notify you when testing is due.
An RPZ provides a higher level of protection and is used for health hazards. It has a relief valve that discharges if the device fails. A double check valve assembly is used for lower-hazard situations where contamination would be objectionable but not dangerous to health. The required device depends on your property's specific hazard level.
Many assemblies can be repaired if they fail testing — components like check valve assemblies, relief valve kits, and seals are often replaceable. Whether repair or replacement is appropriate depends on the specific failure and the condition of the device. This can be assessed during a service visit.
Water authorities can discontinue service for non-compliance. Most suppliers send notification letters before taking enforcement action, but failure to install or test a required device can ultimately result in water service termination.
Discuss your property's requirements
Call to talk through your situation and schedule installation or testing.